[Code of Federal Regulations]
[Title 29, Volume 8]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 29CFR1926.62]
[Page 81-112]
TITLE 29--LABOR
CHAPTER XVII--OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT
OF LABOR
PART 1926_SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION--Table of Contents
Subpart D_Occupational Health and Environmental Controls
Sec. 1926.62 Lead.
(a) Scope. This section applies to all construction work where an
employee may be occupationally exposed to lead. All construction work
excluded from coverage in the general industry standard for lead by 29
CFR 1910.1025(a)(2) is covered by this standard. Construction work is
defined as work for construction, alteration and/or repair, including
painting and decorating. It includes but is not limited to the
following:
(1) Demolition or salvage of structures where lead or materials
containing lead are present;
(2) Removal or encapsulation of materials containing lead;
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(3) New construction, alteration, repair, or renovation of
structures, substrates, or portions thereof, that contain lead, or
materials containing lead;
(4) Installation of products containing lead;
(5) Lead contamination/emergency cleanup;
(6) Transportation, disposal, storage, or containment of lead or
materials containing lead on the site or location at which construction
activities are performed, and
(7) Maintenance operations associated with the construction
activities described in this paragraph.
(b) Definitions.
Action level means employee exposure, without regard to the use of
respirators, to an airborne concentration of lead of 30 micrograms per
cubic meter of air (30 [micro]g/m\3\) calculated as an 8-hour time-
weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Competent person means one who is capable of identifying existing
and predictable lead hazards in the surroundings or working conditions
and who has authorization to take prompt corrective measures to
eliminate them.
Director means the Director, National Institute for Occupational
Safety and Health (NIOSH), U.S. Department of Health and Human Services,
or designee.
Lead means metallic lead, all inorganic lead compounds, and organic
lead soaps. Excluded from this definition are all other organic lead
compounds.
This section means this standard.
(c) Permissible exposure limit. (1) The employer shall assure that
no employee is exposed to lead at concentrations greater than fifty
micrograms per cubic meter of air (50 [micro]g/m\3\) averaged over an 8-
hour period.
(2) If an employee is exposed to lead for more than 8 hours in any
work day the employees' allowable exposure, as a time weighted average
(TWA) for that day, shall be reduced according to the following formula:
Allowable employee exposure (in [micro]g/m\3\) = 400 divided by hours
worked in the day.
(3) When respirators are used to limit employee exposure as required
under paragraph (c) of this section and all the requirements of
paragraphs (e)(1) and (f) of this section have been met, employee
exposure may be considered to be at the level provided by the protection
factor of the respirator for those periods the respirator is worn. Those
periods may be averaged with exposure levels during periods when
respirators are not worn to determine the employee's daily TWA exposure.
(d) Exposure assessment--(1) General. (i) Each employer who has a
workplace or operation covered by this standard shall initially
determine if any employee may be exposed to lead at or above the action
level.
(ii) For the purposes of paragraph (d) of this section, employee
exposure is that exposure which would occur if the employee were not
using a respirator.
(iii) With the exception of monitoring under paragraph (d)(3), where
monitoring is required under this section, the employer shall collect
personal samples representative of a full shift including at least one
sample for each job classification in each work area either for each
shift or for the shift with the highest exposure level.
(iv) Full shift personal samples shall be representative of the
monitored employee's regular, daily exposure to lead.
(2) Protection of employees during assessment of exposure. (i) With
respect to the lead related tasks listed in paragraph (d)(2)(i) of this
section, where lead is present, until the employer performs an employee
exposure assessment as required in paragraph (d) of this section and
documents that the employee performing any of the listed tasks is not
exposed above the PEL, the employer shall treat the employee as if the
employee were exposed above the PEL, and not in excess of ten (10) times
the PEL, and shall implement employee protective measures prescribed in
paragraph (d)(2)(v) of this section. The tasks covered by this
requirement are:
(A) Where lead containing coatings or paint are present: Manual
demolition of structures (e.g, dry wall), manual scraping, manual
sanding, heat gun
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applications, and power tool cleaning with dust collection systems;
(B) Spray painting with lead paint.
(ii) In addition, with regard to tasks not listed in paragraph
(d)(2)(i), where the employee has any reason to believe that an employee
performing the task may be exposed to lead in excess of the PEL, until
the employer performs an employee exposure assessment as required by
paragraph (d) of this section and documents that the employee's lead
exposure is not above the PEL the employer shall treat the employee as
if the employee were exposed above the PEL and shall implememt employee
protective measures as prescribed in paragraph (d)(2)(v) of this
section.
(iii) With respect to the tasks listed in paragraph (d)(2)(iii) of
this section, where lead is present, until the employer performs an
employee exposure assessment as required in paragraph (d) of this
section, and documents that the employee performing any of the listed
tasks is not exposed in excess of 500 [micro]g/m\3\, the employer shall
treat the employee as if the employee were exposed to lead in excess of
500 [micro]g/m\3\ and shall implement employee protective measures as
prescribed in paragraph (d)(2)(v) of this section. Where the employer
does establish that the employee is exposed to levels of lead below 500
[micro]g/m\3\, the employer may provide the exposed employee with the
appropriate respirator prescribed for such use at such lower exposures,
in accordance with Table 1 of this section. The tasks covered by this
requirement are:
(A) Using lead containing mortar; lead burning
(B) Where lead containing coatings or paint are present: rivet
busting; power tool cleaning without dust collection systems; cleanup
activities where dry expendable abrasives are used; and abrasive
blasting enclosure movement and removal.
(iv) With respect to the tasks listed in paragraph (d)(2)(iv) of
this section, where lead is present, until the employer performs an
employee exposure assessment as required in paragraph (d) of this
section and documents that the employee performing any of the listed
tasks is not exposed to lead in excess of 2,500 [micro]g/m\3\ (50xPEL),
the employer shall treat the employee as if the employee were exposed to
lead in excess of 2,500 [micro]g/m\3\ and shall implement employee
protective measures as prescribed in paragraph (d)(2)(v) of this
section. Where the employer does establish that the employee is exposed
to levels of lead below 2,500 [micro]g/m3, the employer may provide the
exposed employee with the appropriate respirator prescribed for use at
such lower exposures, in accordance with Table I of this section.
Interim protection as described in this paragaraph is required where
lead containing coatings or paint are present on structures when
performing:
(A) Abrasive blasting,
(B) Welding,
(C) Cutting, and
(D) Torch burning.
(v) Until the employer performs an employee exposure assessment as
required under paragraph (d) of this section and determines actual
employee exposure, the employer shall provide to employees performing
the tasks described in paragraphs (d)(2)(i), (d)(2)(ii), (d)(2)(iii),
and (d)(2)(iv) of this section with interim protection as follows:
(A) Appropriate respiratory protection in accordance with paragraph
(f) of this section.
(B) Appropriate personal protective clothing and equipment in
accordance with paragraph (g) of this section.
(C) Change areas in accordance with paragraph (i)(2) of this
section.
(D) Hand washing facilities in accordance with paragraph (i)(5) of
this section.
(E) Biological monitoring in accordance with paragraph (j)(1)(i) of
this section, to consist of blood sampling and analysis for lead and
zinc protoporphyrin levels, and
(F) Training as required under paragraph (l)(1)(i) of this section
regarding 29 CFR 1926.59, Hazard Communication; training as required
under paragraph (1)(2)(iii) of this section, regarding use of
respirators; and training in accordance with 29 CFR 1926.21, Safety
training and education.
(3) Basis of initial determination. (i) Except as provided under
paragraphs (d)(3)(iii) and (d)(3)(iv) of this section the employer shall
monitor employee exposures and shall base initial determinations on the
employee exposure
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monitoring results and any of the following, relevant considerations:
(A) Any information, observations, or calculations which would
indicate employee exposure to lead;
(B) Any previous measurements of airborne lead; and
(C) Any employee complaints of symptoms which may be attributable to
exposure to lead.
(ii) Monitoring for the initial determination where performed may be
limited to a representative sample of the exposed employees who the
employer reasonably believes are exposed to the greatest airborne
concentrations of lead in the workplace.
(iii) Where the employer has previously monitored for lead
exposures, and the data were obtained within the past 12 months during
work operations conducted under workplace conditions closely resembling
the processes, type of material, control methods, work practices, and
environmental conditions used and prevailing in the employer's current
operations, the employer may rely on such earlier monitoring results to
satisfy the requirements of paragraphs (d)(3)(i) and (d)(6) of this
section if the sampling and analytical methods meet the accuracy and
confidence levels of paragraph (d)(10) of this section.
(iv) Where the employer has objective data, demonstrating that a
particular product or material containing lead or a specific process,
operation or activity involving lead cannot result in employee exposure
to lead at or above the action level during processing, use, or
handling, the employer may rely upon such data instead of implementing
initial monitoring.
(A) The employer shall establish and maintain an accurate record
documenting the nature and relevancy of objective data as specified in
paragraph (n)(4) of this section, where used in assessing employee
exposure in lieu of exposure monitoring.
(B) Objective data, as described in paragraph (d)(3)(iv) of this
section, is not permitted to be used for exposure assessment in
connection with paragraph (d)(2) of this section.
(4) Positive initial determination and initial monitoring. (i) Where
a determination conducted under paragraphs (d) (1), (2) and (3) of this
section shows the possibility of any employee exposure at or above the
action level the employer shall conduct monitoring which is
representative of the exposure for each employee in the workplace who is
exposed to lead.
(ii) Where the employer has previously monitored for lead exposure,
and the data were obtained within the past 12 months during work
operations conducted under workplace conditions closely resembling the
processes, type of material, control methods, work practices, and
environmental conditions used and prevailing in the employer's current
operations, the employer may rely on such earlier monitoring results to
satisfy the requirements of paragraph (d)(4)(i) of this section if the
sampling and analytical methods meet the accuracy and confidence levels
of paragraph (d)(10) of this section.
(5) Negative initial determination. Where a determination, conducted
under paragraphs (d) (1), (2), and (3) of this section is made that no
employee is exposed to airborne concentrations of lead at or above the
action level the employer shall make a written record of such
determination. The record shall include at least the information
specified in paragraph (d)(3)(i) of this section and shall also include
the date of determination, location within the worksite, and the name
and social security number of each employee monitored.
(6) Frequency. (i) If the initial determination reveals employee
exposure to be below the action level further exposure determination
need not be repeated except as otherwise provided in paragraph (d)(7) of
this section.
(ii) If the initial determination or subsequent determination
reveals employee exposure to be at or above the action level but at or
below the PEL the employer shall perform monitoring in accordance with
this paragraph at least every 6 months. The employer shall continue
monitoring at the required frequency until at least two consecutive
measurements, taken at least 7 days apart, are below the action level at
which time the employer may
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discontinue monitoring for that employee except as otherwise provided in
paragraph (d)(7) of this section.
(iii) If the initial determination reveals that employee exposure is
above the PEL the employer shall perform monitoring quarterly. The
employer shall continue monitoring at the required frequency until at
least two consecutive measurements, taken at least 7 days apart, are at
or below the PEL but at or above the action level at which time the
employer shall repeat monitoring for that employee at the frequency
specified in paragraph (d)(6)(ii) of this section, except as otherwise
provided in paragraph (d)(7) of this section. The employer shall
continue monitoring at the required frequency until at least two
consecutive measurements, taken at least 7 days apart, are below the
action level at which time the employer may discontinue monitoring for
that employee except as otherwise provided in paragraph (d)(7) of this
section.
(7) Additional exposure assessments. Whenever there has been a
change of equipment, process, control, personnel or a new task has been
initiated that may result in additional employees being exposed to lead
at or above the action level or may result in employees already exposed
at or above the action level being exposed above the PEL, the employer
shall conduct additional monitoring in accordance with this paragraph.
(8) Employee notification. (i) The employer must, as soon as
possible but no later than 5 working days after the receipt of the
results of any monitoring performed under this section, notify each
affected employee of these results either individually in writing or by
posting the results in an appropriate location that is accessible to
employees.
(ii) Whenever the results indicate that the representative employee
exposure, without regard to respirators, is at or above the PEL the
employer shall include in the written notice a statement that the
employees exposure was at or above that level and a description of the
corrective action taken or to be taken to reduce exposure to below that
level.
(9) Accuracy of measurement. The employer shall use a method of
monitoring and analysis which has an accuracy (to a confidence level of
95%) of not less than plus or minus 25 percent for airborne
concentrations of lead equal to or greater than 30 [micro]g/m\3\.
(e) Methods of compliance--(1) Engineering and work practice
controls. The employer shall implement engineering and work practice
controls, including administrative controls, to reduce and maintain
employee exposure to lead to or below the permissible exposure limit to
the extent that such controls are feasible. Wherever all feasible
engineering and work practices controls that can be instituted are not
sufficient to reduce employee exposure to or below the permissible
exposure limit prescribed in paragraph (c) of this section, the employer
shall nonetheless use them to reduce employee exposure to the lowest
feasible level and shall supplement them by the use of respiratory
protection that complies with the requirements of paragraph (f) of this
section.
(2) Compliance program. (i) Prior to commencement of the job each
employer shall establish and implement a written compliance program to
achieve compliance with paragraph (c) of this section.
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each activity in which lead is emitted; e.g.
equipment used, material involved, controls in place, crew size,
employee job responsibilities, operating procedures and maintenance
practices;
(B) A description of the specific means that will be employed to
achieve compliance and, where engineering controls are required
engineering plans and studies used to determine methods selected for
controlling exposure to lead;
(C) A report of the technology considered in meeting the PEL;
(D) Air monitoring data which documents the source of lead
emissions;
(E) A detailed schedule for implementation of the program, including
documentation such as copies of purchase orders for equipment,
construction contracts, etc.;
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(F) A work practice program which includes items required under
paragraphs (g), (h) and (i) of this section and incorporates other
relevant work practices such as those specified in paragraph (e)(5) of
this section;
(G) An administrative control schedule required by paragraph (e)(4)
of this section, if applicable;
(H) A description of arrangements made among contractors on multi-
contractor sites with respect to informing affected employees of
potential exposure to lead and with respect to responsibility for
compliance with this section as set-forth in Sec. 1926.16.
(I) Other relevant information.
(iii) The compliance program shall provide for frequent and regular
inspections of job sites, materials, and equipment to be made by a
competent person.
(iv) Written programs shall be submitted upon request to any
affected employee or authorized employee representatives, to the
Assistant Secretary and the Director, and shall be available at the
worksite for examination and copying by the Assistant Secretary and the
Director.
(v) Written programs must be revised and updated at least annually
to reflect the current status of the program.
(3) Mechanical ventilation. When ventilation is used to control lead
exposure, the employer shall evaluate the mechanical performance of the
system in controlling exposure as necessary to maintain its
effectiveness.
(4) Administrative controls. If administrative controls are used as
a means of reducing employees TWA exposure to lead, the employer shall
establish and implement a job rotation schedule which includes:
(i) Name or identification number of each affected employee;
(ii) Duration and exposure levels at each job or work station where
each affected employee is located; and
(iii) Any other information which may be useful in assessing the
reliability of administrative controls to reduce exposure to lead.
(5) The employer shall ensure that, to the extent relevant,
employees follow good work practices such as described in Appendix B of
this section.
(f) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide
respirators that comply with the requirements of this paragraph.
Respirators must be used during:
(i) Periods when an employee's exposure to lead exceeds the PEL.
(ii) Work operations for which engineering and work-practice
controls are not sufficient to reduce employee exposures to or below the
PEL.
(iii) Periods when an employee requests a respirator.
(iv) Periods when respirators are required to provide interim
protection of employees while they perform the operations specified in
paragraph (d)(2) of this section.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance with 29 CFR 1910.134 (b)
through (d) (except (d)(1)(iii)), and (f) through (m).
(ii) If an employee has breathing difficulty during fit testing or
respirator use, the employer must provide the employee with a medical
examination in accordance with paragraph (j)(3)(i)(B) of this section to
determine whether or not the employee can use a respirator while
performing the required duty.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide employees with a full facepiece respirator instead of a
half mask respirator for protection against lead aerosols that may cause
eye or skin irritation at the use concentrations.
(C) Provide HEPA filters for powered and non-powered air-purifying
respirators.
(ii) The employer must provide a powered air-purifying respirator
when an employee chooses to use such a respirator and it will provide
adequate protection to the employee.
(g) Protective work clothing and equipment--(1) Provision and use.
Where an employee is exposed to lead above the PEL without regard to the
use of respirators, where employees are exposed to lead compounds which
may cause
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skin or eye irritation (e.g. lead arsenate, lead azide), and as interim
protection for employees performing tasks as specified in paragraph
(d)(2) of this section, the employer shall provide at no cost to the
employee and assure that the employee uses appropriate protective work
clothing and equipment that prevents contamination of the employee and
the employee's garments such as, but not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, hats, and shoes or disposable shoe coverlets; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment which complies with Sec. 1910.133 of this chapter.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required in paragraph (g)(1) of this section in a
clean and dry condition at least weekly, and daily to employees whose
exposure levels without regard to a respirator are over 200 [micro]g/
m\3\ of lead as an 8-hour TWA.
(ii) The employer shall provide for the cleaning, laundering, and
disposal of protective clothing and equipment required by paragraph
(g)(1) of this section.
(iii) The employer shall repair or replace required protective
clothing and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change areas provided
for that purpose as prescribed in paragraph (i)(2) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a closed
container in the change area which prevents dispersion of lead outside
the container.
(vi) The employer shall inform in writing any person who cleans or
launders protective clothing or equipment of the potentially harmful
effects of exposure to lead.
(vii) The employer shall assure that the containers of contaminated
protective clothing and equipment required by paragraph (g)(2)(v) of
this section are labeled as follows:
Caution: Clothing contaminated with lead. Do not remove dust by blowing
or shaking. Dispose of lead contaminated wash water in accordance with
applicable local, state, or federal regulations.
(viii) The employer shall prohibit the removal of lead from
protective clothing or equipment by blowing, shaking, or any other means
which disperses lead into the air.
(h) Housekeeping--(1) All surfaces shall be maintained as free as
practicable of accumulations of lead.
(2) Clean-up of floors and other surfaces where lead accumulates
shall wherever possible, be cleaned by vacuuming or other methods that
minimize the likelihood of lead becoming airborne.
(3) Shoveling, dry or wet sweeping, and brushing may be used only
where vacuuming or other equally effective methods have been tried and
found not to be effective.
(4) Where vacuuming methods are selected, the vacuums shall be
equipped with HEPA filters and used and emptied in a manner which
minimizes the reentry of lead into the workplace.
(5) Compressed air shall not be used to remove lead from any surface
unless the compressed air is used in conjunction with a ventilation
system designed to capture the airborne dust created by the compressed
air.
(i) Hygiene facilities and practices. (1) The employer shall assure
that in areas where employees are exposed to lead above the PEL without
regard to the use of respirators, food or beverage is not present or
consumed, tobacco products are not present or used, and cosmetics are
not applied.
(2) Change areas. (i) The employer shall provide clean change areas
for employees whose airborne exposure to lead is above the PEL, and as
interim protection for employees performing tasks as specified in
paragraph (d)(2) of this section, without regard to the use of
respirators.
(ii) The employer shall assure that change areas are equipped with
separate storage facilities for protective work clothing and equipment
and for street clothes which prevent cross-contamination.
(iii) The employer shall assure that employees do not leave the
workplace
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wearing any protective clothing or equipment that is required to be worn
during the work shift.
(3) Showers. (i) The employer shall provide shower facilities, where
feasible, for use by employees whose airborne exposure to lead is above
the PEL.
(ii) The employer shall assure, where shower facilities are
available, that employees shower at the end of the work shift and shall
provide an adequate supply of cleansing agents and towels for use by
affected employees.
(4) Eating facilities. (i) The employer shall provide lunchroom
facilities or eating areas for employees whose airborne exposure to lead
is above the PEL, without regard to the use of respirators.
(ii) The employer shall assure that lunchroom facilities or eating
areas are as free as practicable from lead contamination and are readily
accessible to employees.
(iii) The employer shall assure that employees whose airborne
exposure to lead is above the PEL, without regard to the use of a
respirator, wash their hands and face prior to eating, drinking, smoking
or applying cosmetics.
(iv) The employer shall assure that employees do not enter lunchroom
facilities or eating areas with protective work clothing or equipment
unless surface lead dust has been removed by vacuuming, downdraft booth,
or other cleaning method that limits dispersion of lead dust.
(5) Hand washing facilities. (i) The employer shall provide adequate
handwashing facilities for use by employees exposed to lead in
accordance with 29 CFR 1926.51(f).
(ii) Where showers are not provided the employer shall assure that
employees wash their hands and face at the end of the work-shift.
(j) Medical surveillance--(1) General. (i) The employer shall make
available initial medical surveillance to employees occupationally
exposed on any day to lead at or above the action level. Initial medical
surveillance consists of biological monitoring in the form of blood
sampling and analysis for lead and zinc protoporphyrin levels.
(ii) The employer shall institute a medical surveillance program in
accordance with paragraphs (j)(2) and (j)(3) of this section for all
employees who are or may be exposed by the employer at or above the
action level for more than 30 days in any consecutive 12 months;
(iii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician.
(iv) The employer shall make available the required medical
surveillance including multiple physician review under paragraph
(j)(3)(iii) without cost to employees and at a reasonable time and
place.
(2) Biological monitoring--(i) Blood lead and ZPP level sampling and
analysis. The employer shall make available biological monitoring in the
form of blood sampling and analysis for lead and zinc protoporphyrin
levels to each employee covered under paragraphs (j)(1)(i) and (ii) of
this section on the following schedule:
(A) For each employee covered under paragraph (j)(1)(ii) of this
section, at least every 2 months for the first 6 months and every 6
months thereafter;
(B) For each employee covered under paragraphs (j)(1) (i) or (ii) of
this section whose last blood sampling and analysis indicated a blood
lead level at or above 40 [micro]g/dl, at least every two months. This
frequency shall continue until two consecutive blood samples and
analyses indicate a blood lead level below 40 [micro]g/dl; and
(C) For each employee who is removed from exposure to lead due to an
elevated blood lead level at least monthly during the removal period.
(ii) Follow-up blood sampling tests. Whenever the results of a blood
lead level test indicate that an employee's blood lead level exceeds the
numerical criterion for medical removal under paragraph (k)(1)(i) of
this section, the employer shall provide a second (follow-up) blood
sampling test within two weeks after the employer receives the results
of the first blood sampling test.
(iii) Accuracy of blood lead level sampling and analysis. Blood lead
level sampling and analysis provided pursuant to this section shall have
an accuracy (to a confidence level of 95 percent) within plus or minus
15 percent or 6 [micro]g/dl, whichever is greater, and
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shall be conducted by a laboratory approved by OSHA.
(iv) Employee notification. (A) Within five working days after the
receipt of biological monitoring results, the employer shall notify each
employee in writing of his or her blood lead level; and
(B) The employer shall notify each employee whose blood lead level
exceeds 40 [micro]g/dl that the standard requires temporary medical
removal with Medical Removal Protection benefits when an employee's
blood lead level exceeds the numerical criterion for medical removal
under paragraph (k)(1)(i) of this section.
(3) Medical examinations and consultations--(i) Frequency. The
employer shall make available medical examinations and consultations to
each employee covered under paragraph (j)(1)(ii) of this section on the
following schedule:
(A) At least annually for each employee for whom a blood sampling
test conducted at any time during the preceding 12 months indicated a
blood lead level at or above 40 [micro]g/dl;
(B) As soon as possible, upon notification by an employee either
that the employee has developed signs or symptoms commonly associated
with lead intoxication, that the employee desires medical advice
concerning the effects of current or past exposure to lead on the
employee's ability to procreate a healthy child, that the employee is
pregnant, or that the employee has demonstrated difficulty in breathing
during a respirator fitting test or during use; and
(C) As medically appropriate for each employee either removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited pursuant to a final medical determination.
(ii) Content. The content of medical examinations made available
pursuant to paragraph (j)(3)(i)(B)-(C) of this section shall be
determined by an examining physician and, if requested by an employee,
shall include pregnancy testing or laboratory evaluation of male
fertility. Medical examinations made available pursuant to paragraph
(j)(3)(i)(A) of this section shall include the following elements:
(A) A detailed work history and a medical history, with particular
attention to past lead exposure (occupational and non-occupational),
personal habits (smoking, hygiene), and past gastrointestinal,
hematologic, renal, cardiovascular, reproductive and neurological
problems;
(B) A thorough physical examination, with particular attention to
teeth, gums, hematologic, gastrointestinal, renal, cardiovascular, and
neurological systems. Pulmonary status should be evaluated if
respiratory protection will be used;
(C) A blood pressure measurement;
(D) A blood sample and analysis which determines:
(1) Blood lead level;
(2) Hemoglobin and hematocrit determinations, red cell indices, and
examination of peripheral smear morphology;
(3) Zinc protoporphyrin;
(4) Blood urea nitrogen; and,
(5) Serum creatinine;
(E) A routine urinalysis with microscopic examination; and
(F) Any laboratory or other test relevant to lead exposure which the
examining physician deems necessary by sound medical practice.
(iii) Multiple physician review mechanism. (A) If the employer
selects the initial physician who conducts any medical examination or
consultation provided to an employee under this section, the employee
may designate a second physician:
(1) To review any findings, determinations or recommendations of the
initial physician; and
(2) To conduct such examinations, consultations, and laboratory
tests as the second physician deems necessary to facilitate this review.
(B) The employer shall promptly notify an employee of the right to
seek a second medical opinion after each occasion that an initial
physician conducts a medical examination or consultation pursuant to
this section. The employer may condition its participation in, and
payment for, the multiple physician review mechanism upon the employee
doing the following within fifteen (15) days after receipt of the
foregoing notification, or receipt of the
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initial physician's written opinion, whichever is later:
(1) The employee informing the employer that he or she intends to
seek a second medical opinion, and
(2) The employee initiating steps to make an appointment with a
second physician.
(C) If the findings, determinations or recommendations of the second
physician differ from those of the initial physician, then the employer
and the employee shall assure that efforts are made for the two
physicians to resolve any disagreement.
(D) If the two physicians have been unable to quickly resolve their
disagreement, then the employer and the employee through their
respective physicians shall designate a third physician:
(1) To review any findings, determinations or recommendations of the
prior physicians; and
(2) To conduct such examinations, consultations, laboratory tests
and discussions with the prior physicians as the third physician deems
necessary to resolve the disagreement of the prior physicians.
(E) The employer shall act consistent with the findings,
determinations and recommendations of the third physician, unless the
employer and the employee reach an agreement which is otherwise
consistent with the recommendations of at least one of the three
physicians.
(iv) Information provided to examining and consulting physicians.
(A) The employer shall provide an initial physician conducting a medical
examination or consultation under this section with the following
information:
(1) A copy of this regulation for lead including all Appendices;
(2) A description of the affected employee's duties as they relate
to the employee's exposure;
(3) The employee's exposure level or anticipated exposure level to
lead and to any other toxic substance (if applicable);
(4) A description of any personal protective equipment used or to be
used;
(5) Prior blood lead determinations; and
(6) All prior written medical opinions concerning the employee in
the employer's possession or control.
(B) The employer shall provide the foregoing information to a second
or third physician conducting a medical examination or consultation
under this section upon request either by the second or third physician,
or by the employee.
(v) Written medical opinions. (A) The employer shall obtain and
furnish the employee with a copy of a written medical opinion from each
examining or consulting physician which contains only the following
information:
(1) The physician's opinion as to whether the employee has any
detected medical condition which would place the employee at increased
risk of material impairment of the employee's health from exposure to
lead;
(2) Any recommended special protective measures to be provided to
the employee, or limitations to be placed upon the employee's exposure
to lead;
(3) Any recommended limitation upon the employee's use of
respirators, including a determination of whether the employee can wear
a powered air purifying respirator if a physician determines that the
employee cannot wear a negative pressure respirator; and
(4) The results of the blood lead determinations.
(B) The employer shall instruct each examining and consulting
physician to:
(1) Not reveal either in the written opinion or orally, or in any
other means of communication with the employer, findings, including
laboratory results, or diagnoses unrelated to an employee's occupational
exposure to lead; and
(2) Advise the employee of any medical condition, occupational or
nonoccupational, which dictates further medical examination or
treatment.
(vi) Alternate physician determination mechanisms. The employer and
an employee or authorized employee representative may agree upon the use
of any alternate physician determination mechanism in lieu of the
multiple physician review mechanism provided by paragraph (j)(3)(iii) of
this section so long as the alternate mechanism is as
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expeditious and protective as the requirements contained in this
paragraph.
(4) Chelation. (i) The employer shall assure that any person whom he
retains, employs, supervises or controls does not engage in prophylactic
chelation of any employee at any time.
(ii) If therapeutic or diagnostic chelation is to be performed by
any person in paragraph (j)(4)(i) of this section, the employer shall
assure that it be done under the supervision of a licensed physician in
a clinical setting with thorough and appropriate medical monitoring and
that the employee is notified in writing prior to its occurrence.
(k) Medical removal protection--(1) Temporary medical removal and
return of an employee--(i) Temporary removal due to elevated blood lead
level. The employer shall remove an employee from work having an
exposure to lead at or above the action level on each occasion that a
periodic and a follow-up blood sampling test conducted pursuant to this
section indicate that the employee's blood lead level is at or above 50
[micro]g/dl; and,
(ii) Temporary removal due to a final medical determination. (A) The
employer shall remove an employee from work having an exposure to lead
at or above the action level on each occasion that a final medical
determination results in a medical finding, determination, or opinion
that the employee has a detected medical condition which places the
employee at increased risk of material impairment to health from
exposure to lead.
(B) For the purposes of this section, the phrase final medical
determination means the written medical opinion on the employees' health
status by the examining physician or, where relevant, the outcome of the
multiple physician review mechanism or alternate medical determination
mechanism used pursuant to the medical surveillance provisions of this
section.
(C) Where a final medical determination results in any recommended
special protective measures for an employee, or limitations on an
employee's exposure to lead, the employer shall implement and act
consistent with the recommendation.
(iii) Return of the employee to former job status. (A) The employer
shall return an employee to his or her former job status:
(1) For an employee removed due to a blood lead level at or above 50
[micro]g/dl when two consecutive blood sampling tests indicate that the
employee's blood lead level is at or below 40 [micro]g/dl;
(2) For an employee removed due to a final medical determination,
when a subsequent final medical determination results in a medical
finding, determination, or opinion that the employee no longer has a
detected medical condition which places the employee at increased risk
of material impairment to health from exposure to lead.
(B) For the purposes of this section, the requirement that an
employer return an employee to his or her former job status is not
intended to expand upon or restrict any rights an employee has or would
have had, absent temporary medical removal, to a specific job
classification or position under the terms of a collective bargaining
agreement.
(iv) Removal of other employee special protective measure or
limitations. The employer shall remove any limitations placed on an
employee or end any special protective measures provided to an employee
pursuant to a final medical determination when a subsequent final
medical determination indicates that the limitations or special
protective measures are no longer necessary.
(v) Employer options pending a final medical determination. Where
the multiple physician review mechanism, or alternate medical
determination mechanism used pursuant to the medical surveillance
provisions of this section, has not yet resulted in a final medical
determination with respect to an employee, the employer shall act as
follows:
(A) Removal. The employer may remove the employee from exposure to
lead, provide special protective measures to the employee, or place
limitations upon the employee, consistent with the medical findings,
determinations, or recommendations of any of the physicians who have
reviewed the employee's health status.
(B) Return. The employer may return the employee to his or her
former job
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status, end any special protective measures provided to the employee,
and remove any limitations placed upon the employee, consistent with the
medical findings, determinations, or recommendations of any of the
physicians who have reviewed the employee's health status, with two
exceptions.
(1) If the initial removal, special protection, or limitation of the
employee resulted from a final medical determination which differed from
the findings, determinations, or recommendations of the initial
physician or;
(2) If the employee has been on removal status for the preceding
eighteen months due to an elevated blood lead level, then the employer
shall await a final medical determination.
(2) Medical removal protection benefits--(i) Provision of medical
removal protection benefits. The employer shall provide an employee up
to eighteen (18) months of medical removal protection benefits on each
occasion that an employee is removed from exposure to lead or otherwise
limited pursuant to this section.
(ii) Definition of medical removal protection benefits. For the
purposes of this section, the requirement that an employer provide
medical removal protection benefits means that, as long as the job the
employee was removed from continues, the employer shall maintain the
total normal earnings, seniority and other employment rights and
benefits of an employee, including the employee's right to his or her
former job status as though the employee had not been medically removed
from the employee's job or otherwise medically limited.
(iii) Follow-up medical surveillance during the period of employee
removal or limitation. During the period of time that an employee is
medically removed from his or her job or otherwise medically limited,
the employer may condition the provision of medical removal protection
benefits upon the employee's participation in follow-up medical
surveillance made available pursuant to this section.
(iv) Workers' compensation claims. If a removed employee files a
claim for workers' compensation payments for a lead-related disability,
then the employer shall continue to provide medical removal protection
benefits pending disposition of the claim. To the extent that an award
is made to the employee for earnings lost during the period of removal,
the employer's medical removal protection obligation shall be reduced by
such amount. The employer shall receive no credit for workers'
compensation payments received by the employee for treatment- related
expenses.
(v) Other credits. The employer's obligation to provide medical
removal protection benefits to a removed employee shall be reduced to
the extent that the employee receives compensation for earnings lost
during the period of removal either from a publicly or employer-funded
compensation program, or receives income from employment with another
employer made possible by virtue of the employee's removal.
(vi) Voluntary removal or restriction of an employee. Where an
employer, although not required by this section to do so, removes an
employee from exposure to lead or otherwise places limitations on an
employee due to the effects of lead exposure on the employee's medical
condition, the employer shall provide medical removal protection
benefits to the employee equal to that required by paragraph (k)(2) (i)
and (ii) of this section.
(l) Employee information and training--(1) General. (i) The employer
shall communicate information concerning lead hazards according to the
requirements of OSHA's Hazard Communication Standard for the
construction industry, 29 CFR 1926.59, including but not limited to the
requirements concerning warning signs and labels, material safety data
sheets (MSDS), and employee information and training. In addition,
employers shall comply with the following requirements:
(ii) For all employees who are subject to exposure to lead at or
above the action level on any day or who are subject to exposure to lead
compounds which may cause skin or eye irritation (e.g. lead arsenate,
lead azide), the employer shall provide a training program in accordance
with paragraph (l)(2) of this section and assure employee participation.
(iii) The employer shall provide the training program as initial
training
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prior to the time of job assignment or prior to the start up date for
this requirement, whichever comes last.
(iv) The employer shall also provide the training program at least
annually for each employee who is subject to lead exposure at or above
the action level on any day.
(2) Training program. The employer shall assure that each employee
is trained in the following:
(i) The content of this standard and its appendices;
(ii) The specific nature of the operations which could result in
exposure to lead above the action level;
(iii) The purpose, proper selection, fitting, use, and limitations
of respirators;
(iv) The purpose and a description of the medical surveillance
program, and the medical removal protection program including
information concerning the adverse health effects associated with
excessive exposure to lead (with particular attention to the adverse
reproductive effects on both males and females and hazards to the fetus
and additional precautions for employees who are pregnant);
(v) The engineering controls and work practices associated with the
employee's job assignment including training of employees to follow
relevant good work practices described in Appendix B of this section;
(vi) The contents of any compliance plan in effect;
(vii) Instructions to employees that chelating agents should not
routinely be used to remove lead from their bodies and should not be
used at all except under the direction of a licensed physician; and
(viii) The employee's right of access to records under 29 CFR
1910.20.
(3) Access to information and training materials. (i) The employer
shall make readily available to all affected employees a copy of this
standard and its appendices.
(ii) The employer shall provide, upon request, all materials
relating to the employee information and training program to affected
employees and their designated representatives, and to the Assistant
Secretary and the Director.
(m) Signs--(1) General. (i) The employer may use signs required by
other statutes, regulations or ordinances in addition to, or in
combination with, signs required by this paragraph.
(ii) The employer shall assure that no statement appears on or near
any sign required by this paragraph which contradicts or detracts from
the meaning of the required sign.
(2) Signs. (i) The employer shall post the following warning signs
in each work area where an employees exposure to lead is above the PEL.
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
(ii) The employer shall assure that signs required by this paragraph
are illuminated and cleaned as necessary so that the legend is readily
visible.
(n) Recordkeeping--(1) Exposure assessment. (i) The employer shall
establish and maintain an accurate record of all monitoring and other
data used in conducting employee exposure assessments as required in
paragraph (d) of this section.
(ii) Exposure monitoring records shall include:
(A) The date(s), number, duration, location and results of each of
the samples taken if any, including a description of the sampling
procedure used to determine representative employee exposure where
applicable;
(B) A description of the sampling and analytical methods used and
evidence of their accuracy;
(C) The type of respiratory protective devices worn, if any;
(D) Name, social security number, and job classification of the
employee monitored and of all other employees whose exposure the
measurement is intended to represent; and
(E) The environmental variables that could affect the measurement of
employee exposure.
(iii) The employer shall maintain monitoring and other exposure
assessment records in accordance with the provisions of 29 CFR 1910.33.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (j) of this section.
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(ii) This record shall include:
(A) The name, social security number, and description of the duties
of the employee;
(B) A copy of the physician's written opinions;
(C) Results of any airborne exposure monitoring done on or for that
employee and provided to the physician; and
(D) Any employee medical complaints related to exposure to lead.
(iii) The employer shall keep, or assure that the examining
physician keeps, the following medical records:
(A) A copy of the medical examination results including medical and
work history required under paragraph (j) of this section;
(B) A description of the laboratory procedures and a copy of any
standards or guidelines used to interpret the test results or references
to that information;
(C) A copy of the results of biological monitoring.
(iv) The employer shall maintain or assure that the physician
maintains medical records in accordance with the provisions of 29 CFR
1910.33.
(3) Medical removals. (i) The employer shall establish and maintain
an accurate record for each employee removed from current exposure to
lead pursuant to paragraph (k) of this section.
(ii) Each record shall include:
(A) The name and social security number of the employee;
(B) The date of each occasion that the employee was removed from
current exposure to lead as well as the corresponding date on which the
employee was returned to his or her former job status;
(C) A brief explanation of how each removal was or is being
accomplished; and
(D) A statement with respect to each removal indicating whether or
not the reason for the removal was an elevated blood lead level.
(iii) The employer shall maintain each medical removal record for at
least the duration of an employee's employment.
(4) Objective data for exemption from requirement for initial
monitoring. (i) For purposes of this section, objective data are
information demonstrating that a particular product or material
containing lead or a specific process, operation, or activity involving
lead cannot release dust or fumes in concentrations at or above the
action level under any expected conditions of use. Objective data can be
obtained from an industry-wide study or from laboratory product test
results from manufacturers of lead containing products or materials. The
data the employer uses from an industry-wide survey must be obtained
under workplace conditions closely resembling the processes, types of
material, control methods, work practices and environmental conditions
in the employer's current operations.
(ii) The employer shall maintain the record of the objective data
relied upon for at least 30 years.
(5) Availability. The employer shall make available upon request all
records required to be maintained by paragraph (n) of this section to
affected employees, former employees, and their designated
representatives, and to the Assistant Secretary and the Director for
examination and copying.
(6) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by paragraph (n) of this section.
(ii) Whenever the employer ceases to do business and there is no
successor employer to receive and retain the records required to be
maintained by this section for the prescribed period, these records
shall be transmitted to the Director.
(iii) At the expiration of the retention period for the records
required to be maintained by this section, the employer shall notify the
Director at least 3 months prior to the disposal of such records and
shall transmit those records to the Director if requested within the
period.
(iv) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.33(h).
(o) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to lead conducted
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pursuant to paragraph (d) of this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to lead requires entry into an area
where the use of respirators, protective clothing or equipment is
required, the employer shall provide the observer with and assure the
use of such respirators, clothing and equipment, and shall require the
observer to comply with all other applicable safety and health
procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled to:
(A) Receive an explanation of the measurement procedures;
(B) Observe all steps related to the monitoring of lead performed at
the place of exposure; and
(C) Record the results obtained or receive copies of the results
when returned by the laboratory.
(p) Appendices. The information contained in the appendices to this
section is not intended by itself, to create any additional obligations
not otherwise imposed by this standard nor detract from any existing
obligation.
Appendix A to Sec. 1926.62--Substance Data Sheet for Occupational
Exposure to Lead
I. Substance Identification
A. Substance: Pure lead (Pb) is a heavy metal at room temperature
and pressure and is a basic chemical element. It can combine with
various other substances to form numerous lead compounds.
B. Compounds covered by the standard: The word lead when used in
this interim final standard means elemental lead, all inorganic lead
compounds and a class of organic lead compounds called lead soaps. This
standard does not apply to other organic lead compounds.
C. Uses: Exposure to lead occurs in several different occupations in
the construction industry, including demolition or salvage of structures
where lead or lead-containing materials are present; removal or
encapsulation of lead-containing materials, new construction,
alteration, repair, or renovation of structures that contain lead or
materials containing lead; installation of products containing lead. In
addition, there are construction related activities where exposure to
lead may occur, including transportation, disposal, storage, or
containment of lead or materials containing lead on construction sites,
and maintenance operations associated with construction activities.
D. Permissible exposure: The permissible exposure limit (PEL) set by
the standard is 50 micrograms of lead per cubic meter of air (50
[micro]g/m\3\), averaged over an 8-hour workday.
E. Action level: The interim final standard establishes an action
level of 30 micrograms of lead per cubic meter of air (30 [micro]g/
m\3\), averaged over an 8-hour workday. The action level triggers
several ancillary provisions of the standard such as exposure
monitoring, medical surveillance, and training.
II. Health Hazard Data
A. Ways in which lead enters your body. When absorbed into your body
in certain doses, lead is a toxic substance. The object of the lead
standard is to prevent absorption of harmful quantities of lead. The
standard is intended to protect you not only from the immediate toxic
effects of lead, but also from the serious toxic effects that may not
become apparent until years of exposure have passed. Lead can be
absorbed into your body by inhalation (breathing) and ingestion
(eating). Lead (except for certain organic lead compounds not covered by
the standard, such as tetraethyl lead) is not absorbed through your
skin. When lead is scattered in the air as a dust, fume respiratory
tract. Inhalation of airborne lead is generally the most important
source of occupational lead absorption. You can also absorb lead through
your digestive system if lead gets into your mouth and is swallowed. If
you handle food, cigarettes, chewing tobacco, or make-up which have lead
on them or handle them with hands contaminated with lead, this will
contribute to ingestion. A significant portion of the lead that you
inhale or ingest gets into your blood stream. Once in your blood stream,
lead is circulated throughout your body and stored in various organs and
body tissues. Some of this lead is quickly filtered out of your body and
excreted, but some remains in the blood and other tissues. As exposure
to lead continues, the amount stored in your body will increase if you
are absorbing more lead than your body is excreting. Even though you may
not be aware of any immediate symptoms of disease, this lead stored in
your tissues can be slowly causing irreversible damage, first to
individual cells, then to your organs and whole body systems.
B. Effects of overexposure to lead--(1) Short term (acute)
overexposure. Lead is a potent, systemic poison that serves no known
useful function once absorbed by your body. Taken in large enough doses,
lead can kill you in a matter of days. A condition affecting the brain
called acute encephalopathy may arise which develops quickly to
seizures, coma, and death from cardiorespiratory arrest. A short term
dose of lead can lead to acute
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encephalopathy. Short term occupational exposures of this magnitude are
highly unusual, but not impossible. Similar forms of encephalopathy may,
however, arise from extended, chronic exposure to lower doses of lead.
There is no sharp dividing line between rapidly developing acute effects
of lead, and chronic effects which take longer to acquire. Lead
adversely affects numerous body systems, and causes forms of health
impairment and disease which arise after periods of exposure as short as
days or as long as several years.
(2) Long-term (chronic) overexposure. Chronic overexposure to lead
may result in severe damage to your blood-forming, nervous, urinary and
reproductive systems. Some common symptoms of chronic overexposure
include loss of appetite, metallic taste in the mouth, anxiety,
constipation, nausea, pallor, excessive tiredness, weakness, insomnia,
headache, nervous irritability, muscle and joint pain or soreness, fine
tremors, numbness, dizziness, hyperactivity and colic. In lead colic
there may be severe abdominal pain. Damage to the central nervous system
in general and the brain (encephalopathy) in particular is one of the
most severe forms of lead poisoning. The most severe, often fatal, form
of encephalopathy may be preceded by vomiting, a feeling of dullness
progressing to drowsiness and stupor, poor memory, restlessness,
irritability, tremor, and convulsions. It may arise suddenly with the
onset of seizures, followed by coma, and death. There is a tendency for
muscular weakness to develop at the same time. This weakness may
progress to paralysis often observed as a characteristic ``wrist drop''
or ``foot drop'' and is a manifestation of a disease to the nervous
system called peripheral neuropathy. Chronic overexposure to lead also
results in kidney disease with few, if any, symptoms appearing until
extensive and most likely permanent kidney damage has occurred. Routine
laboratory tests reveal the presence of this kidney disease only after
about two-thirds of kidney function is lost. When overt symptoms of
urinary dysfunction arise, it is often too late to correct or prevent
worsening conditions, and progression to kidney dialysis or death is
possible. Chronic overexposure to lead impairs the reproductive systems
of both men and women. Overexposure to lead may result in decreased sex
drive, impotence and sterility in men. Lead can alter the structure of
sperm cells raising the risk of birth defects. There is evidence of
miscarriage and stillbirth in women whose husbands were exposed to lead
or who were exposed to lead themselves. Lead exposure also may result in
decreased fertility, and abnormal menstrual cycles in women. The course
of pregnancy may be adversely affected by exposure to lead since lead
crosses the placental barrier and poses risks to developing fetuses.
Children born of parents either one of whom were exposed to excess lead
levels are more likely to have birth defects, mental retardation,
behavioral disorders or die during the first year of childhood.
Overexposure to lead also disrupts the blood-forming system resulting in
decreased hemoglobin (the substance in the blood that carries oxygen to
the cells) and ultimately anemia. Anemia is characterized by weakness,
pallor and fatigability as a result of decreased oxygen carrying
capacity in the blood.
(3) Health protection goals of the standard. Prevention of adverse
health effects for most workers from exposure to lead throughout a
working lifetime requires that a worker's blood lead level (BLL, also
expressed as PbB) be maintained at or below forty micrograms per
deciliter of whole blood (40 [micro]g/dl). The blood lead levels of
workers (both male and female workers) who intend to have children
should be maintained below 30 [micro]g/dl to minimize adverse
reproductive health effects to the parents and to the developing fetus.
The measurement of your blood lead level (BLL) is the most useful
indicator of the amount of lead being absorbed by your body. Blood lead
levels are most often reported in units of milligrams (mg) or micrograms
([micro]g) of lead (1 mg=1000 [micro]g) per 100 grams (100g), 100
milliliters (100 ml) or deciliter (dl) of blood. These three units are
essentially the same. Sometime BLLs are expressed in the form of mg% or
[micro]g%. This is a shorthand notation for 100g, 100 ml, or dl.
(References to BLL measurements in this standard are expressed in the
form of [micro]g/dl.)
BLL measurements show the amount of lead circulating in your blood
stream, but do not give any information about the amount of lead stored
in your various tissues. BLL measurements merely show current absorption
of lead, not the effect that lead is having on your body or the effects
that past lead exposure may have already caused. Past research into
lead-related diseases, however, has focused heavily on associations
between BLLs and various diseases. As a result, your BLL is an important
indicator of the likelihood that you will gradually acquire a lead-
related health impairment or disease.
Once your blood lead level climbs above 40 [micro]g/dl, your risk of
disease increases. There is a wide variability of individual response to
lead, thus it is difficult to say that a particular BLL in a given
person will cause a particular effect. Studies have associated fatal
encephalopathy with BLLs as low as 150 [micro]g/dl. Other studies have
shown other forms of diseases in some workers with BLLs well below 80
[micro]g/dl. Your BLL is a crucial indicator of the risks to your
health, but one other factor is also extremely important. This factor is
the length of time you have had elevated BLLs. The longer you have an
elevated BLL, the greater the risk that large quantities of lead are
being gradually stored
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in your organs and tissues (body burden). The greater your overall body
burden, the greater the chances of substantial permanent damage. The
best way to prevent all forms of lead-related impairments and diseases--
both short term and long term--is to maintain your BLL below 40
[micro]g/dl. The provisions of the standard are designed with this end
in mind.
Your employer has prime responsibility to assure that the provisions
of the standard are complied with both by the company and by individual
workers. You, as a worker, however, also have a responsibility to assist
your employer in complying with the standard. You can play a key role in
protecting your own health by learning about the lead hazards and their
control, learning what the standard requires, following the standard
where it governs your own actions, and seeing that your employer
complies with provisions governing his or her actions.
(4) Reporting signs and symptoms of health problems. You should
immediately notify your employer if you develop signs or symptoms
associated with lead poisoning or if you desire medical advice
concerning the effects of current or past exposure to lead or your
ability to have a healthy child. You should also notify your employer if
you have difficulty breathing during a respirator fit test or while
wearing a respirator. In each of these cases, your employer must make
available to you appropriate medical examinations or consultations.
These must be provided at no cost to you and at a reasonable time and
place. The standard contains a procedure whereby you can obtain a second
opinion by a physician of your choice if your employer selected the
initial physician.
Appendix B to Sec. 1926.62--Employee Standard Summary
This appendix summarizes key provisions of the interim final
standard for lead in construction that you as a worker should become
familiar with.
I. Permissible Exposure Limit (PEL)--Paragraph (C)
The standard sets a permissible exposure limit (PEL) of 50
micrograms of lead per cubic meter of air (50 [micro]g/m\3\), averaged
over an 8-hour workday which is referred to as a time-weighted average
(TWA). This is the highest level of lead in air to which you may be
permissibly exposed over an 8-hour workday. However, since this is an 8-
hour average, short exposures above the PEL are permitted so long as for
each 8-hour work day your average exposure does not exceed this level.
This interim final standard, however, takes into account the fact that
your daily exposure to lead can extend beyond a typical 8-hour workday
as the result of overtime or other alterations in your work schedule. To
deal with this situation, the standard contains a formula which reduces
your permissible exposure when you are exposed more than 8 hours. For
example, if you are exposed to lead for 10 hours a day, the maximum
permitted average exposure would be 40 [micro]g/m\3\.
II. Exposure Assessment--Paragraph (D)
If lead is present in your workplace in any quantity, your employer
is required to make an initial determination of whether any employee's
exposure to lead exceeds the action level (30 [micro]g/m\3\ averaged
over an 8-hour day). Employee exposure is that exposure which would
occur if the employee were not using a respirator. This initial
determination requires your employer to monitor workers' exposures
unless he or she has objective data which can demonstrate conclusively
that no employee will be exposed to lead in excess of the action level.
Where objective data is used in lieu of actual monitoring the employer
must establish and maintain an accurate record, documenting its
relevancy in assessing exposure levels for current job conditions. If
such objective data is available, the employer need proceed no further
on employee exposure assessment until such time that conditions have
changed and the determination is no longer valid.
Objective data may be compiled from various sources, e.g., insurance
companies and trade associations and information from suppliers or
exposure data collected from similar operations. Objective data may also
comprise previously-collected sampling data including area monitoring.
If it cannot be determined through using objective data that worker
exposure is less than the action level, your employer must conduct
monitoring or must rely on relevant previous personal sampling, if
available. Where monitoring is required for the initial determination,
it may be limited to a representative number of employees who are
reasonably expected to have the highest exposure levels. If your
employer has conducted appropriate air sampling for lead in the past 12
months, he or she may use these results, provided they are applicable to
the same employee tasks and exposure conditions and meet the
requirements for accuracy as specified in the standard. As with
objective data, if such results are relied upon for the initial
determination, your employer must establish and maintain a record as to
the relevancy of such data to current job conditions.
If there have been any employee complaints of symptoms which may be
attributable to exposure to lead or if there is any other information or
observations which would indicate employee exposure to lead, this must
also be considered as part of the initial determination.
If this initial determination shows that a reasonable possibility
exists that any employee may be exposed, without regard to
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respirators, over the action level, your employer must set up an air
monitoring program to determine the exposure level representative of
each employee exposed to lead at your workplace. In carrying out this
air monitoring program, your employer is not required to monitor the
exposure of every employee, but he or she must monitor a representative
number of employees and job types. Enough sampling must be done to
enable each employee's exposure level to be reasonably represent full
shift exposure. In addition, these air samples must be taken under
conditions which represent each employee's regular, daily exposure to
lead. Sampling performed in the past 12 months may be used to determine
exposures above the action level if such sampling was conducted during
work activities essentially similar to present work conditions.
The standard lists certain tasks which may likely result in
exposures to lead in excess of the PEL and, in some cases, exposures in
excess of 50 times the PEL. If you are performing any of these tasks,
your employer must provide you with appropriate respiratory protection,
protective clothing and equipment, change areas, hand washing
facilities, biological monitoring, and training until such time that an
exposure assessment is conducted which demonstrates that your exposure
level is below the PEL.
If you are exposed to lead and air sampling is performed, your
employer is required to notify you in writing within 5 working days of
the air monitoring results which represent your exposure. If the results
indicate that your exposure exceeds the PEL (without regard to your use
of a respirator), then your employer must also notify you of this in
writing, and provide you with a description of the corrective action
that has been taken or will be taken to reduce your exposure.
Your exposure must be rechecked by monitoring, at least every six
months if your exposure is at or over the action level but below the
PEL. Your employer may discontinue monitoring for you if 2 consecutive
measurements, taken at least 7 days apart, are at or below the action
level. Air monitoring must be repeated every 3 months if you are exposed
over the PEL. Your employer must continue monitoring for you at this
frequency until 2 consecutive measurements, taken at least 7 days apart,
are below the PEL but above the action level, at which time your
employer must repeat monitoring of your exposure every six months and
may discontinue monitoring only after your exposure drops to or below
the action level. However, whenever there is a change of equipment,
process, control, or personnel or a new type of job is added at your
workplace which may result in new or additional exposure to lead, your
employer must perform additional monitoring.
III. Methods of Compliance--Paragraph (E)
Your employer is required to assure that no employee is exposed to
lead in excess of the PEL as an 8-hour TWA. The interim final standard
for lead in construction requires employers to institute engineering and
work practice controls including administrative controls to the extent
feasible to reduce employee exposure to lead. Where such controls are
feasible but not adequate to reduce exposures below the PEL they must be
used nonetheless to reduce exposures to the lowest level that can be
accomplished by these means and then supplemented with appropriate
respiratory protection.
Your employer is required to develop and implement a written
compliance program prior to the commencement of any job where employee
exposures may reach the PEL as an 8-hour TWA. The interim final standard
identifies the various elements that must be included in the plan. For
example, employers are required to include a description of operations
in which lead is emitted, detailing other relevant information about the
operation such as the type of equipment used, the type of material
involved, employee job responsibilities, operating procedures and
maintenance practices. In addition, your employer's compliance plan must
specify the means that will be used to achieve compliance and, where
engineering controls are required, include any engineering plans or
studies that have been used to select the control methods. If
administrative controls involving job rotation are used to reduce
employee exposure to lead, the job rotation schedule must be included in
the compliance plan. The plan must also detail the type of protective
clothing and equipment, including respirators, housekeeping and hygiene
practices that will be used to protect you from the adverse effects of
exposure to lead.
The written compliance program must be made available, upon request,
to affected employees and their designated representatives, the
Assistant Secretary and the Director.
Finally, the plan must be reviewed and updated at least every 6
months to assure it reflects the current status in exposure control.
IV. Respiratory Protection--Paragraph (F)
Your employer is required to provide and assure your use of
respirators when your exposure to lead is not controlled below the PEL
by other means. The employer must pay the cost of the respirator.
Whenever you request one, your employer is also required to provide you
a respirator even if your air exposure level is not above the PEL. You
might desire a respirator when, for example, you have received medical
advice that your lead absorption should be decreased. Or, you may intend
to have children in the near future, and want to reduce the level of
lead in
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your body to minimize adverse reproductive effects. While respirators
are the least satisfactory means of controlling your exposure, they are
capable of providing significant protection if properly chosen, fitted,
worn, cleaned, maintained, and replaced when they stop providing
adequate protection.
Your employer is required to select respirators from the types
listed in Table I of the Respiratory Protection section of the standard
(Sec. 1926.62 (f)). Any respirator chosen must be approved by the
National Institute for Occupational Safety and Health (NIOSH) under the
provisions of 42 CFR part 84. This respirator selection table will
enable your employer to choose a type of respirator that will give you a
proper amount of protection based on your airborne lead exposure. Your
employer may select a type of respirator that provides greater
protection than that required by the standard; that is, one recommended
for a higher concentration of lead than is present in your workplace.
For example, a powered air-purifying respirator (PAPR) is much more
protective than a typical negative pressure respirator, and may also be
more comfortable to wear. A PAPR has a filter, cartridge, or canister to
clean the air, and a power source that continuously blows filtered air
into your breathing zone. Your employer might make a PAPR available to
you to ease the burden of having to wear a respirator for long periods
of time. The standard provides that you can obtain a PAPR upon request.
Your employer must also start a Respiratory Protection Program. This
program must include written procedures for the proper selection, use,
cleaning, storage, and maintenance of respirators.
Your employer must ensure that your respirator facepiece fits
properly. Proper fit of a respirator facepiece is critical to your
protection from airborne lead. Obtaining a proper fit on each employee
may require your employer to make available several different types of
respirator masks. To ensure that your respirator fits properly and that
facepiece leakage is minimal, your employer must give you either a
qualitative or quantitative fit test as specified in Appendix A of the
Respiratory Protection standard located at 29 CFR 1910.134.
You must also receive from your employer proper training in the use
of respirators. Your employer is required to teach you how to wear a
respirator, to know why it is needed, and to understand its limitations.
The standard provides that if your respirator uses filter elements,
you must be given an opportunity to change the filter elements whenever
an increase in breathing resistance is detected. You also must be
permitted to periodically leave your work area to wash your face and
respirator facepiece whenever necessary to prevent skin irritation. If
you ever have difficulty in breathing during a fit test or while using a
respirator, your employer must make a medical examination available to
you to determine whether you can safely wear a respirator. The result of
this examination may be to give you a positive pressure respirator
(which reduces breathing resistance) or to provide alternative means of
protection.
V. Protective Work Clothing and Equipment--Paragraph (G)
If you are exposed to lead above the PEL as an 8-hour TWA, without
regard to your use of a respirator, or if you are exposed to lead
compounds such as lead arsenate or lead azide which can cause skin and
eye irritation, your employer must provide you with protective work
clothing and equipment appropriate for the hazard. If work clothing is
provided, it must be provided in a clean and dry condition at least
weekly, and daily if your airborne exposure to lead is greater than 200
[micro]g/m\3\. Appropriate protective work clothing and equipment can
include coveralls or similar full-body work clothing, gloves, hats,
shoes or disposable shoe coverlets, and face shields or vented goggles.
Your employer is required to provide all such equipment at no cost to
you. In addition, your employer is responsible for providing repairs and
replacement as necessary, and also is responsible for the cleaning,
laundering or disposal of protective clothing and equipment.
The interim final standard requires that your employer assure that
you follow good work practices when you are working in areas where your
exposure to lead may exceed the PEL. With respect to protective clothing
and equipment, where appropriate, the following procedures should be
observed prior to beginning work:
1. Change into work clothing and shoe covers in the clean section of
the designated changing areas;
2. Use work garments of appropriate protective gear, including
respirators before entering the work area; and
3. Store any clothing not worn under protective clothing in the
designated changing area.
Workers should follow these procedures upon leaving the work area:
1. HEPA vacuum heavily contaminated protective work clothing while
it is still being worn. At no time may lead be removed from protective
clothing by any means which result in uncontrolled dispersal of lead
into the air;
2. Remove shoe covers and leave them in the work area;
3. Remove protective clothing and gear in the dirty area of the
designated changing area. Remove protective coveralls by carefully
rolling down the garment to reduce exposure to dust.
4. Remove respirators last; and
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5. Wash hands and face.
Workers should follow these procedures upon finishing work for the
day (in addition to procedures described above):
1. Where applicable, place disposal coveralls and shoe covers with
the abatement waste;
2. Contaminated clothing which is to be cleaned, laundered or
disposed of must be placed in closed containers in the change room.
3. Clean protective gear, including respirators, according to
standard procedures;
4. Wash hands and face again. If showers are available, take a
shower and wash hair. If shower facilities are not available at the work
site, shower immediately at home and wash hair.
VI. Housekeeping--Paragraph (H)
Your employer must establish a housekeeping program sufficient to
maintain all surfaces as free as practicable of accumulations of lead
dust. Vacuuming is the preferred method of meeting this requirement, and
the use of compressed air to clean floors and other surfaces is
generally prohibited unless removal with compressed air is done in
conjunction with ventilation systems designed to contain dispersal of
the lead dust. Dry or wet sweeping, shoveling, or brushing may not be
used except where vacuuming or other equally effective methods have been
tried and do not work. Vacuums must be used equipped with a special
filter called a high-efficiency particulate air (HEPA) filter and
emptied in a manner which minimizes the reentry of lead into the
workplace.
VII. Hygiene Facilities and Practices--Paragraph (I)
The standard requires that hand washing facilities be provided where
occupational exposure to lead occurs. In addition, change areas, showers
(where feasible), and lunchrooms or eating areas are to be made
available to workers exposed to lead above the PEL. Your employer must
assure that except in these facilities, food and beverage is not present
or consumed, tobacco products are not present or used, and cosmetics are
not applied, where airborne exposures are above the PEL. Change rooms
provided by your employer must be equipped with separate storage
facilities for your protective clothing and equipment and street clothes
to avoid cross-contamination. After showering, no required protective
clothing or equipment worn during the shift may be worn home. It is
important that contaminated clothing or equipment be removed in change
areas and not be worn home or you will extend your exposure and expose
your family since lead from your clothing can accumulate in your house,
car, etc.
Lunchrooms or eating areas may not be entered with protective
clothing or equipment unless surface dust has been removed by vacuuming,
downdraft booth, or other cleaning method. Finally, workers exposed
above the PEL must wash both their hands and faces prior to eating,
drinking, smoking or applying cosmetics.
All of the facilities and hygiene practices just discussed are
essential to minimize additional sources of lead absorption from
inhalation or ingestion of lead that may accumulate on you, your
clothes, or your possessions. Strict compliance with these provisions
can virtually eliminate several sources of lead exposure which
significantly contribute to excessive lead absorption.
VIII. Medical Surveillance--Paragraph (J)
The medical surveillance program is part of the standard's
comprehensive approach to the prevention of lead-related disease. Its
purpose is to supplement the main thrust of the standard which is aimed
at minimizing airborne concentrations of lead and sources of ingestion.
Only medical surveillance can determine if the other provisions of the
standard have affectively protected you as an individual. Compliance
with the standard's provision will protect most workers from the adverse
effects of lead exposure, but may not be satisfactory to protect
individual workers (1) who have high body burdens of lead acquired over
past years, (2) who have additional uncontrolled sources of non-
occupational lead exposure, (3) who exhibit unusual variations in lead
absorption rates, or (4) who have specific non-work related medical
conditions which could be aggravated by lead exposure (e.g., renal
disease, anemia). In addition, control systems may fail, or hygiene and
respirator programs may be inadequate. Periodic medical surveillance of
individual workers will help detect those failures. Medical surveillance
will also be important to protect your reproductive ability-regardless
of whether you are a man or woman.
All medical surveillance required by the interim final standard must
be performed by or under the supervision of a licensed physician. The
employer must provide required medical surveillance without cost to
employees and at a reasonable time and place. The standard's medical
surveillance program has two parts--periodic biological monitoring and
medical examinations. Your employer's obligation to offer you medical
surveillance is triggered by the results of the air monitoring program.
Full medical surveillance must be made available to all employees who
are or may be exposed to lead in excess of the action level for more
than 30 days a year and whose blood lead level exceeds 40 [micro]g/dl.
Initial medical surveillance consisting of blood sampling and analysis
for lead and zinc
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protoporphyrin must be provided to all employees exposed at any time (1
day) above the action level.
Biological monitoring under the standard must be provided at least
every 2 months for the first 6 months and every 6 months thereafter
until your blood lead level is below 40 [micro]g/dl. A zinc
protoporphyrin (ZPP) test is a very useful blood test which measures an
adverse metabolic effect of lead on your body and is therefore an
indicator of lead toxicity.
If your BLL exceeds 40 [micro]g/dl the monitoring frequency must be
increased from every 6 months to at least every 2 months and not reduced
until two consecutive BLLs indicate a blood lead level below 40
[micro]g/dl. Each time your BLL is determined to be over 40 [micro]g/dl,
your employer must notify you of this in writing within five working
days of his or her receipt of the test results. The employer must also
inform you that the standard requires temporary medical removal with
economic protection when your BLL exceeds 50 [micro]g/dl. (See
Discussion of Medical Removal Protection-Paragraph (k).) Anytime your
BLL exceeds 50 [micro]g/dl your employer must make available to you
within two weeks of receipt of these test results a second follow-up BLL
test to confirm your BLL. If the two tests both exceed 50 [micro]g/dl,
and you are temporarily removed, then your employer must make successive
BLL tests available to you on a monthly basis during the period of your
removal.
Medical examinations beyond the initial one must be made available
on an annual basis if your blood lead level exceeds 40 [micro]g/dl at
any time during the preceding year and you are being exposed above the
airborne action level of 30 [micro]g/m\3\ for 30 or more days per year.
The initial examination will provide information to establish a baseline
to which subsequent data can be compared.
An initial medical examination to consist of blood sampling and
analysis for lead and zinc protoporphyrin must also be made available
(prior to assignment) for each employee being assigned for the first
time to an area where the airborne concentration of lead equals or
exceeds the action level at any time. In addition, a medical examination
or consultation must be made available as soon as possible if you notify
your employer that you are experiencing signs or symptoms commonly
associated with lead poisoning or that you have difficulty breathing
while wearing a respirator or during a respirator fit test. You must
also be provided a medical examination or consultation if you notify
your employer that you desire medical advice concerning the effects of
current or past exposure to lead on your ability to procreate a healthy
child.
Finally, appropriate follow-up medical examinations or consultations
may also be provided for employees who have been temporarily removed
from exposure under the medical removal protection provisions of the
standard. (See Part IX, below.)
The standard specifies the minimum content of pre-assignment and
annual medical examinations. The content of other types of medical
examinations and consultations is left up to the sound discretion of the
examining physician. Pre-assignment and annual medical examinations must
include (1) a detailed work history and medical history; (2) a thorough
physical examination, including an evaluation of your pulmonary status
if you will be required to use a respirator; (3) a blood pressure
measurement; and (4) a series of laboratory tests designed to check your
blood chemistry and your kidney function. In addition, at any time upon
your request, a laboratory evaluation of male fertility will be made
(microscopic examination of a sperm sample), or a pregnancy test will be
given.
The standard does not require that you participate in any of the
medical procedures, tests, etc. which your employer is required to make
available to you. Medical surveillance can, however, play a very
important role in protecting your health. You are strongly encouraged,
therefore, to participate in a meaningful fashion. The standard contains
a multiple physician review mechanism which will give you a chance to
have a physician of your choice directly participate in the medical
surveillance program. If you are dissatisfied with an examination by a
physician chosen by your employer, you can select a second physician to
conduct an independent analysis. The two doctors would attempt to
resolve any differences of opinion, and select a third physician to
resolve any firm dispute. Generally your employer will choose the
physician who conducts medical surveillance under the lead standard-
unless you and your employer can agree on the choice of a physician or
physicians. Some companies and unions have agreed in advance, for
example, to use certain independent medical laboratories or panels of
physicians. Any of these arrangements are acceptable so long as required
medical surveillance is made available to workers.
The standard requires your employer to provide certain information
to a physician to aid in his or her examination of you. This information
includes (1) the standard and its appendices, (2) a description of your
duties as they relate to occupational lead exposure, (3) your exposure
level or anticipated exposure level, (4) a description of any personal
protective equipment you wear, (5) prior blood lead level results, and
(6) prior written medical opinions concerning you that the employer has.
After a medical examination or consultation the physician must prepare a
written report which must contain (1) the physician's opinion as to
whether you have any medical condition which places you at increased
risk of material impairment to
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health from exposure to lead, (2) any recommended special protective
measures to be provided to you, (3) any blood lead level determinations,
and (4) any recommended limitation on your use of respirators. This last
element must include a determination of whether you can wear a powered
air purifying respirator (PAPR) if you are found unable to wear a
negative pressure respirator.
The medical surveillance program of the interim lead standard may at
some point in time serve to notify certain workers that they have
acquired a disease or other adverse medical condition as a result of
occupational lead exposure. If this is true, these workers might have
legal rights to compensation from public agencies, their employers,
firms that supply hazardous products to their employers, or other
persons. Some states have laws, including worker compensation laws, that
disallow a worker who learns of a job-related health impairment to sue,
unless the worker sues within a short period of time after learning of
the impairment. (This period of time may be a matter of months or
years.) An attorney can be consulted about these possibilities. It
should be stressed that OSHA is in no way trying to either encourage or
discourage claims or lawsuits. However, since results of the standard's
medical surveillance program can significantly affect the legal remedies
of a worker who has acquired a job-related disease or impairment, it is
proper for OSHA to make you aware of this.
The medical surveillance section of the standard also contains
provisions dealing with chelation. Chelation is the use of certain drugs
(administered in pill form or injected into the body) to reduce the
amount of lead absorbed in body tissues. Experience accumulated by the
medical and scientific communities has largely confirmed the
effectiveness of this type of therapy for the treatment of very severe
lead poisoning. On the other hand, it has also been established that
there can be a long list of extremely harmful side effects associated
with the use of chelating agents. The medical community has balanced the
advantages and disadvantages resulting from the use of chelating agents
in various circumstances and has established when the use of these
agents is acceptable. The standard includes these accepted limitations
due to a history of abuse of chelation therapy by some lead companies.
The most widely used chelating agents are calcium disodium EDTA, (Ca Na2
EDTA), Calcium Disodium Versenate (Versenate), and d-penicillamine
(pencillamine or Cupramine).
The standard prohibits ``prophylactic chelation'' of any employee by
any person the employer retains, supervises or controls. Prophylactic
chelation is the routine use of chelating or similarly acting drugs to
prevent elevated blood levels in workers who are occupationally exposed
to lead, or the use of these drugs to routinely lower blood lead levels
to predesignated concentrations believed to be ``safe''. It should be
emphasized that where an employer takes a worker who has no symptoms of
lead poisoning and has chelation carried out by a physician (either
inside or outside of a hospital) solely to reduce the worker's blood
lead level, that will generally be considered prophylactic chelation.
The use of a hospital and a physician does not mean that prophylactic
chelation is not being performed. Routine chelation to prevent increased
or reduce current blood lead levels is unacceptable whatever the
setting.
The standard allows the use of ``therapeutic'' or ``diagnostic''
chelation if administered under the supervision of a licensed physician
in a clinical setting with thorough and appropriate medical monitoring.
Therapeutic chelation responds to severe lead poisoning where there are
marked symptoms. Diagnostic chelation involved giving a patient a dose
of the drug then collecting all urine excreted for some period of time
as an aid to the diagnosis of lead poisoning.
In cases where the examining physician determines that chelation is
appropriate, you must be notified in writing of this fact before such
treatment. This will inform you of a potentially harmful treatment, and
allow you to obtain a second opinion.
IX. Medical Removal Protection--Paragraph (K)
Excessive lead absorption subjects you to increased risk of disease.
Medical removal protection (MRP) is a means of protecting you when, for
whatever reasons, other methods, such as engineering controls, work
practices, and respirators, have failed to provide the protection you
need. MRP involves the temporary removal of a worker from his or her
regular job to a place of significantly lower exposure without any loss
of earnings, seniority, or other employment rights or benefits. The
purpose of this program is to cease further lead absorption and allow
your body to naturally excrete lead which has previously been absorbed.
Temporary medical removal can result from an elevated blood lead level,
or a medical opinion. For up to 18 months, or for as long as the job the
employee was removed from lasts, protection is provided as a result of
either form of removal. The vast majority of removed workers, however,
will return to their former jobs long before this eighteen month period
expires.
You may also be removed from exposure even if your blood lead level
is below 50 [micro]g/dl if a final medical determination indicates that
you temporarily need reduced lead exposure for medical reasons. If the
physician who is implementing your employers medical program makes a
final written opinion
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recommending your removal or other special protective measures, your
employer must implement the physician's recommendation. If you are
removed in this manner, you may only be returned when the doctor
indicates that it is safe for you to do so.
The standard does not give specific instructions dealing with what
an employer must do with a removed worker. Your job assignment upon
removal is a matter for you, your employer and your union (if any) to
work out consistent with existing procedures for job assignments. Each
removal must be accomplished in a manner consistent with existing
collective bargaining relationships. Your employer is given broad
discretion to implement temporary removals so long as no attempt is made
to override existing agreements. Similarly, a removed worker is provided
no right to veto an employer's choice which satisfies the standard.
In most cases, employers will likely transfer removed employees to
other jobs with sufficiently low lead exposure. Alternatively, a
worker's hours may be reduced so that the time weighted average exposure
is reduced, or he or she may be temporarily laid off if no other
alternative is feasible.
In all of these situation, MRP benefits must be provided during the
period of removal--i.e., you continue to receive the same earnings,
seniority, and other rights and benefits you would have had if you had
not been removed. Earnings includes more than just your base wage; it
includes overtime, shift differentials, incentives, and other
compensation you would have earned if you had not been removed. During
the period of removal you must also be provided with appropriate follow-
up medical surveillance. If you were removed because your blood lead
level was too high, you must be provided with a monthly blood test. If a
medical opinion caused your removal, you must be provided medical tests
or examinations that the doctor believes to be appropriate. If you do
not participate in this follow up medical surveillance, you may lose
your eligibility for MRP benefits.
When you are medically eligible to return to your former job, your
employer must return you to your ``former job status.'' This means that
you are entitled to the position, wages, benefits, etc., you would have
had if you had not been removed. If you would still be in your old job
if no removal had occurred that is where you go back. If not, you are
returned consistent with whatever job assignment discretion your
employer would have had if no removal had occurred. MRP only seeks to
maintain your rights, not expand them or diminish them.
If you are removed under MRP and you are also eligible for worker
compensation or other compensation for lost wages, your employer's MRP
benefits obligation is reduced by the amount that you actually receive
from these other sources. This is also true if you obtain other
employment during the time you are laid off with MRP benefits.
The standard also covers situations where an employer voluntarily
removes a worker from exposure to lead due to the effects of lead on the
employee's medical condition, even though the standard does not require
removal. In these situations MRP benefits must still be provided as
though the standard required removal. Finally, it is important to note
that in all cases where removal is required, respirators cannot be used
as a substitute. Respirators may be used before removal becomes
necessary, but not as an alternative to a transfer to a low exposure
job, or to a lay-off with MRP benefits.
X. Employee Information and Training--Paragraph (L)
Your employer is required to provide an information and training
program for all employees exposed to lead above the action level or who
may suffer skin or eye irritation from lead compounds such as lead
arsenate or lead azide. The program must train these employees regarding
the specific hazards associated with their work environment, protective
measures which can be taken, including the contents of any compliance
plan in effect, the danger of lead to their bodies (including their
reproductive systems), and their rights under the standard. All
employees must be trained prior to initial assignment to areas where
there is a possibility of exposure over the action level.
This training program must also be provided at least annually
thereafter unless further exposure above the action level will not
occur.
XI. Signs--Paragraph (M)
The standard requires that the following warning sign be posted in
work areas where the exposure to lead exceeds the PEL:
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
These signs are to be posted and maintained in a manner which
assures that the legend is readily visible.
XII. Recordkeeping--Paragraph (N)
Your employer is required to keep all records of exposure monitoring
for airborne lead. These records must include the name and job
classification of employees measured, details of the sampling and
analytical techniques, the results of this sampling, and the type of
respiratory protection being worn by the person sampled. Such records
are to be retained for at least 30 years. Your employer is also required
to keep all records
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of biological monitoring and medical examination results. These records
must include the names of the employees, the physician's written
opinion, and a copy of the results of the examination. Medical records
must be preserved and maintained for the duration of employment plus 30
years. However, if the employee's duration of employment is less than
one year, the employer need not retain that employee's medical records
beyond the period of employment if they are provided to the employee
upon termination of employment.
Recordkeeping is also required if you are temporarily removed from
your job under the medical removal protection program. This record must
include your name and social security number, the date of your removal
and return, how the removal was or is being accomplished, and whether or
not the reason for the removal was an elevated blood lead level. Your
employer is required to keep each medical removal record only for as
long as the duration of an employee's employment.
The standard requires that if you request to see or copy
environmental monitoring, blood lead level monitoring, or medical
removal records, they must be made available to you or to a
representative that you authorize. Your union also has access to these
records. Medical records other than BLL's must also be provided upon
request to you, to your physician or to any other person whom you may
specifically designate. Your union does not have access to your personal
medical records unless you authorize their access.
XIII. Observation of Monitoring--Paragraph (O)
When air monitoring for lead is performed at your workplace as
required by this standard, your employer must allow you or someone you
designate to act as an observer of the monitoring. Observers are
entitled to an explanation of the measurement procedure, and to record
the results obtained. Since results will not normally be available at
the time of the monitoring, observers are entitled to record or receive
the results of the monitoring when returned by the laboratory. Your
employer is required to provide the observer with any personal
protective devices required to be worn by employees working in the area
that is being monitored. The employer must require the observer to wear
all such equipment and to comply with all other applicable safety and
health procedures.
XIV. For Additional Information
A. A copy of the interim standard for lead in construction can be
obtained free of charge by calling or writing the OSHA Office of
Publications, room N-3101, United States Department of Labor,
Washington, DC 20210: Telephone (202) 219-4667.
B. Additional information about the standard, its enforcement, and
your employer's compliance can be obtained from the nearest OSHA Area
Office listed in your telephone directory under United States
Government/Department of Labor.
Appendix C to Sec. 1926.62--Medical Surveillance Guidelines
Introduction
The primary purpose of the Occupational Safety and Health Act of
1970 is to assure, so far as possible, safe and healthful working
conditions for every working man and woman. The interim final
occupational health standard for lead in construction is designed to
protect workers exposed to inorganic lead including metallic lead, all
inorganic lead compounds and organic lead soaps.
Under this interim final standard occupational exposure to inorganic
lead is to be limited to 50 [micro]g/m\3\ (micrograms per cubic meter)
based on an 8 hour time-weighted average (TWA). This permissible
exposure limit (PEL) must be achieved through a combination of
engineering, work practice and administrative controls to the extent
feasible. Where these controls are in place but are found not to reduce
employee exposures to or below the PEL, they must be used nonetheless,
and supplemented with respirators to meet the 50 [micro]g/m\3\ exposure
limit.
The standard also provides for a program of biological monitoring
for employees exposed to lead above the action level at any time, and
additional medical surveillance for all employees exposed to levels of
inorganic lead above 30 [micro]g/m\3\ (TWA) for more than 30 days per
year and whose BLL exceeds 40 [micro]g/dl.
The purpose of this document is to outline the medical surveillance
provisions of the interim standard for inorganic lead in construction,
and to provide further information to the physician regarding the
examination and evaluation of workers exposed to inorganic lead.
Section 1 provides a detailed description of the monitoring
procedure including the required frequency of blood testing for exposed
workers, provisions for medical removal protection (MRP), the
recommended right of the employee to a second medical opinion, and
notification and recordkeeping requirements of the employer. A
discussion of the requirements for respirator use and respirator
monitoring and OSHA's position on prophylactic chelation therapy are
also included in this section.
Section 2 discusses the toxic effects and clinical manifestations of
lead poisoning and effects of lead intoxication on enzymatic
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pathways in heme synthesis. The adverse effects on both male and female
reproductive capacity and on the fetus are also discussed.
Section 3 outlines the recommended medical evaluation of the worker
exposed to inorganic lead, including details of the medical history,
physical examination, and recommended laboratory tests, which are based
on the toxic effects of lead as discussed in Section 2.
Section 4 provides detailed information concerning the laboratory
tests available for the monitoring of exposed workers. Included also is
a discussion of the relative value of each test and the limitations and
precautions which are necessary in the interpretation of the laboratory
results.
I. Medical Surveillance and Monitoring Requirements for Workers Exposed
to Inorganic Lead
Under the interim final standard for inorganic lead in the
construction industry, initial medical surveillance consisting of
biological monitoring to include blood lead and ZPP level determination
shall be provided to employees exposed to lead at or above the action
level on any one day. In addition, a program of biological monitoring is
to be made available to all employees exposed above the action level at
any time and additional medical surveillance is to be made available to
all employees exposed to lead above 30 [micro]g/m\3\ TWA for more than
30 days each year and whose BLL exceeds 40 [micro]g/dl. This program
consists of periodic blood sampling and medical evaluation to be
performed on a schedule which is defined by previous laboratory results,
worker complaints or concerns, and the clinical assessment of the
examining physician.
Under this program, the blood lead level (BLL) of all employees who
are exposed to lead above 30 [micro]g/m\3\ for more than 30 days per
year or whose blood lead is above 40 [micro]g/dl but exposed for no more
than 30 days per year is to be determined at least every two months for
the first six months of exposure and every six months thereafter. The
frequency is increased to every two months for employees whose last
blood lead level was 40 [micro]g/dl or above. For employees who are
removed from exposure to lead due to an elevated blood lead, a new blood
lead level must be measured monthly. A zinc protoporphyrin (ZPP)
measurement is strongly recommended on each occasion that a blood lead
level measurement is made.
An annual medical examination and consultation performed under the
guidelines discussed in Section 3 is to be made available to each
employee exposed above 30 [micro]g/m\3\ for more than 30 days per year
for whom a blood test conducted at any time during the preceding 12
months indicated a blood lead level at or above 40 [micro]g/dl. Also, an
examination is to be given to all employees prior to their assignment to
an area in which airborne lead concentrations reach or exceed the 30
[micro]g/m\3\ for more than 30 days per year. In addition, a medical
examination must be provided as soon as possible after notification by
an employee that the employee has developed signs or symptoms commonly
associated with lead intoxication, that the employee desires medical
advice regarding lead exposure and the ability to procreate a healthy
child, or that the employee has demonstrated difficulty in breathing
during a respirator fitting test or during respirator use. An
examination is also to be made available to each employee removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited or specially protected pursuant to medical
recommendations.
Results of biological monitoring or the recommendations of an
examining physician may necessitate removal of an employee from further
lead exposure pursuant to the standard's medical removal protection
(MRP) program. The object of the MRP program is to provide temporary
medical removal to workers either with substantially elevated blood lead
levels or otherwise at risk of sustaining material health impairment
from continued substantial exposure to lead.
Under the standard's ultimate worker removal criteria, a worker is
to be removed from any work having an eight hour TWA exposure to lead of
30 [micro]g/m\3\ when his or her blood lead level reaches 50 [micro]g/dl
and is confirmed by a second follow-up blood lead level performed within
two weeks after the employer receives the results of the first blood
sampling test. Return of the employee to his or her job status depends
on a worker's blood lead level declining to 40 [micro]g/dl.
As part of the interim standard, the employer is required to notify
in writing each employee whose blood lead level exceeds 40 [micro]g/dl.
In addition each such employee is to be informed that the standard
requires medical removal with MRP benefits, discussed below, when an
employee's blood lead level exceeds the above defined limit.
In addition to the above blood lead level criterion, temporary
worker removal may also take place as a result of medical determinations
and recommendations. Written medical opinions must be prepared after
each examination pursuant to the standard. If the examining physician
includes a medical finding, determination or opinion that the employee
has a medical condition which places the employee at increased risk of
material health impairment from exposure to lead, then the employee must
be removed from exposure to lead at or above 30 [micro]g/m\3\.
Alternatively, if the examining physician recommends special protective
measures for an employee (e.g., use of a powered air purifying
respirator) or recommends limitations
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on an employee's exposure to lead, then the employer must implement
these recommendations.
Recommendations may be more stringent than the specific provisions
of the standard. The examining physician, therefore, is given broad
flexibility to tailor special protective procedures to the needs of
individual employees. This flexibility extends to the evaluation and
management of pregnant workers and male and female workers who are
planning to raise children. Based on the history, physical examination,
and laboratory studies, the physician might recommend special protective
measures or medical removal for an employee who is pregnant or who is
planning to conceive a child when, in the physician's judgment,
continued exposure to lead at the current job would pose a significant
risk. The return of the employee to his or her former job status, or the
removal of special protections or limitations, depends upon the
examining physician determining that the employee is no longer at
increased risk of material impairment or that special measures are no
longer needed.
During the period of any form of special protection or removal, the
employer must maintain the worker's earnings, seniority, and other
employment rights and benefits (as though the worker had not been
removed) for a period of up to 18 months or for as long as the job the
employee was removed from lasts if less than 18 months. This economic
protection will maximize meaningful worker participation in the medical
surveillance program, and is appropriate as part of the employer's
overall obligation to provide a safe and healthful workplace. The
provisions of MRP benefits during the employee's removal period may,
however, be conditioned upon participation in medical surveillance.
The lead standard provides for a multiple physician review in cases
where the employee wishes a second opinion concerning potential lead
poisoning or toxicity. If an employee wishes a second opinion, he or she
can make an appointment with a physician of his or her choice. This
second physician will review the findings, recommendations or
determinations of the first physician and conduct any examinations,
consultations or tests deemed necessary in an attempt to make a final
medical determination. If the first and second physicians do not agree
in their assessment they must try to resolve their differences. If they
cannot reach an agreement then they must designate a third physician to
resolve the dispute.
The employer must provide examining and consulting physicians with
the following specific information: A copy of the lead regulations and
all appendices, a description of the employee's duties as related to
exposure, the exposure level or anticipated level to lead and any other
toxic substances (if applicable), a description of personal protective
equipment used, blood lead levels, and all prior written medical
opinions regarding the employee in the employer's possession or control.
The employer must also obtain from the physician and provide the
employee with a written medical opinion containing blood lead levels,
the physicians's opinion as to whether the employee is at risk of
material impairment to health, any recommended protective measures for
the employee if further exposure is permitted, as well as any
recommended limitations upon an employee's use of respirators.
Employers must instruct each physician not to reveal to the employer
in writing or in any other way his or her findings, laboratory results,
or diagnoses which are felt to be unrelated to occupational lead
exposure. They must also instruct each physician to advise the employee
of any occupationally or non-occupationally related medical condition
requiring further treatment or evaluation.
The standard provides for the use of respirators where engineering
and other primary controls are not effective. However, the use of
respirator protection shall not be used in lieu of temporary medical
removal due to elevated blood lead levels or findings that an employee
is at risk of material health impairment. This is based on the numerous
inadequacies of respirators including skin rash where the facepiece
makes contact with the skin, unacceptable stress to breathing in some
workers with underlying cardiopulmonary impairment, difficulty in
providing adequate fit, the tendency for respirators to create
additional hazards by interfering with vision, hearing, and mobility,
and the difficulties of assuring the maximum effectiveness of a
complicated work practice program involving respirators. Respirators do,
however, serve a useful function where engineering and work practice
controls are inadequate by providing supplementary, interim, or short-
term protection, provided they are properly selected for the environment
in which the employee will be working, properly fitted to the employee,
maintained and cleaned periodically, and worn by the employee when
required.
In its interim final standard on occupational exposure to inorganic
lead in the construction industry, OSHA has prohibited prophylactic
chelation. Diagnostic and therapeutic chelation are permitted only under
the supervision of a licensed physician with appropriate medical
monitoring in an acceptable clinical setting. The decision to initiate
chelation therapy must be made on an individual basis and take into
account the severity of symptoms felt to be a result of lead toxicity
along with blood lead levels, ZPP levels, and other laboratory tests as
appropriate. EDTA and penicillamine which are the primary chelating
agents used in the therapy of occupational lead poisoning have
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significant potential side effects and their use must be justified on
the basis of expected benefits to the worker. Unless frank and severe
symptoms are present, therapeutic chelation is not recommended, given
the opportunity to remove a worker from exposure and allow the body to
naturally excrete accumulated lead. As a diagnostic aid, the chelation
mobilization test using CA-EDTA has limited applicability. According to
some investigators, the test can differentiate between lead-induced and
other nephropathies. The test may also provide an estimation of the
mobile fraction of the total body lead burden.
Employers are required to assure that accurate records are
maintained on exposure assessment, including environmental monitoring,
medical surveillance, and medical removal for each employee. Exposure
assessment records must be kept for at least 30 years. Medical
surveillance records must be kept for the duration of employment plus 30
years except in cases where the employment was less than one year. If
duration of employment is less than one year, the employer need not
retain this record beyond the term of employment if the record is
provided to the employee upon termination of employment. Medical removal
records also must be maintained for the duration of employment. All
records required under the standard must be made available upon request
to the Assistant Secretary of Labor for Occupational Safety and Health
and the Director of the National Institute for Occupational Safety and
Health. Employers must also make environmental and biological monitoring
and medical removal records available to affected employees and to
former employees or their authorized employee representatives. Employees
or their specifically designated representatives have access to their
entire medical surveillance records.
In addition, the standard requires that the employer inform all
workers exposed to lead at or above 30 [micro]g/m\3\ of the provisions
of the standard and all its appendices, the purpose and description of
medical surveillance and provisions for medical removal protection if
temporary removal is required. An understanding of the potential health
effects of lead exposure by all exposed employees along with full
understanding of their rights under the lead standard is essential for
an effective monitoring program.
II. Adverse Health Effects of Inorganic Lead
Although the toxicity of lead has been known for 2,000 years, the
knowledge of the complex relationship between lead exposure and human
response is still being refined. Significant research into the toxic
properties of lead continues throughout the world, and it should be
anticipated that our understanding of thresholds of effects and margins
of safety will be improved in future years. The provisions of the lead
standard are founded on two prime medical judgments: First, the
prevention of adverse health effects from exposure to lead throughout a
working lifetime requires that worker blood lead levels be maintained at
or below 40 [micro]g/dl and second, the blood lead levels of workers,
male or female, who intend to parent in the near future should be
maintained below 30 [micro]g/dl to minimize adverse reproductive health
effects to the parents and developing fetus. The adverse effects of lead
on reproduction are being actively researched and OSHA encourages the
physician to remain abreast of recent developments in the area to best
advise pregnant workers or workers planning to conceive children.
The spectrum of health effects caused by lead exposure can be
subdivided into five developmental stages: Normal, physiological changes
of uncertain significance, pathophysiological changes, overt symptoms
(morbidity), and mortality. Within this process there are no sharp
distinctions, but rather a continuum of effects. Boundaries between
categories overlap due to the wide variation of individual responses and
exposures in the working population. OSHA's development of the lead
standard focused on pathophysiological changes as well as later stages
of disease.
1. Heme Synthesis Inhibition. The earliest demonstrated effect of
lead involves its ability to inhibit at least two enzymes of the heme
synthesis pathway at very low blood levels. Inhibition of delta
aminolevulinic acid dehydrase (ALA-D) which catalyzes the conversion of
delta-aminolevulinic acid (ALA) to protoporphyrin is observed at a blood
lead level below 20 [micro]g/dl. At a blood lead level of 40 [micro]g/
dl, more than 20% of the population would have 70% inhibition of ALA-D.
There is an exponential increase in ALA excretion at blood lead levels
greater than 40 [micro]g/dl.
Another enzyme, ferrochelatase, is also inhibited at low blood lead
levels. Inhibition of ferrochelatase leads to increased free erythrocyte
protoporphyrin (FEP) in the blood which can then bind to zinc to yield
zinc protoporphyrin. At a blood lead level of 50 [micro]g/dl or greater,
nearly 100% of the population will have an increase in FEP. There is
also an exponential relationship between blood lead levels greater than
40 [micro]g/dl and the associated ZPP level, which has led to the
development of the ZPP screening test for lead exposure.
While the significance of these effects is subject to debate, it is
OSHA's position that these enzyme disturbances are early stages of a
disease process which may eventually result in the clinical symptoms of
lead poisoning. Whether or not the effects do progress to the later
stages of clinical disease, disruption of these enzyme processes
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over a working lifetime is considered to be a material impairment of
health.
One of the eventual results of lead-induced inhibition of enzymes in
the heme synthesis pathway is anemia which can be asymptomatic if mild
but associated with a wide array of symptoms including dizziness,
fatigue, and tachycardia when more severe. Studies have indicated that
lead levels as low as 50 [micro]g/dl can be associated with a definite
decreased hemoglobin, although most cases of lead-induced anemia, as
well as shortened red-cell survival times, occur at lead levels
exceeding 80 [micro]g/dl. Inhibited hemoglobin synthesis is more common
in chronic cases whereas shortened erythrocyte life span is more common
in acute cases.
In lead-induced anemias, there is usually a reticulocytosis along
with the presence of basophilic stippling, and ringed sideroblasts,
although none of the above are pathognomonic for lead-induced anemia.
2. Neurological Effects. Inorganic lead has been found to have toxic
effects on both the central and peripheral nervous systems. The earliest
stages of lead-induced central nervous system effects first manifest
themselves in the form of behavioral disturbances and central nervous
system symptoms including irritability, restlessness, insomnia and other
sleep disturbances, fatigue, vertigo, headache, poor memory, tremor,
depression, and apathy. With more severe exposure, symptoms can progress
to drowsiness, stupor, hallucinations, delirium, convulsions and coma.
The most severe and acute form of lead poisoning which usually
follows ingestion or inhalation of large amounts of lead is acute
encephalopathy which may arise precipitously with the onset of
intractable seizures, coma, cardiorespiratory arrest, and death within
48 hours.
While there is disagreement about what exposure levels are needed to
produce the earliest symptoms, most experts agree that symptoms
definitely can occur at blood lead levels of 60 [micro]g/dl whole blood
and therefore recommend a 40 [micro]g/dl maximum. The central nervous
system effects frequently are not reversible following discontinued
exposure or chelation therapy and when improvement does occur, it is
almost always only partial.
The peripheral neuropathy resulting from lead exposure
characteristically involves only motor function with minimal sensory
damage and has a marked predilection for the extensor muscles of the
most active extremity. The peripheral neuropathy can occur with varying
degrees of severity. The earliest and mildest form which can be detected
in workers with blood lead levels as low as 50 [micro]g/dl is manifested
by slowing of motor nerve conduction velocity often without clinical
symptoms. With progression of the neuropathy there is development of
painless extensor muscle weakness usually involving the extensor muscles
of the fingers and hand in the most active upper extremity, followed in
severe cases by wrist drop or, much less commonly, foot drop.
In addition to slowing of nerve conduction, electromyographical
studies in patients with blood lead levels greater than 50 [micro]g/dl
have demonstrated a decrease in the number of acting motor unit
potentials, an increase in the duration of motor unit potentials, and
spontaneous pathological activity including fibrillations and
fasciculations. Whether these effects occur at levels of 40 [micro]g/dl
is undetermined.
While the peripheral neuropathies can occasionally be reversed with
therapy, again such recovery is not assured particularly in the more
severe neuropathies and often improvement is only partial. The lack of
reversibility is felt to be due in part to segmental demyelination.
3. Gastrointestinal. Lead may also affect the gastrointestinal
system producing abdominal colic or diffuse abdominal pain,
constipation, obstipation, diarrhea, anorexia, nausea and vomiting. Lead
colic rarely develops at blood lead levels below 80 [micro]g/dl.
4. Renal. Renal toxicity represents one of the most serious health
effects of lead poisoning. In the early stages of disease nuclear
inclusion bodies can frequently be identified in proximal renal tubular
cells. Renal function remains normal and the changes in this stage are
probably reversible. With more advanced disease there is progressive
interstitial fibrosis and impaired renal function. Eventually extensive
interstitial fibrosis ensues with sclerotic glomeruli and dilated and
atrophied proximal tubules; all represent end stage kidney disease.
Azotemia can be progressive, eventually resulting in frank uremia
necessitating dialysis. There is occasionally associated hypertension
and hyperuricemia with or without gout.
Early kidney disease is difficult to detect. The urinalysis is
normal in early lead nephropathy and the blood urea nitrogen and serum
creatinine increase only when two-thirds of kidney function is lost.
Measurement of creatinine clearance can often detect earlier disease as
can other methods of measurement of glomerular filtration rate. An
abnormal Ca-EDTA mobilization test has been used to differentiate
between lead-induced and other nephropathies, but this procedure is not
widely accepted. A form of Fanconi syndrome with aminoaciduria,
glycosuria, and hyperphosphaturia indicating severe injury to the
proximal renal tubules is occasionally seen in children.
5. Reproductive effects. Exposure to lead can have serious effects
on reproductive function in both males and females. In male workers
exposed to lead there can be a decrease in sexual drive, impotence,
decreased ability to produce healthy sperm, and sterility. Malformed
sperm (teratospermia), decreased number of sperm (hypospermia), and
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sperm with decreased motility (asthenospermia) can all occur.
Teratospermia has been noted at mean blood lead levels of 53 [micro]g/dl
and hypospermia and asthenospermia at 41 [micro]g/dl. Furthermore, there
appears to be a dose-response relationship for teratospermia in lead
exposed workers.
Women exposed to lead may experience menstrual disturbances
including dysmenorrhea, menorrhagia and amenorrhea. Following exposure
to lead, women have a higher frequency of sterility, premature births,
spontaneous miscarriages, and stillbirths.
Germ cells can be affected by lead and cause genetic damage in the
egg or sperm cells before conception and result in failure to implant,
miscarriage, stillbirth, or birth defects.
Infants of mothers with lead poisoning have a higher mortality
during the first year and suffer from lowered birth weights, slower
growth, and nervous system disorders.
Lead can pass through the placental barrier and lead levels in the
mother's blood are comparable to concentrations of lead in the umbilical
cord at birth. Transplacental passage becomes detectable at 12-14 weeks
of gestation and increases until birth.
There is little direct data on damage to the fetus from exposure to
lead but it is generally assumed that the fetus and newborn would be at
least as susceptible to neurological damage as young children. Blood
lead levels of 50-60 [micro]g/dl in children can cause significant
neurobehavioral impairments and there is evidence of hyperactivity at
blood levels as low as 25 [micro]g/dl. Given the overall body of
literature concerning the adverse health effects of lead in children,
OSHA feels that the blood lead level in children should be maintained
below 30 [micro]g/dl with a population mean of 15 [micro]g/dl. Blood
lead levels in the fetus and newborn likewise should not exceed 30
[micro]g/dl.
Because of lead's ability to pass through the placental barrier and
also because of the demonstrated adverse effects of lead on reproductive
function in both the male and female as well as the risk of genetic
damage of lead on both the ovum and sperm, OSHA recommends a 30
[micro]g/dl maximum permissible blood lead level in both males and
females who wish to bear children.
6. Other toxic effects. Debate and research continue on the effects
of lead on the human body. Hypertension has frequently been noted in
occupationally exposed individuals although it is difficult to assess
whether this is due to lead's adverse effects on the kidney or if some
other mechanism is involved. Vascular and electrocardiographic changes
have been detected but have not been well characterized. Lead is thought
to impair thyroid function and interfere with the pituitary-adrenal
axis, but again these effects have not been well defined.
III. Medical Evaluation
The most important principle in evaluating a worker for any
occupational disease including lead poisoning is a high index of
suspicion on the part of the examining physician. As discussed in
Section 2, lead can affect numerous organ systems and produce a wide
array of signs and symptoms, most of which are non-specific and subtle
in nature at least in the early stages of disease. Unless serious
concern for lead toxicity is present, many of the early clues to
diagnosis may easily be overlooked.
The crucial initial step in the medical evaluation is recognizing
that a worker's employment can result in exposure to lead. The worker
will frequently be able to define exposures to lead and lead containing
materials but often will not volunteer this information unless
specifically asked. In other situations the worker may not know of any
exposures to lead but the suspicion might be raised on the part of the
physician because of the industry or occupation of the worker. Potential
occupational exposure to lead and its compounds occur in many
occupations in the construction industry, including demolition and
salvaging operations, removal or encapsulation of materials containing
lead, construction, alteration, repair or renovation of structures
containing lead, transportation, disposal, storage or containment of
lead or lead-containing materials on construction sites, and maintenance
operations associated with construction activities.
Once the possibility for lead exposure is raised, the focus can then
be directed toward eliciting information from the medical history,
physical exam, and finally from laboratory data to evaluate the worker
for potential lead toxicity.
A complete and detailed work history is important in the initial
evaluation. A listing of all previous employment with information on job
description, exposure to fumes or dust, known exposures to lead or other
toxic substances, a description of any personal protective equipment
used, and previous medical surveillance should all be included in the
worker's record. Where exposure to lead is suspected, information
concerning on-the-job personal hygiene, smoking or eating habits in work
areas, laundry procedures, and use of any protective clothing or
respiratory protection equipment should be noted. A complete work
history is essential in the medical evaluation of a worker with
suspected lead toxicity, especially when long term effects such as
neurotoxicity and nephrotoxicity are considered.
The medical history is also of fundamental importance and should
include a listing of all past and current medical conditions, current
medications including proprietary drug
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intake, previous surgeries and hospitalizations, allergies, smoking
history, alcohol consumption, and also non-occupational lead exposures
such as hobbies (hunting, riflery). Also known childhood exposures
should be elicited. Any previous history of hematological, neurological,
gastrointestinal, renal, psychological, gynecological, genetic, or
reproductive problems should be specifically noted.
A careful and complete review of systems must be performed to assess
both recognized complaints and subtle or slowly acquired symptoms which
the worker might not appreciate as being significant. The review of
symptoms should include the following:
1. General--weight loss, fatigue, decreased appetite.
2. Head, Eyes, Ears, Nose, Throat (HEENT)--headaches, visual
disturbances or decreased visual acuity, hearing deficits or tinnitus,
pigmentation of the oral mucosa, or metallic taste in mouth.
3. Cardio-pulmonary--shortness of breath, cough, chest pains,
palpitations, or orthopnea.
4. Gastrointestinal--nausea, vomiting, heartburn, abdominal pain,
constipation or diarrhea.
5. Neurologic--irritability, insomnia, weakness (fatigue),
dizziness, loss of memory, confusion, hallucinations, incoordination,
ataxia, decreased strength in hands or feet, disturbances in gait,
difficulty in climbing stairs, or seizures.
6. Hematologic--pallor, easy fatigability, abnormal blood loss,
melena.
7. Reproductive (male and female and spouse where relevant)--history
of infertility, impotence, loss of libido, abnormal menstrual periods,
history of miscarriages, stillbirths, or children with birth defects.
8. Musculo-skeletal--muscle and joint pains.
The physical examination should emphasize the neurological,
gastrointestinal, and cardiovascular systems. The worker's weight and
blood pressure should be recorded and the oral mucosa checked for
pigmentation characteristic of a possible Burtonian or lead line on the
gingiva. It should be noted, however, that the lead line may not be
present even in severe lead poisoning if good oral hygiene is practiced.
The presence of pallor on skin examination may indicate an anemia
which, if severe, might also be associated with a tachycardia. If an
anemia is suspected, an active search for blood loss should be
undertaken including potential blood loss through the gastrointestinal
tract.
A complete neurological examination should include an adequate
mental status evaluation including a search for behavioral and
psychological disturbances, memory testing, evaluation for irritability,
insomnia, hallucinations, and mental clouding. Gait and coordination
should be examined along with close observation for tremor. A detailed
evaluation of peripheral nerve function including careful sensory and
motor function testing is warranted. Strength testing particularly of
extensor muscle groups of all extremities is of fundamental importance.
Cranial nerve evaluation should also be included in the routine
examination.
The abdominal examination should include auscultation for bowel
sounds and abdominal bruits and palpation for organomegaly, masses, and
diffuse abdominal tenderness.
Cardiovascular examination should evaluate possible early signs of
congestive heart failure. Pulmonary status should be addressed
particularly if respirator protection is contemplated.
As part of the medical evaluation, the interim lead standard
requires the following laboratory studies:
1. Blood lead level
2. Hemoglobin and hematocrit determinations, red cell indices, and
examination of the peripheral blood smear to evaluate red blood cell
morphology
3. Blood urea nitrogen
4. Serum creatinine
5. Routine urinalysis with microscopic examination.
6. A zinc protoporphyrin level.
In addition to the above, the physician is authorized to order any
further laboratory or other tests which he or she deems necessary in
accordance with sound medical practice. The evaluation must also include
pregnancy testing or laboratory evaluation of male fertility if
requested by the employee. Additional tests which are probably not
warranted on a routine basis but may be appropriate when blood lead and
ZPP levels are equivocal include delta aminolevulinic acid and
coproporphyrin concentrations in the urine, and dark-field illumination
for detection of basophilic stippling in red blood cells.
If an anemia is detected further studies including a careful
examination of the peripheral smear, reticulocyte count, stool for
occult blood, serum iron, total iron binding capacity, bilirubin, and,
if appropriate, vitamin B12 and folate may be of value in attempting to
identify the cause of the anemia.
If a peripheral neuropathy is suspected, nerve conduction studies
are warranted both for diagnosis and as a basis to monitor any therapy.
If renal disease is questioned, a 24 hour urine collection for
creatinine clearance, protein, and electrolytes may be indicated.
Elevated uric acid levels may result from lead-induced renal disease and
a serum uric acid level might be performed.
An electrocardiogram and chest x-ray may be obtained as deemed
appropriate.
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Sophisticated and highly specialized testing should not be done
routinely and where indicated should be under the direction of a
specialist.
IV. Laboratory Evaluation
The blood lead level at present remains the single most important
test to monitor lead exposure and is the test used in the medical
surveillance program under the lead standard to guide employee medical
removal. The ZPP has several advantages over the blood lead level.
Because of its relatively recent development and the lack of extensive
data concerning its interpretation, the ZPP currently remains an
ancillary test.
This section will discuss the blood lead level and ZPP in detail and
will outline their relative advantages and disadvantages. Other blood
tests currently available to evaluate lead exposure will also be
reviewed.
The blood lead level is a good index of current or recent lead
absorption when there is no anemia present and when the worker has not
taken any chelating agents. However, blood lead levels along with
urinary lead levels do not necessarily indicate the total body burden of
lead and are not adequate measures of past exposure. One reason for this
is that lead has a high affinity for bone and up to 90% of the body's
total lead is deposited there. A very important component of the total
lead body burden is lead in soft tissue (liver, kidney, and brain). This
fraction of the lead body burden, the biologically active lead, is not
entirely reflected by blood lead levels since it is a function of the
dynamics of lead absorption, distribution, deposition in bone and
excretion. Following discontinuation of exposure to lead, the excess
body burden is only slowly mobilized from bone and other relatively
stable body stores and excreted. Consequently, a high blood lead level
may only represent recent heavy exposure to lead without a significant
total body excess and likewise a low blood lead level does not exclude
an elevated total body burden of lead.
Also due to its correlation with recent exposures, the blood lead
level may vary considerably over short time intervals.
To minimize laboratory error and erroneous results due to
contamination, blood specimens must be carefully collected after
thorough cleaning of the skin with appropriate methods using lead-free
blood containers and analyzed by a reliable laboratory. Under the
standard, samples must be analyzed in laboratories which are approved by
OSHA. Analysis is to be made using atomic absorption spectrophotometry,
anodic stripping voltammetry or any method which meets the accuracy
requirements set forth by the standard.
The determination of lead in urine is generally considered a less
reliable monitoring technique than analysis of whole blood primarily due
to individual variability in urinary excretion capacity as well as the
technical difficulty of obtaining accurate 24 hour urine collections. In
addition, workers with renal insufficiency, whether due to lead or some
other cause, may have decreased lead clearance and consequently urine
lead levels may underestimate the true lead burden. Therefore, urine
lead levels should not be used as a routine test.
The zinc protoporphyrin test, unlike the blood lead determination,
measures an adverse metabolic effect of lead and as such is a better
indicator of lead toxicity than the level of blood lead itself. The
level of ZPP reflects lead absorption over the preceding 3 to 4 months,
and therefore is a better indicator of lead body burden. The ZPP
requires more time than the blood lead to read significantly elevated
levels; the return to normal after discontinuing lead exposure is also
slower. Furthermore, the ZPP test is simpler, faster, and less expensive
to perform and no contamination is possible. Many investigators believe
it is the most reliable means of monitoring chronic lead absorption.
Zinc protoporphyrin results from the inhibition of the enzyme
ferrochelatase which catalyzes the insertion of an iron molecule into
the protoporphyrin molecule, which then becomes heme. If iron is not
inserted into the molecule then zinc, having a greater affinity for
protoporphyrin, takes the place of the iron, forming ZPP.
An elevation in the level of circulating ZPP may occur at blood lead
levels as low as 20-30 [micro]g/dl in some workers. Once the blood lead
level has reached 40 [micro]g/dl there is more marked rise in the ZPP
value from its normal range of less than 100 [micro]g/dl100 ml.
Increases in blood lead levels beyond 40 [micro]g/100 g are associated
with exponential increases in ZPP.
Whereas blood lead levels fluctuate over short time spans, ZPP
levels remain relatively stable. ZPP is measured directly in red blood
cells and is present for the cell's entire 120 day life-span. Therefore,
the ZPP level in blood reflects the average ZPP production over the
previous 3-4 months and consequently the average lead exposure during
that time interval.
It is recommended that a hematocrit be determined whenever a
confirmed ZPP of 50 [micro]g/100 ml whole blood is obtained to rule out
a significant underlying anemia. If the ZPP is in excess of 100
[micro]g/100 ml and not associated with abnormal elevations in blood
lead levels, the laboratory should be checked to be sure that blood
leads were determined using atomic absorption spectrophotometry anodic
stripping voltammetry, or any method which meets the accuracy
requirements set forth by the standard by an OSHA approved laboratory
which is experienced in lead level determinations. Repeat periodic blood
lead
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studies should be obtained in all individuals with elevated ZPP levels
to be certain that an associated elevated blood lead level has not been
missed due to transient fluctuations in blood leads.
ZPP has a characteristic fluorescence spectrum with a peak at 594 nm
which is detectable with a hematofluorimeter. The hematofluorimeter is
accurate and portable and can provide on-site, instantaneous results for
workers who can be frequently tested via a finger prick.
However, careful attention must be given to calibration and quality
control procedures. Limited data on blood lead-ZPP correlations and the
ZPP levels which are associated with the adverse health effects
discussed in Section 2 are the major limitations of the test. Also it is
difficult to correlate ZPP levels with environmental exposure and there
is some variation of response with age and sex. Nevertheless, the ZPP
promises to be an important diagnostic test for the early detection of
lead toxicity and its value will increase as more data is collected
regarding its relationship to other manifestations of lead poisoning.
Levels of delta-aminolevulinic acid (ALA) in the urine are also used
as a measure of lead exposure. Increasing concentrations of ALA are
believed to result from the inhibition of the enzyme delta-
aminolevulinic acid dehydrase (ALA-D). Although the test is relatively
easy to perform, inexpensive, and rapid, the disadvantages include
variability in results, the necessity to collect a complete 24 hour
urine sample which has a specific gravity greater than 1.010, and also
the fact that ALA decomposes in the presence of light.
The pattern of porphyrin excretion in the urine can also be helpful
in identifying lead intoxication. With lead poisoning, the urine
concentrations of coproporphyrins I and II, porphobilinogen and
uroporphyrin I rise. The most important increase, however, is that of
coproporphyrin III; levels may exceed 5,000 [micro]g/l in the urine in
lead poisoned individuals, but its correlation with blood lead levels
and ZPP are not as good as those of ALA. Increases in urinary porphyrins
are not diagnostic of lead toxicity and may be seen in porphyria, some
liver diseases, and in patients with high reticulocyte counts.
Summary. The Occupational Safety and Health Administration's interim
standard for inorganic lead in the construction industry places
significant emphasis on the medical surveillance of all workers exposed
to levels of inorganic lead above 30 [micro]g/m\3\ TWA. The physician
has a fundamental role in this surveillance program, and in the
operation of the medical removal protection program.
Even with adequate worker education on the adverse health effects of
lead and appropriate training in work practices, personal hygiene and
other control measures, the physician has a primary responsibility for
evaluating potential lead toxicity in the worker. It is only through a
careful and detailed medical and work history, a complete physical
examination and appropriate laboratory testing that an accurate
assessment can be made. Many of the adverse health effects of lead
toxicity are either irreversible or only partially reversible and
therefore early detection of disease is very important.
This document outlines the medical monitoring program as defined by
the occupational safety and health standard for inorganic lead. It
reviews the adverse health effects of lead poisoning and describes the
important elements of the history and physical examinations as they
relate to these adverse effects. Finally, the appropriate laboratory
testing for evaluating lead exposure and toxicity is presented.
It is hoped that this review and discussion will give the physician
a better understanding of the OSHA standard with the ultimate goal of
protecting the health and well-being of the worker exposed to lead under
his or her care.
[58 FR 26627, May 4, 1993, as amended at 58 FR 34218, June 24, 1993; 61
FR 5510, Feb. 13, 1996; 63 FR 1296, Jan. 8, 1998; 70 FR 1143, Jan. 5,
2005; 71 FR 16674, Apr. 3, 2006; 71 FR 50191, Aug. 24, 2006]
