§1910.1047 Ethylene oxide

[Code of Federal Regulations]
[Title 29, Volume 6]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 29CFR1910.1047]

[Page 336-356]

TITLE 29--LABOR

CHAPTER XVII--OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT

OF LABOR

PART 1910_OCCUPATIONAL SAFETY AND HEALTH STANDARDS (CONTINUED)--Table of Contents

Subpart Z_Toxic and Hazardous Substances

Sec. 1910.1047 Ethylene oxide.

(a) Scope and application. (1) This section applies to all

occupational exposures to ethylene oxide (EtO), Chemical Abstracts

Service Registry No. 75-21-8, except as provided in paragraph (a)(2) of

this section.

(2) This section does not apply to the processing, use, or handling

of products containing EtO where objective data are reasonably relied

upon that demonstrate that the product is not capable of releasing EtO

in airborne concentrations at or above the action level, and may not

reasonably be foreseen to release EtO in excess of the excursion limit,

under the expected conditions of processing, use, or handling that will

cause the greatest possible release.

(3) Where products containing EtO are exempted under paragraph

(a)(2) of this section, the employer shall maintain records of the

objective data supporting that exemption and the basis for the

employer's reliance on the data, as provided in paragraph (k)(1) of this

section.

(b) Definitions: For the purpose of this section, the following

definitions shall apply:

Action level means a concentration of airborne EtO of 0.5 ppm

calculated as an eight (8)-hour time-weighted average.

Assistant Secretary means the Assistant Secretary of Labor for

Occupational Safety and Health, U.S. Department of Labor, or designee.

Authorized person means any person specifically authorized by the

employer whose duties require the person to enter a regulated area, or

any person entering such an area as a designated representative of

employees for the purpose of exercising the right to observe monitoring

and measuring procedures under paragraph (l) of this section, or any

other person authorized by the Act or regulations issued under the Act.

Director means the Director of the National Institute for

Occupational Safety and Health, U.S. Department of Health and Human

Services, or designee.

Emergency means any occurrence such as, but not limited to,

equipment failure, rupture of containers, or failure of control

equipment that is likely to or does result in an unexpected significant

release of EtO.

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Employee exposure means exposure to airborne EtO which would occur

if the employee were not using respiratory protective equipment.

Ethylene oxide or EtO means the three-membered ring organic compound

with chemical formula C<INF>2</INF> H<INF>4</INF> O.

(TWA). The employer shall ensure that no employee is exposed to an

airborne concentration of EtO in excess of one (1) part EtO per million

parts of air (1 ppm) as an 8-hour time-weighted average (8-hour TWA).

(2) Excursion limit. The employer shall ensure that no employee is

exposed to an airborne concentration of EtO in excess of 5 parts of EtO

per million parts of air (5 ppm) as averaged over a sampling period of

fifteen (15) minutes.

(d) Exposure monitoring--(1) General. (i) Determinations of employee

exposure shall be made from breathing zone air samples that are

representative of the 8-hour TWA and 15-minute short-term exposures of

each employee.

(ii) Representative 8-hour TWA employee exposure shall be determined

on the basis of one or more samples representing full-shift exposure for

each shift for each job classification in each work area. Representative

15-minute short-term employee exposures shall be determined on the basis

of one or more samples representing 15-minute exposures associated with

operations that are most likely to produce exposures above the excursion

limit for each shift for each job classification in each work area.

(iii) Where the employer can document that exposure levels are

equivalent for similar operations in different work shifts, the employer

need only determine representative employee exposure for that operation

during one shift.

(2) Initial monitoring. (i) Each employer who has a workplace or

work operation covered by this standard, except as provided for in

paragraph (a)(2) or (d)(2)(ii) of this section, shall perform initial

monitoring to determine accurately the airborne concentrations of EtO to

which employees may be exposed.

(ii) Where the employer has monitored after June 15, 1983 and the

monitoring satisfies all other requirements of this section, the

employer may rely on such earlier monitoring results to satisfy the

requirements of paragraph (d)(2)(i) of this section.

(iii) Where the employer has previously monitored for the excursion

limit and the monitoring satisfies all other requirements of this

sections, the employer may rely on such earlier monitoring results to

satisfy the requirements of paragraph (d)(2)(i) of this section.

(3) Monitoring frequency (periodic monitoring). (i) If the

monitoring required by paragraph (d)(2) of this section reveals employee

exposure at or above the action level but at or below the 8-hour TWA,

the employer shall repeat such monitoring for each such employee at

least every 6 months.

(ii) If the monitoring required by paragraph (d)(2)(i) of this

section reveals employee exposure above the 8-hour TWA, the employer

shall repeat such monitoring for each such employee at least every 3

months.

(iii) The employer may alter the monitoring schedule from quarterly

to semiannually for any employee for whom two consecutive measurements

taken at least 7 days apart indicate that the employee's exposure has

decreased to or below the 8-hour TWA.

(iv) If the monitoring required by paragraph (d)(2)(i) of this

section reveals employee exposure above the 15 minute excursion limit,

the employer shall repeat such monitoring for each such employee at

least every 3 months, and more often as necessary to evaluate exposure

the employee's short-term exposures.

(4) Termination of monitoring. (i) If the initial monitoring

required by paragraph (d)(2)(i) of this section reveals employee

exposure to be below the action level, the employer may discontinue TWA

monitoring for those employees whose exposures are represented by the

initial monitoring.

(ii) If the periodic monitoring required by paragraph (d)(3) of this

section reveals that employee exposures, as indicated by at least two

consecutive measurements taken at least 7 days apart, are below the

action level, the employer may discontinue TWA monitoring for those

employees whose

[[Page 338]]

exposures are represented by such monitoring.

(iii) If the initial monitoring required by paragraph (d)(2)(1) of

this section reveals employee exposure to be at or below the excursion

limit, the employer may discontinue excursion limit monitoring for those

employees whose exposures are represented by the initial monitoring.

(iv) If the periodic monitoring required by paragraph (d)(3) of this

section reveals that employee exposures, as indicated by at least two

consecutive measurements taken at least 7 days apart, are at or below

the excursion limit, the employer may discontinue excursion limit

monitoring for those employees whose exposures are represented by such

monitoring.

(5) Additional monitoring. Notwithstanding the provisions of

paragraph (d)(4) of this section, the employer shall institute the

exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of

this section whenever there has been a change in the production,

process, control equipment, personnel or work practices that may result

in new or additional exposures to EtO or when the employer has any

reason to suspect that a change may result in new or additional

exposures.

(6) Accuracy of monitoring. (i) Monitoring shall be accurate, to a

confidence level of 95 percent, to within plus or minus 25 percent for

airborne concentrations of EtO at the 1 ppm TWA and to within plus or

minus 35 percent for airborne concentrations of EtO at the action level

of 0.5 ppm.

(ii) Monitoring shall be accurate, to a confidence level of 95

percent, to within plus or minus 35 percent for airborne concentrations

of EtO at the excursion limit.

(7) Employee notification of monitoring results. (i) The employer

must, within 15 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) The written notification required by paragraph (d)(7)(i) of

this section shall contain the corrective action being taken by the

employer to reduce employee exposure to or below the TWA and/or

excursion limit, wherever monitoring results indicated that the TWA and/

or excursion limit has been exceeded.

(e) Regulated areas. (1) The employer shall establish a regulated

area wherever occupational exposure to airborne concentrations of EtO

may exceed the TWA or wherever the EtO concentration exceeds or can

reasonably be expected to exceed the excursion limit.

(2) Access to regulated areas shall be limited to authorized

persons.

(3) Regulated areas shall be demarcated in any manner that minimizes

the number of employees within the regulated area.

(f) Methods of compliance--(1) Engineering controls and work

practices. (i) The employer shall institute engineering controls and

work practices to reduce and maintain employee exposure to or below the

TWA and to or below the excursion limit, except to the extent that such

controls are not feasible.

(ii) Wherever the feasible engineering controls and work practices

that can be instituted are not sufficient to reduce employee exposure to

or below the TWA and to or below the excursion limit, the employer shall

use them to reduce employee exposure to the lowest levels achievable by

these controls and shall supplement them by the use of respiratory

protection that complies with the requirements of paragraph (g) of this

section.

(iii) Engineering controls are generally infeasible for the

following operations: collection of quality assurance sampling from

sterilized materials removal of biological indicators from sterilized

materials: loading and unloading of tank cars; changing of ethylene

oxide tanks on sterilizers; and vessel cleaning. For these operations,

engineering controls are required only where the Assistant Secretary

demonstrates that such controls are feasible.

(2) Compliance program. (i) Where the TWA or excursion limit is

exceeded, the employer shall establish and implement a written program

to reduce exposure to or below the TWA and to or below the excursion

limit by means of

[[Page 339]]

engineering and work practice controls, as required by paragraph (f)(1)

of this section, and by the use of respiratory protection where required

or permitted under this section.

(ii) The compliance program shall include a schedule for periodic

leak detection surveys and a written plan for emergency situations, as

specified in paragraph (h)(i) of this section.

(iii) Written plans for a program required in paragraph (f)(2) shall

be developed and furnished upon request for examination and copying to

the Assistant Secretary, the Director, affected employees and designated

employee representatives. Such plans shall be reviewed at least every 12

months, and shall be updated as necessary to reflect significant changes

in the status of the employer's compliance program.

(iv) The employer shall not implement a schedule of employee

rotation as a means of compliance with the TWA or excursion limit.

(g) Respiratory protection and personal protective equipment--(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 necessary to install or implement feasible engineering

and work-practice controls.

(ii) Work operations, such as maintenance and repair activities and

vessel cleaning, for which engineering and work-practice controls are

not feasible.

(iii) Work operations for which feasible engineering and work-

practice controls are not yet sufficient to reduce employee exposure to

or below the TWA.

(iv) Emergencies.

(2) Respirator program. 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).

(3) Respirator selection. Employers must:

(i) Select, and provide to employees, the appropriate respirators

specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134; however,

employers must not select or use half masks of any type because EtO may

cause eye irritation or injury.

(ii) Equip each air-purifying, full facepiece respirator with a

front-or back-mounted canister approved for protection against ethylene

oxide.

(iii) For escape, provide employees with any respirator permitted

for use under paragraphs (g)(3)(i) and (ii) of this standard.

(4) Protective clothing and equipment. When employees could have eye

or skin contact with EtO or EtO solutions, the employer must select and

provide, at no cost to the employee, appropriate protective clothing or

other equipment in accordance with 29 CFR 1910.132 and 1910.133 to

protect any area of the employee's body that may come in contact with

the EtO or EtO solution, and must ensure that the employee wears the

protective clothing and equipment provided.

(h) Emergency situations--(1) Written plan. (i) A written plan for

emergency situations shall be developed for each workplace where there

is a possibility of an emergency. Appropriate portions of the plan shall

be implemented in the event of an emergency.

(ii) The plan shall specifically provide that employees engaged in

correcting emergency conditions shall be equipped with respiratory

protection as required by paragraph (g) of this section until the

emergency is abated.

(iii) The plan shall include the elements prescribed in 29 CFR

1910.38 and 29 CFR 1910.39, ``Emergency action plans'' and ``Fire

prevention plans,'' respectively.

(2) Alerting employees. Where there is the possibility of employee

exposure to EtO due to an emergency, means shall be developed to alert

potentially affected employees of such occurrences promptly. Affected

employees shall be immediately evacuated from the area in the event that

an emergency occurs.

(i) Medical Surveillance--(1) General--(i) Employees covered. (A)

The employer shall institute a medical surveillance program for all

employees who are or may be exposed to EtO at or above the action level,

without regard to the use of respirators, for at least 30 days a year.

(B) The employer shall make available medical examinations and

consultations to all employees who have

[[Page 340]]

been exposed to EtO in an emergency situation.

(ii) Examination by a physician. The employer shall ensure that all

medical examinations and procedures are performed by or under the

supervision of a licensed physician, and are provided without cost to

the employee, without loss of pay, and at a reasonable time and place.

(2) Medical examinations and consultations--(i) Frequency. The

employer shall make available medical examinations and consultations to

each employee covered under paragraph (i)(1)(i) of this section on the

following schedules:

(A) Prior to assignment of the employee to an area where exposure

may be at or above the action level for at least 30 days a year.

(B) At least annually each employee exposed at or above the action

level for at least 30 days in the past year.

exposure to EtO is not at or above the action level for at least 30 days

a year.

(D) As medically appropriate for any employee exposed during an

emergency.

(E) As soon as possible, upon notification by an employee either (1)

that the employee has developed signs or symptoms indicating possible

overexposure to EtO, or (2) that the employee desires medical advice

concerning the effects of current or past exposure to EtO on the

employee's ability to produce a healthy child.

(F) If the examining physician determines that any of the

examinations should be provided more frequently than specified, the

employer shall provide such examinations to affected employees at the

frequencies recommended by the physician.

(ii) Content. (A) Medical examinations made available pursuant to

paragraphs (i)(2)(i)(A)-(D) of this section shall include:

(1) A medical and work history with special emphasis directed to

symptoms related to the pulmonary, hematologic, neurologic, and

reproductive systems and to the eyes and skin.

(2) A physical examination with particular emphasis given to the

pulmonary, hematologic, neurologic, and reproductive systems and to the

eyes and skin.

(3) A complete blood count to include at least a white cell count

(including differential cell count), red cell count, hematocrit, and

hemoglobin.

(4) Any laboratory or other test which the examining physician deems

necessary by sound medical practice.

(B) The content of medical examinations or consultation made

available pursuant to paragraph (i)(2)(i)(E) of this section shall be

determined by the examining physician, and shall include pregnancy

testing or laboratory evaluation of fertility, if requested by the

employee and deemed appropriate by the physician.

(3) Information provided to the physician. The employer shall

provide the following information to the examining physician:

(i) A copy of this standard and Appendices A, B, and C.

(ii) A description of the affected employee's duties as they relate

to the employee's exposure.

(iii) The employee's representative exposure level or anticipated

exposure level.

(iv) A description of any personal protective and respiratory

equipment used or to be used.

(v) Information from previous medical examinations of the affected

employee that is not otherwise available to the examining physician.

(4) Physician's written opinion. (i) The employer shall obtain a

written opinion from the examining physician. This written opinion shall

contain the results of the medical examination and shall include:

(A) The physician's opinion as to whether the employee has any

detected medical conditions that would place the employee at an

increased risk of material health impairment from exposure to EtO;

(B) Any recommended limitations on the employee or upon the use of

personal protective equipment such as clothing or respirators; and

of the results of the medical examination and of any medical conditions

resulting from EtO exposure that require further explanation or

treatment.

[[Page 341]]

(ii) The employer shall instruct the physician not to reveal in the

written opinion given to the employer specific findings or diagnoses

unrelated to occupational exposure to EtO.

(iii) The employer shall provide a copy of the physician's written

opinion to the affected employee within 15 days from its receipt.

(j) Communication of EtO hazards to employees--(1) Signs and labels.

(i) The employer shall post and maintain legible signs demarcating

regulated areas and entrances or accessways to regulated areas that bear

the following legend:

DANGER

ETHYLENE OXIDE

CANCER HAZARD AND REPRODUCTIVE HAZARD

AUTHORIZED PERSONNEL ONLY

RESPIRATORS AND PROTECTIVE CLOTHING MAY BE REQUIRED

TO BE WORN IN THIS AREA

(ii) The employer shall ensure that precautionary labels are affixed

to all containers of EtO whose contents are capable of causing employee

exposure at or above the action level or whose contents may reasonably

be foreseen to cause employee exposure above the excursion limit, and

that the labels remain affixed when the containers of EtO leave the

workplace. For the purpose of this paragraph, reaction vessels, storage

tanks, and pipes or piping systems are not considered to be containers.

The labels shall comply with the requirements of 29 CFR 1910.1200(f) of

OSHA's Hazard Communication standard, and shall include the following

legend:

(A) DANGER

CONTAINS ETHYLENE OXIDE

CANCER HAZARD AND REPRODUCTIVE HAZARD;

and

(B) A warning statement against breathing airborne concentrations of

EtO.

(iii) The labeling requirements under this section do not apply

where EtO is used as a pesticide, as such term is defined in the Federal

Insecticide. Fungicide, and Rodenticide Act (7 U.S.C. 136 et seq.), when

it is labeled pursuant to that Act and regulations issued under that Act

by the Environmental Protection Agency.

(2) Material safety data sheets. Employers who are manufacturers or

importers of EtO shall comply with the requirements regarding

development of material safety data sheets as specified in 29 CFR

1910.1200(g) of OSHA's Hazard Communication standard.

(3) Information and training. (i) The employer shall provide

employees who are potentially exposed to EtO at or above the action

level or above the excursion limit with information and training on EtO

at the time of initial assignment and at least annually thereafter.

(ii) Employees shall be informed of the following:

(A) The requirements of this section with an explanation of its

contents, including Appendices A and B;

(B) Any operations in their work area where EtO is present;

(D) The medical surveillance program required by paragraph (i) of

this section with an explanation of the information in Appendix C.

(iii) Employee training shall include at least:

(A) Methods and observations that may be used to detect the presence

or release of EtO in the work area (such as monitoring conducted by the

employer, continuous monitoring devices, etc.);

(B) The physical and health hazards of EtO;

hazards associated with EtO exposure, including specific procedures the

employer has implemented to protect employees from exposure to EtO, such

as work practices, emergency procedures, and personal protective

equipment to be used; and

(D) The details of the hazard communication program developed by the

employer, including an explanation of the labeling system and how

employees can obtain and use the appropriate hazard information.

(k) Recordkeeping--(1) Objective data for exempted operations. (i)

Where the processing, use, or handling of products

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made from or containing EtO are exempted from other requirements of this

section under paragraph (a)(2) of this section, or where objective data

have been relied on in lieu of initial monitoring under paragraph

(d)(2)(ii) of this section, the employer shall establish and maintain an

accurate record of objective data reasonably relied upon in support of

the exemption.

(ii) This record shall include at least the following information:

(A) The product qualifying for exemption;

(B) The source of the objective data;

material for the release of EtO;

(D) A description of the operation exempted and how the data support

the exemption; and

(E) Other data relevant to the operations, materials, processing, or

employee exposures covered by the exemption.

(iii) The employer shall maintain this record for the duration of

the employer's reliance upon such objective data.

(2) Exposure measurements. (i) The employer shall keep an accurate

record of all measurements taken to monitor employee exposure to EtO as

prescribed in paragraph (d) of this section.

(ii) This record shall include at least the following information:

(A) The date of measurement;

(B) The operation involving exposure to EtO which is being

monitored;

accuracy;

(D) Number, duration, and results of samples taken;

(E) Type of protective devices worn, if any; and

(F) Name, social security number and exposure of the employees whose

exposures are represented.

(iii) The employer shall maintain this record for at least thirty

(30) years, in accordance with 29 CFR 1910.1020.

(3) Medical surveillance. (i) The employer shall establish and

maintain an accurate record for each employee subject to medical

surveillance by paragraph (i)(1)(i) of this section, in accordance with

29 CFR 1910.1020.

(ii) The record shall include at least the following information:

(A) The name and social security number of the employee;

(B) Physicians' written opinions;

(D) A copy of the information provided to the physician as required

by paragraph (i)(3) of this section.

(iii) The employer shall ensure that this record is maintained for

the duration of employment plus thirty (30) years, in accordance with 29

CFR 1910.1020.

(4) Availability. (i) The employer, upon written request, shall make

all records required to be maintained by this section available to the

Assistant Secretary and the Director for examination and copying.

(ii) The employer, upon request, shall make any exemption and

exposure records required by paragraphs (k) (1) and (2) of this section

available for examination and copying to affected employees, former

employees, designated representatives and the Assistant Secretary, in

accordance with 29 CFR 1910.1020 (a) through (e) and (g) through (i).

(iii) The employer, upon request, shall make employee medical

records required by paragraph (k)(3) of this section available for

examination and copying to the subject employee, anyone having the

specific written consent of the subject employee, and the Assistant

Secretary, in accordance with 29 CFR 1910.1020.

(5) Transfer of records. (i) The employer shall comply with the

requirements concerning transfer of records set forth in 29 CFR

1910.1020(h).

(ii) Whenever the employer ceases to do business and there is no

successor employer to receive and retain the records for the prescribed

period, the employer shall notify the Director at least 90 days prior to

disposal and transmit them to the Director.

(l) 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 EtO conducted in accordance with paragraph (d) of this

section.

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(2) Observation procedures. When observation of the monitoring of

employee exposure to EtO requires entry into an area where the use of

protective clothing or equipment is required, the observer shall be

provided with and be required to use such clothing and equipment and

shall comply with all other applicable safety and health procedures.

(m) [Reserved]

(n) Appendices. The information contained in the appendices is not

intended by itself to create any additional obligations not otherwise

imposed or to detract from any existing obligation.

Appendix A to Sec. 1910.1047--Substance Safety Data Sheet for Ethylene

Oxide (Non-Mandatory)

i. Substance Identification

A. Substance: Ethylene oxide (C<INF>2</INF> H<INF>4</INF> O).

B. Synonyms: dihydrooxirene, dimethylene oxide, EO, 1,2-epoxyethane,

EtO, ETO, oxacyclopropane, oxane, oxidoethane, alpha/beta-oxidoethane,

oxiran, oxirane.

C. Ethylene oxide can be found as a liquid or vapor.

D. EtO is used in the manufacture of ethylene glycol, surfactants,

ethanolamines, glycol ethers, and other organic chemicals. EtO is also

used as a sterilant and fumigant.

E. Appearance and odor: Colorless liquid below 10.7 [deg]C (51.3

[deg]F) or colorless gas with ether-like odor detected at approximately

700 parts EtO per million parts of air (700 ppm).

F. Permissible Exposure: Exposure may not exceed 1 part EtO per

million parts of air averaged over the 8-hour workday.

ii. Health Hazard Data

A. Ethylene oxide can cause bodily harm if you inhale the vapor, if

it comes into contact with your eyes or skin, or if you swallow it.

B. Effects of overexposure:

1. Ethylene oxide in liquid form can cause eye irritation and injury

to the cornea, frostbite, and severe irritation and blistering of the

skin upon prolonged or confined contact. Ingestion of EtO can cause

gastric irritation and liver injury. Acute effects from inhalation of

EtO vapors include respiratory irritation and lung injury, headache,

nausea, vomiting, diarrhea, shortness of breath, and cyaonosis (blue or

purple coloring of skin). Exposure has also been associated with the

occurrence of cancer, reproductive effects, mutagenic changes,

neurotoxicity, and sensitization.

1. EtO has been shown to cause cancer in laboratory animals and has

been associated with higher incidences of cancer in humans. Adverse

reproductive effects and chromosome damage may also occur from EtO

exposure.

a. Reporting signs and symptoms: You should inform your employer if

you develop any signs or symptoms and suspect that they are caused by

exposure to EtO.

iii. Emergency First Aid Procedures

A. Eye exposure: If EtO gets into your eyes, wash your eyes

immediately with large amounts of water, lifting the lower and upper

eyelids. Get medical attention immediately. Contact lenses should not be

worn when working with this chemical.

B. Skin exposure: If EtO gets on your skin, immediately wash the

contaminated skin with water. If EtO soaks through your clothing,

especially your shoes, remove the clothing immediately and wash the skin

with water using an emergency deluge shower. Get medical attention

immediately. Thoroughly wash contaminated clothing before reusing.

Contaminated leather shoes or other leather articles should not be

reused and should be discarded.

C. Inhalation: If large amounts of EtO are inhaled, the exposed

person must be moved to fresh air at once. If breathing has stopped,

perform cardiopulmonary resuscitation. Keep the affected person warm and

at rest. Get medical attention immediately.

D. Swallowing: When EtO has been swallowed, give the person large

quantities of water immediately. After the water has been swallowed, try

to get the person to vomit by having him or her touch the back of the

throat with his or her finger. Do not make an unconscious person vomit.

Get medical attention immediately.

E. Rescue: Move the affected person from the hazardous exposure. If

the exposed person has been overcome, attempt rescue only after

notifying at least one other person of the emergency and putting into

effect established emergency procedures. Do not become a casualty

yourself. Understand your emergency rescue procedures and know the

location of the emergency equipment before the need arises.

iv. Respirators and Protective Clothing

A. Respirators. You may be required to wear a respirator for

nonroutine activities, in emergencies, while your employer is in the

process of reducing EtO exposures through engineering controls, and in

areas where engineering controls are not feasible. As of the effective

date of this standard, only air-supplied, positive-pressure, full-

facepiece respirators are approved for protection against EtO. If air-

purifying respirators are worn in the future, they must have a label

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issued by the National Institute for Occupational Safety and Health

under the provisions of 42 CFR part 84 stating that the respirators have

been approved for use with ethylene oxide. For effective protection,

respirators must fit your face and head snugly. Respirators must not be

loosened or removed in work situations where their use is required.

EtO does not have a detectable odor except at levels well above the

permissible exposure limits. If you can smell EtO while wearing a

respirator, proceed immediately to fresh air. If you experience

difficulty breathing while wearing a respirator, tell your employer.

B. Protective clothing: You may be required to wear impermeable

clothing, gloves, a face shield, or other appropriate protective

clothing to prevent skin contact with liquid EtO or EtO-containing

solutions. Where protective clothing is required, your employer must

provide clean garments to you as necessary to assure that the clothing

protects you adequately.

Replace or repair protective clothing that has become torn or

otherwise damaged.

EtO must never be allowed to remain on the skin. Clothing and shoes

which are not impermeable to EtO should not be allowed to become

contaminated with EtO, and if they do, the clothing should be promptly

removed and decontaminated. Contaminated leather shoes should be

discarded. Once EtO penetrates shoes or other leather articles, they

should not be worn again.

C. Eye protection: You must wear splashproof safety goggles in areas

where liquid EtO or EtO-containing solutions may contact your eyes. In

addition, contact lenses should not be worn in areas where eye contact

with EtO can occur.

v. Precautions for Safe Use, Handling, and Storage

A. EtO is a flammable liquid, and its vapors can easily form

explosive mixtures in air.

B. EtO must be stored in tighly closed containers in a cool, well-

ventilated area, away from heat, sparks, flames, strong oxidizers,

alkalines, and acids, strong bases, acetylide-forming metals such as

cooper, silver, mercury and their alloys.

C. Sources of ignition such as smoking material, open flames and

some electrical devices are prohibited wherever EtO is handled, used, or

stored in a manner that could create a potential fire or explosion

hazard.

D. You should use non-sparking tools when opening or closing metal

containers of EtO, and containers must be bonded and grounded in the

rare instances in which liquid EtO is poured or transferred.

E. Impermeable clothing wet with liquid EtO or EtO-containing

solutions may be easily ignited. If your are wearing impermeable

clothing and are splashed with liquid EtO or EtO-containing solution,

you should immediately remove the clothing while under an emergency

deluge shower.

F. If your skin comes into contact with liquid EtO or EtO-containing

solutions, you should immediately remove the EtO using an emergency

deluge shower.

G. You should not keep food, beverages, or smoking materials in

regulated areas where employee exposures are above the permissible

exposure limits.

H. Fire extinguishers and emergency deluge showers for quick

drenching should be readily available, and you should know where they

are and how to operate them.

I. Ask your supervisor where EtO is used in your work area and for

any additional plant safety and health rules.

vi. Access to Information

A. Each year, your employer is required to inform you of the

information contained in this standard and appendices for EtO. In

addition, your employer must instruct you in the proper work practices

for using EtO emergency procedures, and the correct use of protective

equipment.

B. Your employer is required to determine whether you are being

exposed to EtO. You or your representative has the right to observe

employee measurements and to record the results obtained. Your employer

is required to inform you of your exposure. If your employer determine

that you are being overexposed, he or she is required to inform you of

the actions which are being taken to reduce your exposure to within

permissible exposure limits.

C. Your employer is required to keep records of your exposures and

medical examinations. These exposure records must be kept by the

employer for at least thirty (30) years. Medical records must be kept

for the period of your employment plus thirty (30) years.

D. Your employer is required to release your exposure and medical

records to your physician or designated representative upon your written

request.

vii. Sterilant Use of Eto in Hospitals and Health Care Facilities

This section of Appendix A, for informational purposes, sets forth

EPA's recommendations for modifications in workplace design and practice

in hospitals and health care facilities for which the Environmental

Protection Agency has registered EtO for uses as a sterilant or fumigant

under the Federal Insecticide, Funigicide, and Rodenticide Act, 7 U.S.C.

136 et seq. These new recommendations, published in the Federal Register

by EPA at 49 FR 15268, as modified in today's Register, are intended to

help reduce the exposure of hospital and health care workers to EtO to 1

ppm. EPA's

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recommended workplace design and workplace practice are as follows:

1. Workplace Design

a. Installation of gas line hand valves. Hand valves must be

installed on the gas supply line at the connection to the supply

cylinders to minimize leakage during cylinder change.

b. Installation of capture boxes. Sterilizer operations result in a

gas/water discharge at the completion of the process. This discharge is

routinely piped to a floor drain which is generally located in an

equipment or an adjacent room. When the floor drain is not in the same

room as the sterilizer and workers are not normally present, all that is

necessary is that the room be well ventilated.

The installation of a ``capture box'' will be required for those

work place layouts where the floor drain is located in the same room as

the sterilizer or in a room where workers are normally present. A

``capture box'' is a piece of equipment that totally encloses the floor

drain where the discharge from the sterilizer is pumped. The ``capture

box'' is to be vented directly to a non-recirculating or dedicated

ventilation system. Sufficient air intake should be allowed at the

bottom of the box to handle the volume of air that is ventilated from

the top of the box. The ``capture box'' can be made of metal, plastic,

wood or other equivalent material. The box is intended to reduce levels

of EtO discharged into the work room atmosphere. The use of a ``capture

box'' is not required if: (1) The vacuum pump discharge floor drain is

located in a well ventilated equipment or other room where workers are

not normally present or (2) the water sealed vacuum pump discharges

directly to a closed sealed sewer line (check local plumbing codes).

If it is impractical to install a vented ``capture box'' and a well

ventilated equipment or other room is not feasible, a box that can be

sealed over the floor drain may be used if: (1) The floor drain is

located in a room where workers are not normally present and EtO cannot

leak into an occupied area, and (2) the sterilizer in use is less than

12 cubic feet in capacity (check local plumbing codes).

c. Ventilation of aeration units i. Existing aeration units.

Existing units must be vented to a non-recirculating or dedicated system

or vented to an equipment or other room where workers are not normally

present and which is well ventilated. Aerator units must be positioned

as close as possible to the sterilizer to minimize the exposure from the

off-gassing of sterilized items.

ii. Installation of new aerator units (where none exist). New

aerator units must be vented as described above for existing aerators.

Aerators must be in place by July 1, 1986.

d. Ventilation during cylinder change. Workers may be exposed to

short but relatively high levels of EtO during the change of gas

cylinders. To reduce exposure from this route, users must select one of

three alternatives designed to draw off gas that may be released when

the line from the sterilizer to the cylinder is disconnected:

i. Location of cylinders in a well ventilated equipment room or

other room where workers are not normally present.

ii. Installation of a flexible hose (at least 4<gr-thn-eq> in

diameter) to a non-recirculating or dedicated ventilation system and

located in the area of cylinder change in such a way that the hose can

be positioned at the point where the sterilizer gas line is disconnected

from the cylinder.

iii. Installation of a hood that is part of a non-recirculating or

dedicated system and positioned no more than one foot above the point

where the change of cylinders takes place.

e. Ventilation of sterilizer door area. One of the major sources of

exposure to EtO occurs when the sterilizer door is opened following the

completion of the sterilization process. In order to reduce this avenue

of exposure, a hood or metal canopy closed on each end must be installed

over the sterilizer door. The hood or metal canopy must be connected to

a non-recirculating or dedicated ventilation system or one that exhausts

gases to a well ventilated equipment or other room where workers are not

normally present. A hood or canopy over the sterilizer door is required

for use even with those sterilizers that have a purge cycle and must be

in place by July 1, 1986.

f. Ventilation of sterilizer relief valve. Sterilizers are typically

equipped with a safety relief device to release gas in case of increased

pressure in the sterilizer. Generally, such relief devices are used on

pressure vessels. Although these pressure relief devices are rarely

opened for hospital and health care sterilizers, it is suggested that

they be designed to exhaust vapor from the sterilizer by one of the

following methods:

i. Through a pipe connected to the outlet of the relief valve

ventilated directly outdoors at a point high enough to be away from

passers by, and not near any windows that open, or near any air

conditioning or ventilation air intakes.

ii. Through a connection to an existing or new non-recirculating or

dedicated ventilation system.

iii. Through a connection to a well ventilated equipment or other

room where workers are not normally present.

g. Ventilation systems. Each hospital and health care facility

affected by this notice that uses EtO for the sterilization of equipment

and supplies must have a ventilation system which enables compliance

with the requirements of section (b) through (f) in the

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manner described in these sections and within the timeframes allowed.

Thus, each affected hospital and health care facility must have or

install a non-recirculating or dedicated ventilation equipment or other

room where workers are not normally present in which to vent EtO.

h. Installation of alarm systems. An audible and visual indicator

alarm system must be installed to alert personnel of ventilation system

failures, i.e., when the ventilation fan motor is not working.

2. Workplace Practices

All the workplace practices discussed in this unit must be

permanently posted near the door of each sterilizer prior to use by any

operator.

a. Changing of supply line filters. Filters in the sterilizer liquid

line must be changed when necessary, by the following procedure:

i. Close the cylinder valve and the hose valve.

ii. Disconnect the cylinder hose (piping) from the cylinder.

iii. Open the hose valve and bleed slowly into a proper ventilating

system at or near the in-use supply cylinders.

iv. Vacate the area until the line is empty.

v. Change the filter.

vi. Reconnect the lines and reverse the value position.

vii. Check hoses, filters, and valves for leaks with a fluorocarbon

leak detector (for those sterilizers using the 88 percent

chlorofluorocarbon, 12 percent ethylene oxide mixture (12/88)).

b. Restricted access area. i. Areas involving use of EtO must be

designated as restricted access areas. They must be identified with

signs or floor marks near the sterilizer door, aerator, vacuum pump

floor drain discharge, and in-use cylinder storage.

ii. All personnel must be excluded from the restricted area when

certain operations are in progress, such as discharging a vacuum pump,

emptying a sterilizer liquid line, or venting a non-purge sterilizer

with the door ajar or other operations where EtO might be released

directly into the face of workers.

c. Door opening procedures. i. Sterilizers with purge cycles. A load

treated in a sterilizer equipped with a purge cycle should be removed

immediately upon completion of the cycle (provided no time is lost

opening the door after cycle is completed). If this is not done, the

purge cycle should be repeated before opening door.

ii. Sterilizers without purge cycles. For a load treated in a

sterilizer not equipped with a purge cycle, the sterilizer door must be

ajar 6<gr-thn-eq> for 15 minutes, and then fully opened for at least

another 15 minutes before removing the treated load. The length of time

of the second period should be established by peak monitoring for one

hour after the two 15-minute periods suggested. If the level is above 10

ppm time-weighted average for 8 hours, more time should be added to the

second waiting period (door wide open). However, in no case may the

second period be shortened to less than 15 minutes.

d. Chamber unloading procedures. i. Procedures for unloading the

chamber must include the use of baskets or rolling carts, or baskets and

rolling tables to transfer treated loads quickly, thus avoiding

excessive contact with treated articles, and reducing the duration of

exposures.

ii. If rolling carts are used, they should be pulled not pushed by

the sterilizer operators to avoid offgassing exposure.

e. Maintenance. A written log should be instituted and maintained

documenting the date of each leak detection and any maintenance

procedures undertaken. This is a suggested use practice and is not

required.

i. Leak detection. Sterilizer door gaskets, cylinder and vacuum

piping, hoses, filters, and valves must be checked for leaks under full

pressure with a Fluorocarbon leak detector (for 12/88 systems only)

every two weeks by maintenance personnel. Also, the cylinder piping

connections must be checked after changing cylinders. Particular

attention in leak detection should be given to the automatic solenoid

valves that control the flow of EtO to the sterilizer. Specifically, a

check should be made at the EtO gasline entrance port to the sterilizer,

while the sterilizer door is open and the solenoid valves are in a

closed position.

ii. Maintenance procedures. Sterilizer/areator door gaskets, valves,

and fittings must be replaced when necessary as determined by

maintenance personnel in their bi-weekly checks; in addition, visual

inspection of the door gaskets for cracks, debris, and other foreign

substances should be conducted daily by the operator.

Appendix B to Sec. 1910.1047--Substance Technical Guidelines for

Ethylene Oxide (Non-Mandatory)

i. Physical and Chemical Data

A. Substance identification:

1. Synonyms: dihydrooxirene, dimethylene oxide, EO, 1,2-epoxyethane,

EtO ETO oxacyclopropane, oxane, oxidoethane, alpha/beta-oxidoethane,

oxiran, oxirane.

2. Formula: (C<INF>2</INF> H<INF>4</INF> O).

3. Molecular weight: 44.06

B. Physical data:

1. Boiling point (760 mm Hg): 10.70 [deg]C (51.3 [deg]F);

2. Specific gravity (water = 1): 0.87 (at 20 [deg]C or 68 [deg]F)

3. Vapor density (air = 1): 1.49;

4. Vapor pressure (at 20 [deg]C); 1,095 mm Hg;

5. Solubility in water: complete;

6. Appearance and odor: colorless liquid; gas at temperature above

10.7 [deg]F or 51.3 [deg]C with ether-like odor above 700 ppm.

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ii. Fire, Explosion, and Reactivity Hazard Data

A. Fire:

1. Flash point: less than O [deg]F (open cup);

2. Stability: decomposes violently at temperatures above 800 [deg]F;

3. Flammable limits in air, percent by volume: Lower: 3, Upper: 100;

4. Extinguishing media: Carbon dioxide for small fires, polymer or

alcohol foams for large fires;

5. Special fire fighting procedures: Dilution of ethylene oxide with

23 volumes of water renders it non-flammable;

6. Unusual fire and explosion hazards: Vapors of EtO will burn

without the presence of air or other oxidizers. EtO vapors are heavier

than air and may travel along the ground and be ignited by open flames

or sparks at locations remote from the site at which EtO is being used.

7. For purposes of compliance with the requirements of 29 CFR

1910.106, EtO is classified as a flammable gas. For example, 7,500 ppm,

approximately one-fourth of the lower flammable limit, would be

considered to pose a potential fire and explosion hazard.

8. For purposes of compliance with 29 CFR 1910.155, EtO is

classified as a Class B fire hazard.

9. For purpose of compliance with 29 CFR 1919.307, locations

classified as hazardous due to the presence of EtO shall be Class I.

B. Reactivity:

1. Conditions contributing to instability: EtO will polymerize

violently if contaminated with aqueous alkalies, amines, mineral acids,

metal chlorides, or metal oxides. Violent decomposition will also occur

at temperatures above 800 [deg]F;

2. Incompatabilities: Alkalines and acids;

3. Hazardous decomposition products: Carbon monoxide and carbon

dioxide.

iii. Spill, Leak, and Disposal Procedures

A. If EtO is spilled or leaked, the following steps should be taken:

1. Remove all ignition sources.

2. The area should be evacuated at once and re-entered only after

the area has been thoroughly ventilated and washed down with water.

B. Persons not wearing appropriate protective equipment should be

restricted from areas of spills or leaks until cleanup has been

completed.

C. Waste disposal methods: Waste material should be disposed of in a

manner that is not hazardous to employees or to the general population.

In selecting the method of waste disposal, applicable local, State, and

Federal regulations should be consulted.

iv. Monitoring and Measurement Procedures

A. Exposure above the Permissible Exposure Limit:

1. Eight-hour exposure evaluation: Measurements taken for the

purpose of determining employee exposure under this section are best

taken with consecutive samples covering the full shift. Air samples

should be taken in the employee's breathing zone (air that would most

nearly represent that inhaled by the employee.)

2. Monitoring techniques: The sampling and analysis under this

section may be performed by collection of the EtO vapor on charcoal

adsorption tubes or other composition adsorption tubes, with subsequent

chemical analysis. Sampling and analysis may also be performed by

instruments such as real-time continuous monitoring systems, portable

direct reading instruments, or passive dosimeters as long as

measurements taken using these methods accurately evaluate the

concentration of EtO in employees' breathing zones.

Appendix D describes the validated method of sampling and analysis

which has been tested by OSHA for use with EtO. Other available methods

are also described in Appendix D. The employer has the obligation of

selecting a monitoring method which meets the accuracy and precision

requirements of the standard under his unique field conditions. The

standard requires that the method of monitoring should be accurate, to a

95 percent confidence level, to plus or minus 25 percent for

concentrations of EtO at 1 ppm, and to plus or minus 35 percent for

concentrations at 0.5 ppm. In addition to the method described in

Appendix D, there are numerous other methods available for monitoring

for EtO in the workplace. Details on these other methods have been

submitted by various companies to the rulemaking record, and are

available at the OSHA Docket Office.

B. Since many of the duties relating to employee exposure are

dependent on the results of measurement procedures, employers should

assure that the evaluation of employee exposures is performed by a

technically qualified person.

v. Protective Clothing and Equipment

Employees should be provided with and be required to wear

appropriate protective clothing wherever there is significant potential

for skin contact with liquid EtO or EtO-containing solutions. Protective

clothing shall include impermeable coveralls or similar full-body work

clothing, gloves, and head coverings, as appropriate to protect areas of

the body which may come in contact with liquid EtO or EtO-containing

solutions.

Employers should ascertain that the protective garments are

impermeable to EtO. Permeable clothing, including items made of

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rubber, and leather shoes should not be allowed to become contaminated

with liquid EtO. If permeable clothing does become contaminated, it

should be immediately removed, while the employer is under an emergency

deluge shower. If leather footwear or other leather garments become wet

from EtO they should be discarded and not be worn again, because leather

absorbs EtO and holds it against the skin.

Any protective clothing that has been damaged or is otherwise found

to be defective should be repaired or replaced. Clean protective

clothing should be provided to the employee as necessary to assure

employee protection. Whenever impermeable clothing becomes wet with

liquid EtO, it should be washed down with water before being removed by

the employee. Employees are also required to wear splash-proof safety

goggles where there is any possibility of EtO contacting the eyes.

vi. Miscellaneous Precautions

A. Store EtO in tightly closed containers in a cool, well-ventilated

area and take all necessary precautions to avoid any explosion hazard.

B. Non-sparking tools must be used to open and close metal

containers. These containers must be effectively grounded and bonded.

C. Do not incinerate EtO cartridges, tanks or other containers.

D. Employers should advise employees of all areas and operations

where exposure to EtO occur.

vii. Common Operations

Common operations in which exposure to EtO is likely to occur

include the following: Manufacture of EtO, surfactants, ethanolamines,

glycol ethers, and specialty chemicals, and use as a sterilant in the

hospital, health product and spice industries.

Appendix C to Sec. 1910.1047--Medical Surveillance Guidelines for

Ethylene Oxide (Non-Mandatory)

i. route of entry

Inhalation.

ii. toxicology

Clinical evidence of adverse effects associated with the exposure to

EtO is present in the form of increased incidence of cancer in

laboratory animals (leukemia, stomach, brain), mutation in offspring in

animals, and resorptions and spontaneous abortions in animals and human

populations respectively. Findings in humans and experimental animals

exposed to airborne concentrations of EtO also indicate damage to the

genetic material (DNA). These include hemoglobin alkylation,

unsecheduled DNA synthesis, sister chromatid exchange chromosomal

aberration, and functional sperm abnormalities.

Ethylene oxide in liquid form can cause eye irritation and injury to

the cornea, frostbite, severe irritation, and blistering of the skin

upon prolonged or confined contact. Ingestion of EtO can cause gastric

irritation and liver injury. Other effects from inhalation of EtO vapors

include respiratory irritation and lung injury, headache, nausea,

vomiting, diarrhea, dyspnea and cyanosis.

iii. signs and symptoms of acute overexposure

The early effects of acute overexposure to EtO are nausea and

vomiting, headache, and irritation of the eyes and respiratory passages.

The patient may notice a ``peculiar taste'' in the mouth. Delayed

effects can include pulmonary edema, drowsiness, weakness, and

incoordination. Studies suggest that blood cell changes, an increase in

chromosomal aberrations, and spontaneous abortion may also be causally

related to acute overexposure to EtO.

Skin contact with liquid or gaseous EtO causes characteristic burns

and possibly even an allergic-type sensitization. The edema and erythema

occurring from skin contact with EtO progress to vesiculation with a

tendency to coalesce into blebs with desquamation. Healing occurs within

three weeks, but there may be a residual brown pigmentation. A 40-80%

solution is extremely dangerous, causing extensive blistering after only

brief contact. Pure liquid EtO causes frostbite because of rapid

evaporation. In contrast, the eye is relatively insensitive to EtO, but

there may be some irritation of the cornea.

Most reported acute effects of occupational exposure to EtO are due

to contact with EtO in liquid phase. The liquid readily penetrates

rubber and leather, and will produce blistering if clothing or footwear

contaminated with EtO are not removed.

iv. surveillance and preventive considerations

As noted above, exposure to EtO has been linked to an increased risk

of cancer and reproductive effects including decreased male fertility,

fetotoxicity, and spontaneous abortion. EtO workers are more likely to

have chromosomal damage than similar groups not exposed to EtO. At the

present, limited studies of chronic effects in humans resulting from

exposure to EtO suggest a causal association with leukemia. Animal

studies indicate leukemia and cancers at other sites (brain, stomach) as

well. The physician should be aware of the findings of these studies in

evaluating the health of employees exposed to EtO.

Adequate screening tests to determine an employee's potential for

developing serious

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chronic diseases, such as cancer, from exposure to EtO do not presently

exist. Laboratory tests may, however, give evidence to suggest that an

employee is potentially overexposed to EtO. It is important for the

physician to become familiar with the operating conditions in which

exposure to EtO is likely to occur. The physician also must become

familiar with the signs and symptoms that indicate a worker is receiving

otherwise unrecognized and unacceptable exposure to EtO. These elements

are especially important in evaluating the medical and work histories

and in conducting the physical exam. When an unacceptable exposure in an

active employee is identified by the physician, measures taken by the

employer to lower exposure should also lower the risk of serious long-

term consequences.

The employer is required to institute a medical surveillance program

for all employees who are or will be exposed to EtO at or above the

action level (0.5 ppm) for at least 30 days per year, without regard to

respirator use. All examinations and procedures must be performed by or

under the supervision of a licensed physician at a reasonable time and

place for the employee and at no cost to the employee.

Although broad latitude in prescribing specific tests to be included

in the medical surveillance program is extended to the examining

physician, OSHA requires inclusion of the following elements in the

routine examination:

(i) Medical and work histories with special emphasis directed to

symptoms related to the pulmonary, hematologic, neurologic, and

reproductive systems and to the eyes and skin.

(ii) Physical examination with particular emphasis given to the

pulmonary, hematologic, neurologic, and reproductive systems and to the

eyes and skin.

(iii) Complete blood count to include at least a white cell count

(including differential cell count), red cell count, hematocrit, and

hemoglobin.

(iv) Any laboratory or other test which the examining physician

deems necessary by sound medical practice.

If requested by the employee, the medical examinations shall include

pregnancy testing or laboratory evaluation of fertility as deemed

appropriate by the physician.

In certain cases, to provide sound medical advice to the employer

and the employee, the physician must evaluate situations not directly

related to EtO. For example, employees with skin diseases may be unable

to tolerate wearing protective clothing. In addition those with chronic

respiratory diseases may not tolerate the wearing of negative pressure

(air purifying) respirators. Additional tests and procedures that will

help the physician determine which employees are medically unable to

wear such respirators should include: An evaluation of cardiovascular

function, a baseline chest x-ray to be repeated at five year intervals,

and a pulmonary function test to be repeated every three years. The

pulmonary function test should include measurement of the employee's

forced vital capacity (FVC), forced expiratory volume at one second

(FEV1), as well as calculation of the ratios of FEV1 to FVC, and

measured FVC and measured FEV1 to expected values corrected for

variation due to age, sex, race, and height.

The employer is required to make the prescribed tests available at

least annually to employees who are or will be exposed at or above the

action level, for 30 or more days per year; more often than specified if

recommended by the examining physician; and upon the employee's

termination of employment or reassignment to another work area. While

little is known about the long term consequences of high short-term

exposures, it appears prudent to monitor such affected employees closely

in light of existing health data. The employer shall provide physician

recommended examinations to any employee exposed to EtO in emergency

conditions. Likewise, the employer shall make available medical

consultations including physician recommended exams to employees who

believe they are suffering signs or symptoms of exposure to EtO.

The employer is required to provide the physician with the following

informatin: a copy of this standard and its appendices; a description of

the affected employee's duties as they relate to the employee exposure

level; and information from the employee's previous medical examinations

which is not readily available to the examining physician. Making this

information available to the physician will aid in the evaluation of the

employee's health in relation to assigned duties and fitness to wear

personal protective equipment, when required.

The employer is required to obtain a written opinion from the

examining physician containing the results of the medical examinations;

the physician's opinion as to whether the employee has any detected

medical conditions which would place the employee at increased risk of

material impairment of his or her health from exposure to EtO; any

recommended restrictions upon the employee's exposure to EtO, or upon

the use of protective clothing or equipment such as respirators; and a

statement that the employee has been informed by the physician of the

results of the medical examination and of any medical conditions which

require further explanation or treatment. This written opinion must not

reveal specific findings or diagnoses unrelated to occupational exposure

to EtO, and a copy of the opinion must be provided to the affected

employee.

The purpose in requiring the examining physician to supply the

employer with a

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written opinion is to provide the employer with a medical basis to aid

in the determination of initial placement of employees and to assess the

employee's ability to use protective clothing and equipment.

Appendix D to Sec. 1910.1047--Sampling and Analytical Methods for

Ethylene Oxide (Non-Mandatory)

A number of methods are available for monitoring employee exposures

to EtO. Most of these involve the use of charcoal tubes and sampling

pumps, followed by analysis of the samples by gas chromatograph. The

essential differences between the charcoal tube methods include, among

others, the use of different desorbing solvents, the use of different

lots of charcoal, and the use of different equipment for analysis of the

samples.

Besides charcoal, methods using passive dosimeters, gas sampling

bags, impingers, and detector tubes have been utilized for determination

of EtO exposure. In addition, there are several commercially available

portable gas analyzers and monitoring units.

This appendix contains details for the method which has been tested

at the OSHA Analytical Laboratory in Salt Lake City. Inclusion of this

method in the appendix does not mean that this method is the only one

which will be satisfactory. Copies of descriptions of other methods

available are available in the rulemaking record, and may be obtained

from the OSHA Docket Office. These include the Union Carbide, Dow

Chemical, 3M, and DuPont methods, as well as NIOSH Method S-286. These

methods are briefly described at the end of this appendix.

Employers who note problems with sample breakthrough using the OSHA

or other charcoal methods should try larger charcoal tubes. Tubes of

larger capacity are available. In addition, lower flow rates and shorter

sampling times should be beneficial in minimizing breakthrough problems.

Whatever method the employer chooses, he must assure himself of the

method's accuracy and precision under the unique conditions present in

his workplace.

Ethylene Oxide

Method No.: 30.

Matrix: Air.

Target Concentration: 1.0 ppm (1.8 mg/m\3\).

Procedure: Samples are collected on two charcoal tubes in series and

desorbed with 1% CS<INF>2</INF> in benzene. The samples are derivatized

with HBr and treated with sodium carbonate. Analysis is done by gas

chromatography with an electron capture detector.

Recommended Air Volume and Sampling Rate: 1 liter and 0.05 Lpm.

Detection Limit of the Overall Procedure: 13.3 ppb (0.024 mg/m\3\)

(Based on 1.0 liter air sample).

Reliable Quantitation Limit: 52.2 ppb (0.094 mg/m\3\) (Based on 1.0

liter air sample).

Standard Error of Estimate: 6.59% (See Backup Section 4.6).

Special Requirements: Samples must be analyzed within 15 days of

sampling date.

Status of Method: The sampling and analytical method has been

subjected to the established evaluation procedures of the Organic Method

Evaluations Branch.

Date: August 1981.

Chemist: Wayne D. Potter.

Organic Solvents Branch, OSHA Analytical Laboratory, Salt Lake City,

Utah

1. General Discussion.

1.1 Background.

1.1.1 History of Procedure.

Ethylene oxide samples analyzed at the OSHA Laboratory have normally

been collected on activated charcoal and desorbed with carbon disulfide.

The analysis is performed with a gas chromatograph equipped with a FID

(Flame ionization detector) as described in NIOSH Method S286 (Ref.

5.1). This method is based on a PEL of 50 ppm and has a detection limit

of about 1 ppm.

Recent studies have prompted the need for a method to analyze and

detect ethylene oxide at very low concentrations.

Several attempts were made to form an ultraviolet (UV) sensitive

derivative with ethylene oxide for analysis with HPLC. Among those

tested that gave no detectable product were: p-anisidine,

methylimidazole, aniline, and 2,3,6-trichlorobenzoic acid. Each was

tested with catalysts such as triethylamine, aluminum chloride,

methylene chloride and sulfuric acid but no detectable derivative was

produced.

The next derivatization attempt was to react ethylene oxide with HBr

to form 2-bromoethanol. This reaction was successful. An ECD (electron

capture detector) gave a very good response for 2-bromoethanol due to

the presence of bromine. The use of carbon disulfide as the desorbing

solvent gave too large a response and masked the 2-bromoethanol. Several

other solvents were tested for both their response on the ECD and their

ability to desorb ethylene oxide from the charcoal. Among those tested

were toluene, xylene, ethyl benzene, hexane, cyclohexane and benzene.

Benzene was the only solvent tested that gave a suitable response on the

ECD and a high desorption. It was found that the desorption efficiency

was improved by using 1% CS<INF>2</INF> with the benzene. The carbon

disulfide did not significantly improve the recovery with the other

solvents. SKC Lot 120 was used in all tests done with activated

charcoal.

1.1.2 Physical Properties (Ref. 5.2-5.4).

Synonyms: Oxirane; dimethylene oxide, 1,2-epoxy-ethane; oxane;

C<INF>2</INF> H<INF>4</INF> O; ETO;

Molecular Weight: 44.06

[[Page 351]]

Boiling Point: 10.7 [deg]C (51.3[deg])

Melting Point: -111 [deg]C

Description: Colorless, flammable gas

Vapor Pressure: 1095 mm. at 20 [deg]C

Odor: Ether-like odor

Lower Explosive Limits: 3.0% (by volume)

Flash Point (TOC): Below 0 [deg]F

Molecular Structure: CH<INF>2</INF>--CH<INF>2</INF>

1.2 Limit Defining Parameters.

1.2.1 Detection Limit of the Analytical Procedure.

The detection limit of the analytical procedure is 12.0 picograms of

ethylene oxide per injection. This is the amount of analyte which will

give a peak whose height is five times the height of the baseline noise.

(See Backup Data Section 4.1).

1.2.2 Detection Limit of the Overall Procedure.

The detection limit of the overall procedure is 24.0 ng of ethylene

oxide per sample.

This is the amount of analyte spiked on the sampling device which

allows recovery of an amount of analyte equivalent to the detection

limit of the analytical procedure. (See Backup Data Section 4.2).

1.2.3 Reliable Quantitation Limit.

The reliable quantitation limit is 94.0 nanograms of ethylene oxide

per sample. This is the smallest amount of analyte which can be

quantitated within the requirements of 75% recovery and 95% confidence

limits. (See Backup Data Section 4.2).

It must be recognized that the reliable quantitation limit and

detection limits reported in the method are based upon optimization of

the instrument for the smallest possible amount of analyte. When the

target concentration of an analyte is exceptionally higher than these

limits, they may not be attainable at the routine operating parameters.

In this case, the limits reported on analysis reports will be based on

the operating parameters used during the analysis of the samples.

1.2.4 Sensitivity.

The sensitivity of the analytical procedure over a concentration

range representing 0.5 to 2 times the target concentration based on the

recommended air volume is 34105 area units per [micro]g/mL. The

sensitivity is determined by the slope of the calibration curve (See

Backup Data Section 4.3).

The sensitivity will vary somewhat with the particular instrument

used in the analysis.

1.2.5 Recovery.

The recovery of analyte from the collection medium must be 75% or

greater. The average recovery from spiked samples over the range of 0.5

to 2 times the target concentration is 88.0% (See Backup Section 4.4).

At lower concentrations the recovery appears to be non-linear.

1.2.6 Precision (Analytical Method Only).

The pooled coefficient of variation obtained from replicate

determination of analytical standards at 0.5X, 1X and 2X the target

concentration is 0.036 (See Backup Data Section 4.5).

1.2.7 Precision (Overall Procedure).

The overall procedure must provide results at the target

concentration that are 25% of better at the 95% confidence level. The

precision at the 95% confidence level for the 15 day storage test is

plus or minus 12.9% (See Backup Data Section 4.6).

This includes an additional plus or minus 5% for sampling error.

1.3 Advantages.

1.3.1 The sampling procedure is convenient.

1.3.2 The analytical procedure is very sensitive and reproducible.

1.3.3 Reanalysis of samples is possible.

1.3.4 Samples are stable for at least 15 days at room temperature.

1.3.5 Interferences are reduced by the longer GC retention time of

the new derivative.

1.4 Disadvantages.

1.4.1 Two tubes in series must be used because of possible

breakthrough and migration.

1.4.2 The precision of the sampling rate may be limited by the

reproducibility of the pressure drop across the tubes. The pumps are

usually calibrated for one tube only.

1.4.3 The use of benzene as the desorption solvent increases the

hazards of analysis because of the potential carcinogenic effects of

benzene.

1.4.4 After repeated injections there can be a buildup of residue

formed on the electron capture detector which decreases sensitivity.

1.4.5 Recovery from the charcoal tubes appears to be nonlinear at

low concentrations.

2. Sampling Procedure.

2.1 Apparatus.

2.1.1 A calibrated personal sampling pump whose flow can be

determined within plus or minus 5% of the recommended flow.

2.1.2 SKC Lot 120 Charcoal tubes: glass tube with both ends flame

sealed, 7 cm long with a 6 mm O.D. and a 4-mm I.D., containing 2

sections of coconut shell charcoal separated by a 2-mm portion of

urethane foam. The adsorbing section contains 100 mg of charcoal, the

backup section 50 mg. A 3-mm portion of urethane foam is placed between

the outlet end of the tube and the backup section. A plug of silylated

glass wool is placed in front of the adsorbing section.

2.2 Reagents.

2.2.1 None required.

2.3 Sampling Technique.

2.3.1 Immediately before sampling, break the ends of the charcoal

tubes. All tubes must be from the same lot.

2.3.2 Connect two tubes in series to the sampling pump with a short

section of flexible tubing. A minimum amount of tubing is

[[Page 352]]

used to connect the two sampling tubes together. The tube closer to the

pump is used as a backup. This tube should be identified as the backup

tube.

2.3.3 The tubes should be placed in a vertical position during

sampling to minimize channeling.

2.3.4 Air being sampled should not pass through any hose or tubing

before entering the charcoal tubes.

2.3.5 Seal the charcoal tubes with plastic caps immediately after

sampling. Also, seal each sample with OSHA seals lengthwise.

2.3.6 With each batch of samples, submit at least one blank tube

from the same lot used for samples. This tube should be subjected to

exactly the same handling as the samples (break, seal, transport) except

that no air is drawn through it.

2.3.7 Transport the samples (and corresponding paperwork) to the lab

for analysis.

2.3.8 If bulk samples are submitted for analysis, they shoud be

transported in glass containers with Teflon-lined caps. These samples

must be mailed separately from the container used for the charcoal

tubes.

2.4 Breakthrough.

2.4.1 The breakthrough (5% breakthrough) volume for a 3.0 mg/m

ethylene oxide sample stream at approximately 85% relative humidity, 22

[deg]C and 633 mm is 2.6 liters sampled at 0.05 liters per minute. This

is equivalent to 7.8 [micro]g of ethylene oxide. Upon saturation of the

tube it appeared that the water may be displacing ethylene oxide during

sampling.

2.5 Desorption Efficiency.

2.5.1 The desorption efficiency, from liquid injection onto charcoal

tubes, averaged 88.0% from 0.5 to 2.0 x the target concentration for a

1.0 liter air sample. At lower ranges it appears that the desorption

efficiency is non-linear (See Backup Data Section 4.2).

2.5.2 The desorption efficiency may vary from one laboratory to

another and also from one lot of charcoal to another. Thus, it is

necessary to determine the desorption efficiency for a particular lot of

charcoal.

2.6 Recommended Air Volume and Sampling Rate.

2.6.1 The recommended air volume is 1.0 liter.

2.6.2 The recommended maximum sampling rate is 0.05 Lpm.

2.7 Interferences.

2.7.1 Ethylene glycol and Freon 12 at target concentration levels

did not interfere with the collection of ethylene oxide.

2.7.2 Suspected interferences should be listed on the sample data

sheets.

2.7.3 The relative humidity may affect the sampling procedure.

2.8 Safety Precautions.

2.8.1 Attach the sampling equipment to the employee so that it does

not interfere with work performance.

2.8.2 Wear safety glasses when breaking the ends of the sampling

tubes.

2.8.3 If possible, place the sampling tubes in a holder so the sharp

end is not exposed while sampling.

3. Analytical Method.

3.1 Apparatus.

3.1.1 Gas chromatograph equipped with a linearized electron capture

detector.

3.1.2 GC column capable of separating the derivative of ethylene

oxide (2-bromoethanol) from any interferences and the 1% CS<INF>2</INF>

in benzene solvent. The column used for validation studies was: 10 ft x

\1/8\ inch stainless steel 20% SP-2100, .1% Carbowax 1500 on 100/120

Supelcoport.

3.1.3 An electronic integrator or some other suitable method of

measuring peak areas.

3.1.4 Two milliliter vials with Teflon-lined caps.

3.1.5 Gas tight syringe--500 [micro]L or other convenient sizes for

preparing standards.

3.1.6 Microliter syringes--10 [micro]L or other convenient sizes for

diluting standards and 1 [micro]L for sample injections.

3.1.7 Pipets for dispensing the 1% CS<INF>2</INF> in benzene

solvent. The Glenco 1 mL dispenser is adequate and convenient.

3.1.8 Volumetric flasks--5 mL and other convenient sizes for

preparing standards.

3.1.9 Disposable Pasteur pipets.

3.2 Reagents.

3.2.1 Benzene, reagent grade.

3.2.2 Carbon Disulfide, reagent grade.

3.2.3 Ethylene oxide, 99.7% pure.

3.2.4 Hydrobromic Acid, 48% reagent grade.

3.2.5 Sodium Carbonate, anhydrous, reagent grade.

3.2.6 Desorbing reagent, 99% Benzene/1% CS<INF>2</INF>.

3.3 Sample Preparation.

3.3.1 The front and back sections of each sample are transferred to

separate 2-mL vials.

3.3.2 Each sample is desorbed with 1.0 mL of desorbing reagent.

3.3.3 The vials are sealed immediately and allowed to desorb for one

hour with occasional shaking.

3.3.4 Desorbing reagent is drawn off the charcoal with a disposable

pipet and put into clean 2-mL vials.

3.3.5 One drop of HBr is added to each vial. Vials are resealed and

HBr is mixed well with the desorbing reagent.

3.3.6 About 0.15 gram of sodium carbonate is carefully added to each

vial. Vials are again resealed and mixed well.

3.4 Standard Preparation.

3.4.1 Standards are prepared by injecting the pure ethylene oxide

gas into the desorbing reagent.

[[Page 353]]

3.4.2 A range of standards are prepared to make a calibration curve.

A concentration of 1.0 [micro]L of ethylene oxide gas per 1 mL desorbing

reagent is equivalent to 1.0 ppm air concentration (all gas volumes at

25 [deg]C and 760 mm) for the recommended 1 liter air sample. This

amount is uncorrected for desorption efficiency (See Backup Data Section

4.2. for desorption efficiency corrections).

3.4.3 One drop of HBr per mL of standard is added and mixed well.

3.4.4 About 0.15 grams of sodium carbonate is carefully added for

each drop of HBr (A small reaction will occur).

3.5 Analysis.

3.5.1 GC Conditions.

Nitrogen flow rate--10mL/min.

Injector Temperature--250 [deg]C

Detector Temperature--300 [deg]C

Column Temperature--100 [deg]C

Injection size--0.8 [micro]L

Elution time--3.9 minutes

3.5.2 Peak areas are measured by an integrator or other suitable

means.

3.5.3 The integrator results are in area units and a calibration

curve is set up with concentration vs. area units.

3.6 Interferences.

3.6.1 Any compound having the same retention time of 2-bromoethanol

is a potential interference. Possible interferences should be listed on

the sample data sheets.

3.6.2 GC parameters may be changed to circumvent interferences.

3.6.3 There are usually trace contaminants in benzene. These

contaminants, however, posed no problem of interference.

3.6.4 Retention time data on a single column is not considered proof

of chemical identity. Samples over the 1.0 ppm target level should be

confirmed by GC/Mass Spec or other suitable means.

3.7 Calculations

3.7.1 The concentration in [micro]g/mL for a sample is determined by

comparing the area of a particular sample to the calibration curve,

which has been prepared from analytical standards.

3.7.2 The amount of analyte in each sample is corrected for

desorption efficiency by use of a desorption curve.

3.7.3 Analytical results (A) from the two tubes that compose a

particular air sample are added together.

3.7.4 The concentration for a sample is calculated by the following

equation:

[GRAPHIC] [TIFF OMITTED] TC15NO91.038

where:

A=[micro]g/mL

B=desorption volume in milliliters

C=air volume in liters.

3.7.5 To convert mg/m\3\ to parts per million (ppm) the following

relationship is used:

[GRAPHIC] [TIFF OMITTED] TC15NO91.039

where:

mg/m\3\=results from 3.7.4

24.45=molar volume at 25 [deg]C and 760mm Hg

44.05=molecular weight of ETO.

3.8 Safety Precautions

3.8.1 Ethylene oxide and benzene are potential carcinogens and care

must be exercised when working with these compounds.

3.8.2 All work done with the solvents (preparation of standards,

desorption of samples, etc.) should be done in a hood.

3.8.3 Avoid any skin contact with all of the solvents.

3.8.4 Wear safety glasses at all times.

3.8.5 Avoid skin contact with HBr because it is highly toxic and a

strong irritant to eyes and skin.

4. Backup Data.

4.1 Detection Limit Data.

The detection limit was determined by injecting 0.8 [micro]L of a

0.015 [micro]g/mL standard of ethylene oxide into 1% CS<INF>2</INF> in

benzene. The detection limit of the analytical procedure is taken to be

1.20x10<SUP>-5</SUP> [micro]g per injection. This is equivalent to 8.3

ppb (0.015 mg/m\3\) for the recommended air volume.

4.2 Desorption Efficiency.

Ethylene oxide was spiked onto charcoal tubes and the following

recovery data was obtained.

------------------------------------------------------------------------

Amount spiked Amount recovered

([micro]g) ([micro]g) Percent recovery

------------------------------------------------------------------------

4.5 4.32 96.0

3.0 2.61 87.0

2.25 2.025 90.0

1.5 1.365 91.0

1.5 1.38 92.0

.75 .6525 87.0

.375 .315 84.0

.375 .312 83.2

.1875 .151 80.5

.094 .070 74.5

------------------------------------------------------------------------

At lower amounts the recovery appears to be non-linear.

4.3 Sensitivity Data.

The following data was used to determine the calibration curve.

----------------------------------------------------------------------------------------------------------------

0.5x.75 1x1.5 [micro]g/ 2x3.0 [micro]g/

Injection [micro]g/mL mL mL

----------------------------------------------------------------------------------------------------------------

1............................................................... 30904 59567 111778

2............................................................... 30987 62914 106016

3............................................................... 32555 58578 106122

4............................................................... 32242 57173 109716

X............................................................... 31672 59558 108408

----------------------------------------------------------------------------------------------------------------

Slope=34.105.

4.4 Recovery.

The recovery was determined by spiking ethylene oxide onto lot 120

charcoal tubes

[[Page 354]]

and desorbing with 1% CS<INF>2</INF> in Benzene. Recoveries were done at

0.5, 1.0, and 2.0 X the target concentration (1 ppm) for the recommended

air volume.

Percent Recovery

------------------------------------------------------------------------

Sample 0.5x 1.0x 2.0x

------------------------------------------------------------------------

1...................................... 88.7 95.0 91.7

2...................................... 83.8 95.0 87.3

3...................................... 84.2 91.0 86.0

4...................................... 88.0 91.0 83.0

5...................................... 88.0 86.0 85.0

X...................................... 86.5 90.5 87.0

------------------------------------------------------------------------

Weighted Average=88.2.

4.5 Precision of the Analytical Procedure.

The following data was used to determine the precision of the

analytical method:

------------------------------------------------------------------------

0.5x.75 1x1.5 2x3.0

Concentration [micro]g/ [micro]g/ [micro]g/

mL mL mL

------------------------------------------------------------------------

Injection.............................. .7421 1.4899 3.1184

.7441 1.5826 3.0447

.7831 1.4628 2.9149

.7753 1.4244 2.9185

Average................................ .7612 1.4899 2.9991

Standard Deviation..................... .0211 .0674 .0998

CV..................................... .0277 .0452 .0333

------------------------------------------------------------------------

[GRAPHIC] [TIFF OMITTED] TC15NO91.040

CV+0.036

4.6 Storage Data.

Samples were generated at 1.5 mg/m\3\ ethylene oxide at 85% relative

humidity, 22 [deg]C and 633 mm. All samples were taken for 20 minutes at

0.05 Lpm. Six samples were analyzed as soon as possible and fifteen

samples were stored at refrigerated temperature (5 [deg]C) and fifteen

samples were stored at ambient temperature (23 [deg]C). These stored

samples were analyzed over a period of nineteen days.

Percent Recovery

------------------------------------------------------------------------

Day analyzed Refrigerated Ambient

------------------------------------------------------------------------

1.............................................. 87.0 87.0

1.............................................. 93.0 93.0

1.............................................. 94.0 94.0

1.............................................. 92.0 92.0

4.............................................. 92.0 91.0

4.............................................. 93.0 88.0

4.............................................. 91.0 89.0

6.............................................. 92.0

8.............................................. ............ 92.0

8.............................................. ............ 86.0

10............................................. 91.7

10............................................. 95.5

10............................................. 95.7

11............................................. ............ 90.0

11............................................. ............ 82.0

13............................................. 78.0

13............................................. 81.4

13............................................. 82.4

14............................................. ............ 78.5

14............................................. ............ 72.1

18............................................. 66.0

18............................................. 68.0

19............................................. ............ 64.0

19............................................. ............ 77.0

------------------------------------------------------------------------

4.7 Breakthrough Data.

Breakthrough studies were done at 2 ppm (3.6 mg/m\3\) at

approximately 85% relative humidity at 22 [deg]C (ambient temperature).

Two charcoal tubes were used in series. The backup tube was changed

every 10 minutes and analyzed for breakthrough. The flow rate was 0.050

Lpm.

------------------------------------------------------------------------

Time Percent

Tube No. (minutes) breakthrough

------------------------------------------------------------------------

1.............................................. 10 (\1\)

2.............................................. 20 (\1\)

3.............................................. 30 (\1\)

4.............................................. 40 1.23

5.............................................. 50 3.46

6.............................................. 60 18.71

7.............................................. 70 39.2

8.............................................. 80 53.3

9.............................................. 90 72.0

10............................................. 100 96.0

11............................................. 110 113.0

12............................................. 120 133.9

------------------------------------------------------------------------

\1\ None.

The 5% breakthrough volume was reached when 2.6 liters of test

atmosphere were drawn through the charcoal tubes.

5. References.

5.1 ``NIOSH Manual of Analytical Methods,'' 2nd ed. NIOSH:

Cincinnati, 1977; Method S286.

5.2 ``IARC Monographs on the Evaluation of Carcinogenic Risk of

Chemicals to Man,'' International Agency for Research on Cancer: Lyon,

1976; Vol. II, p. 157.

5.3 Sax., N.I. ``Dangerous Properties of Industrial Materials,'' 4th

ed.; Van Nostrand Reinhold Company. New York, 1975; p. 741.

5.4 ``The Condensed Chemical Dictionary'', 9th ed.; Hawley, G.G.,

ed.; Van Nostrand Reinhold Company, New York, 1977; p. 361.

Summary of Other Sampling Procedures

OSHA believes that served other types of monitoring equipment and

techniques exist for monitoring time-weighted averages. Considerable

research and method development is currently being performed, which will

lead to improvements and a wider variety of monitoring techniques. A

combination of monitoring procedures can be used. There probably is no

one best method for monitoring personal exposure to ethylene oxide in

all cases. There are advantages, disadvantages, and limitations to each

method. The method

[[Page 355]]

of choice will depend on the need and requirements. Some commonly used

methods include the use of charcoal tubes, passive dosimeters, Tedler

gas sampling bags, detector tubes, photoionization detection units,

infrared detection units and gas chromatographs. A number of these

methods are described below.

A. Charcoal Tube Sampling Procedures

Qazi-Ketcham method (Ex. 11-133)--This method consists of collecting

EtO on Columbia JXC activated carbon, desorbing the EtO with carbon

disulfide and analyzing by gas chromatography with flame ionization

detection. Union Carbide has recently updated and revalidated this

monitoring procedures. This method is capable of determining both eight-

hour time-weighted average exposures and short-term exposures. The

method was validated to 0.5 ppm. Like other charcoal collecting

procedures, the method requires considerable analytical expertise.

ASTM-proposed method--The Ethylene Oxide Industry Council (EOIC) has

contracted with Clayton Environmental Consultants, Inc. to conduct a

collaborative study for the proposed method. The ASTM-Proposed method is

similar to the method published by Qazi and Ketcham is the November 1977

American Industrial Hygiene Association Journal, and to the method of

Pilney and Coyne, presented at the 1979 American Industrial Hygiene

Conference. After the air to be sampled is drawn through an activated

charcoal tube, the ethylene oxide is desorbed from the tube using carbon

disulfide and is quantitated by gas chromatography utilizing a flame

ionization detector. The ASTM-proposed method specifies a large two-

section charcoal tube, shipment in dry ice, storage at less

than -5 [deg]C, and analysis within three weeks to prevent migration and

sample loss. Two types of charcoal tubes are being tested--Pittsburgh

Coconut-Based (PCB) and Columbia JXC charcoal. This collaborative study

will give an indication of the inter- and intralaboratory precision and

accuracy of the ASTM-proposed method. Several laboratories have

considerable expertise using the Qazi-Ketcham and Dow methods.

B. Passive Monitors--Ethylene oxide diffuses into the monitor and is

collected in the sampling media. The DuPont Pro-Tek badge collects EtO

in an absorbing solution, which is analyzed colorimetrically to

determine the amount of EtO present. The 3M 350 badge collects the EtO

on chemically treated charcoal. Other passive monitors are currently

being developed and tested. Both 3M and DuPont have submitted data

indicating their dosimeters meet the precision and accuracy requirements

of the proposed ethylene oxide standard. Both presented laboratory

validation data to 0.2 ppm (Exs. 11-65, 4-20, 108, 109, 130).

C. Tedlar Gas Sampling Bags-Samples are collected by drawing a known

volume of air into a Tedlar gas sampling bag. The ethylene oxide

concentration is often determined on-site using a portable gas

chromatograph or portable infrared spectometer.

D. Detector tubes--A known volume of air is drawn through a detector

tube using a small hand pump. The concentration of EtO is related to the

length of stain developed in the tube. Detector tubes are economical,

easy to use, and give an immediate readout. Unfortunately, partly

because they are nonspecific, their accuracy is often questionable.

Since the sample is taken over a short period of time, they may be

useful for determining the source of leaks.

E. Direct Reading Instruments--There are numerous types of direct

reading instruments, each having its own strengths and weaknesses (Exs.

135B, 135C, 107, 11-78, 11-153). Many are relatively new, offering

greater sensitivity and specificity. Popular ethylene oxide direct

reading instruments include infrared detection units, photoionization

detection units, and gas chromatographs.

Portable infrared analyzers provide an immediate, continuous

indication of a concentration value; making them particularly useful for

locating high concentration pockets, in leak detection and in ambient

air monitoring. In infrared detection units, the amount of infrared

light absorbed by the gas being analyzed at selected infrared

wavelengths is related to the concentration of a particular component.

Various models have either fixed or variable infrared filters, differing

cell pathlengths, and microcomputer controls for greater sensitivity,

automation, and interference elimination.

A fairly recent detection system is photoionization detection. The

molecules are ionized by high energy ultraviolet light. The resulting

current is measured. Since different substances have different

ionization potentials, other organic compounds may be ionized. The lower

the lamp energy, the better the selectivity. As a continuous monitor,

photoionization detection can be useful for locating high concentration

pockets, in leak detection, and continuous ambient air monitoring. Both

portable and stationary gas chromatographs are available with various

types of detectors, including photoionization detectors. A gas

chromatograph with a photoionization detector retains the photionization

sensitivity, but minimizes or eliminates interferences. For several GC/

PID units, the sensitivity is in the 0.1-0.2 ppm EtO range. The GC/PID

with microprocessors can sample up to 20 sample points sequentially,

calculate and record data, and activate alarms or ventilation systems.

Many are quite flexible and can be configured to meet the specific

analysis needs for the workplace.

[[Page 356]]

DuPont presented their laboratory validation data of the accuracy of

the Qazi-Ketcham charcoal tube, the PCB charcoal tube, Miran 103 IR

analyzer, 3M <greek-i>3550 monitor and the Du Pont C-70 badge. Quoting

Elbert V. Kring:

We also believe that OSHA's proposed accuracy in this standard is

appropriate. At plus or minus 25 percent at one part per million, and

plus or minus 35 percent below that. And, our data indicates there's

only one monitoring method, right now, that we've tested thoroughly,

that meets that accuracy requirements. That is the Du Pont Pro-Tek

badge* * *. We also believe that this kind of data should be confirmed

by another independent laboratory, using the same type dynamic chamber

testing (Tr. 1470)

Additional data by an independent laboratory following their exact

protocol was not submitted. However, information was submitted on

comparisons and precision and accuracy of those monitoring procedures

which indicate far better precision and accuracy of those monitoring

procedures than that obtained by Du Pont (Ex. 4-20, 130, 11-68, 11-133,

130, 135A).

The accuracy of any method depends to a large degree upon the skills

and experience of those who not only collect the samples but also those

who analyze the samples. Even for methods that are collaboratively

tested, some laboratories are closer to the true values than others.

Some laboratories may meet the precision and accuracy requirements of

the method; others may consistently far exceed them for the same method.

[49 FR 25796, June 22, 1984, as amended at 50 FR 9801, Mar. 12, 1985; 50

FR 41494, Oct. 11, 1985; 51 FR 25053, July 10, 1986; 53 FR 11436, 11437,

Apr. 6, 1988; 53 FR 27960, July 26, 1988; 54 FR 24334, June 7, 1989; 61

FR 5508, Feb. 13, 1996; 63 FR 1292, Jan. 8, 1998; 67 FR 67965, Nov. 7,

2002; 70 FR 1143, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR

50190, Aug. 24, 2006]