Ethylene Oxide (EtO) Safety

EtO hazards and exposure limits

The standard applies to all occupational exposures to EtO, except products shown by objective data not to release EtO at or above the action level or above the excursion limit.

EtO hazards include cancer, reproductive effects, mutagenicity, central nervous system effects, skin sensitization, skin, eye and respiratory tract irritation, acute toxicity and flammability.

Reference: 29 CFR 1910.1047(a)(1) · 29 CFR 1910.1047(b) · 29 CFR 1910.1047(c) · 29 CFR 1910.1047(j)(1)(ii) · 29 CFR 1910.1047(a)(2) · 29 CFR 1910.1047(c)(1) · 29 CFR 1910.1047(c)(2)

Monitoring and notification

• Exposure is determined from breathing zone air samples representing the 8-hour TWA and 15-minute exposures of each employee.
• After initial monitoring: at or above the action level but at or below the TWA, repeat at least every 6 months; above the TWA, at least every 3 months; above the excursion limit, at least every 3 months.
• Monitoring may stop when two consecutive measurements at least 7 days apart are below the action level (or at or below the excursion limit for short-term monitoring).
• Monitor again after changes in production, process, controls, personnel or work practices that may increase exposure.
• You are notified within 15 working days of the employer receiving results, including corrective action if a limit was exceeded.

Reference: 29 CFR 1910.1047(d) · 29 CFR 1910.1047(d)(1)(i) · 29 CFR 1910.1047(d)(3)(i) · 29 CFR 1910.1047(d)(3)(ii) · 29 CFR 1910.1047(d)(3)(iv) · 29 CFR 1910.1047(d)(4)(ii) · 29 CFR 1910.1047(d)(4)(iv) · 29 CFR 1910.1047(d)(5) · 29 CFR 1910.1047(d)(7)(i) · 29 CFR 1910.1047(d)(7)(ii)

Regulated areas and signs

• A regulated area is established wherever exposure may exceed the TWA, or EtO exceeds or can reasonably be expected to exceed the excursion limit. Access is limited to authorized persons, and the area is marked to minimize the number of employees inside.
• Signs at regulated areas and their entrances read: DANGER, ETHYLENE OXIDE, MAY CAUSE CANCER, MAY DAMAGE FERTILITY OR THE UNBORN CHILD, RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING MAY BE REQUIRED IN THIS AREA, AUTHORIZED PERSONNEL ONLY.
• Containers of EtO that could cause exposure at or above the action level or above the excursion limit are labeled.

Reference: 29 CFR 1910.1047(e) · 29 CFR 1910.1047(j)(2) · 29 CFR 1910.1047(e)(1) · 29 CFR 1910.1047(e)(2) · 29 CFR 1910.1047(e)(3) · 29 CFR 1910.1047(j)(2)(i)(A) · 29 CFR 1910.1047(j)(2)(ii)(A)

Controls and respirators

• Engineering controls and work practices come first, except to the extent they are not feasible; where they are not enough, respirators supplement them. Engineering controls are generally infeasible for collecting quality assurance samples from sterilized materials, removing biological indicators from sterilized materials, loading and unloading tank cars, changing EtO tanks on sterilizers, and vessel cleaning. Respirators must be used for work where engineering and work-practice controls are not feasible.
• Where the TWA or excursion limit is exceeded, the employer has a written compliance program that includes a schedule for periodic leak detection surveys and a written plan for emergency situations. The written program plans are reviewed at least every 12 months. Employee rotation may not be used to comply.
• Half masks of any type must not be used, because EtO may cause eye irritation or injury. Air-purifying full facepiece respirators use a canister approved for EtO.
• Where eye or skin contact is possible, protective clothing and equipment are provided at no cost and must be worn.

Reference: 29 CFR 1910.1047(f) · 29 CFR 1910.1047(g) · 29 CFR 1910.1047(f)(1)(i) · 29 CFR 1910.1047(f)(1)(ii) · 29 CFR 1910.1047(f)(1)(iii) · 29 CFR 1910.1047(g)(1)(ii) · 29 CFR 1910.1047(f)(2)(i) · 29 CFR 1910.1047(f)(2)(ii) · 29 CFR 1910.1047(f)(2)(iii) · 29 CFR 1910.1047(f)(2)(iv) · 29 CFR 1910.1047(g)(3)(i) · 29 CFR 1910.1047(g)(3)(ii) · 29 CFR 1910.1047(g)(4)

Emergencies

An emergency is an occurrence such as equipment failure, container rupture or control failure likely to cause an unexpected significant release of EtO.

• Each workplace with the possibility of an emergency has a written emergency plan, including emergency action and fire prevention plan elements.
• Employees correcting emergency conditions wear respiratory protection until the emergency is abated.
• There is a means to alert potentially affected employees promptly, and affected employees are immediately evacuated.

Reference: 29 CFR 1910.1047(h) · 29 CFR 1910.1047(b) · 29 CFR 1910.1047(h)(1)(i) · 29 CFR 1910.1047(h)(1)(ii) · 29 CFR 1910.1047(h)(1)(iii) · 29 CFR 1910.1047(h)(2)

Medical surveillance and training

Medical surveillance covers employees who are or may be exposed at or above the action level for at least 30 days a year (regardless of respirator use), and is made available to anyone exposed in an emergency. Exams are given before assignment, at least annually, at termination or reassignment, and as soon as possible when an employee reports symptoms of overexposure or wants advice about effects on their ability to have a healthy child. Exams are free, without loss of pay, at a reasonable time and place.

Training is provided at initial assignment and at least annually to employees potentially exposed at or above the action level or above the excursion limit. It covers how to detect EtO (such as monitoring and continuous monitors), its physical and health hazards, protective measures and procedures, and the hazard communication program.

Reference: 29 CFR 1910.1047(i) · 29 CFR 1910.1047(j)(3) · 29 CFR 1910.1047(i)(1)(i)(A) · 29 CFR 1910.1047(i)(1)(i)(B) · 29 CFR 1910.1047(i)(1)(ii) · 29 CFR 1910.1047(i)(2)(i)(A) · 29 CFR 1910.1047(i)(2)(i)(B) · 29 CFR 1910.1047(i)(2)(i)(C) · 29 CFR 1910.1047(i)(2)(i)(E) · 29 CFR 1910.1047(j)(3)(i) · 29 CFR 1910.1047(j)(3)(iii)(A) · 29 CFR 1910.1047(j)(3)(iii)(B) · 29 CFR 1910.1047(j)(3)(iii)(C) · 29 CFR 1910.1047(j)(3)(iii)(D)