For the purposes of this regulation, the following definitions shall apply:

1. "Acute care facility" means any facility currently licensed by the California Department of Health Services

as a general acute care hospital (as defined in Title 22, CCR, Section 70005), or any military hospital.

2. "Aeration" is the process during which residual ethylene oxide dissipates, whether under forced air flow,

natural or mechanically assisted convection, or other means, from previously sterilized materials after the sterilizer

cycle is complete.

3. "Aeration-only facility" means a facility which performs aeration on materials which have been sterilized

with ethylene oxide at another facility.

4. "Aerator" means any equipment or space in which materials previously sterilized with ethylene oxide are

placed or remain for the purpose of aeration. An aerator is not any equipment or space in which materials

that have previously undergone ethylene oxide sterilization and aeration can be handled, stored, and

transported in the same manner as similar materials that have not been sterilized with ethylene oxide.

5. "Aerator exhaust stream" means all ethylene oxide-contaminated air which is emitted from an aerator.

6. "Back-draft valve exhaust stream" is the air stream which results from collection of ethylene oxide-

contaminated air which may be removed from the sterilizer through a back-draft valve or rear chamber

exhaust system during unloading of the sterilized materials.

7. "Control device" means an article, machine, equipment, or contrivance which reduces the amount of

ethylene oxide between its inlet and outlet and which is sized, installed, operated, and maintained according to

good engineering practices, as determined by the District.

8. "Control efficiency" is the ethylene oxide (EtO) mass or concentration reduction efficiency of a control

device, as measured with ARB Test Method 431 (Title 17, CCR, Section 94143) according to the source

testing requirements herein, and expressed as a percentage calculated across the control device as follows:

~ EtO in - ~ EtO out x 100 = % Control Efficiency

~ EtO in

9. "Date of compliance" means the time from District adoption of regulations enacting this control measure

until a facility must be in compliance with specific requirements of this rule.

10. "District" means the local air pollution control district or air quality management district.

11. "Ethylene oxide (EtO)" is the substance identified as a toxic air contaminant by the Air Resources Board in

17 CCR, Section 93000.

12. "Facility" means an entity or entities which: own or operate a sterilizer or aerator, are owned or operated

by the same person or persons, and are located on the same parcel or contiguous parcels.

13. "Facility-wide pounds of ethylene oxide used per year" is the total pounds of ethylene oxide used in all of

the sterilizers at the facility during a one-year period.

14. "Leak-free" refers to that state which exists when the concentration of sterilant gas measured 1 cm. away

from any portion of the exhaust system of a sterilizer or aerator, during conditions of maximum sterilant gas

mass flow, is less than:

A. 30 ppm for sterilant gas composed of 12% ethylene oxide/88% chlorofluorocarbon-12 by weight;


B. 10 ppm for other compositions of sterilant gas,

as determined by ARB Test Method 21 (Title 17, CCR, Section 94124) using a portable flame ionization

detector or a non-dispersive infrared analyzer, calibrated with methane, or an acceptable alternative method or

analytical instrument approved by the District. A chlorofluorocarbon-12 specific audible detector using a metal

oxide semi-conductor sensor shall be considered an acceptable alternative for exhaust systems carrying a

sterilant gas mixture of ethylene oxide and chlorofluorocarbon-12.

15. "Local medical emergency" means an unexpected occurrence in the area served by the acute care facility

resulting in a sudden increase in the amount of medical treatments which require a significant increase in the

operation of a sterilizer or aerator.

16. "Sterilant gas" means ethylene oxide or any combination of ethylene oxide and (an)other gas(es) used in a


17. "Sterilizer" means any equipment in which ethylene oxide is used as a biocide to destroy bacteria, viruses,

fungi, and other unwanted organisms on materials. Equipment in which ethylene oxide is used to fumigate

foodstuffs is considered a sterilizer.

18. "Sterilizer cycle" means the process which begins when ethylene oxide is introduced into the sterilizer,

includes the initial purge or evacuation after sterilization and subsequent air washes, and ends after evacuation

of the final air wash.

19. "Sterilizer door hood exhaust stream" is the air stream which results from collection of fugitive ethylene

oxide emissions, by means of an existing hood over the sterilizer door, during the time that the sterilizer door

is open after the sterilizer cycle has been completed.

20. "Sterilizer exhaust stream" is all ethylene oxide-contaminated air which is intentionally removed from the

sterilizer during the sterilizer cycle.

21. "Sterilizer exhaust vacuum pump" means a device used to evacuate the sterilant gas during the sterilizer

cycle, including any associated heat exchanger. A sterilizer exhaust vacuum pump is not a device used solely to

evacuate a sterilizer prior to the introduction of ethylene oxide.