Action level. An airborne concentration
of ethylene oxide (EtO) of 0.5 parts per million, calculated as an
eight-hour time-weighted average.
Authorized personnel. Individuals
specifically permitted by the employer to enter the exposure control
area to perform necessary duties, or to observe employee exposure
evaluations.
Breathing zone. The space around and in
front of an employee's nose and mouth, forming a hemisphere with a
six-to nine-inch radius.
CAS (Chemical Abstract Service) number.
CAS numbers are internationally recognized and used on safety data
sheets (SDSs) and other documents to identify substances. For more
information see http://www.cas.org/about.
Container. Any container, except for
pipes or piping systems that contains ethylene oxide. It can be any
of the following:
(a) Barrel.
(b) Bottle.
(c) Can.
(d) Cylinder.
(e) Drum.
(f) Reaction vessel.
(g) Storage tank.
Day. Any part of a calendar day.
Director. The director means the
director of the department of labor and industries or their
designee.
Emergency. Any event that could or does
result in the unexpected significant release of ethylene oxide.
Examples of emergencies include equipment failure, container rupture,
or control equipment failure.
Ethylene oxide (EtO). Is an organic
chemical represented by the CAS registry number 75-21-8. EtO is a
flammable colorless gas and is commonly used to sterilize medical
equipment and as a fumigant for certain agricultural products. It is
also used as an intermediary in the production of various chemicals
such as ethylene glycol, automotive antifreeze, and
polyurethane.
Exposure. The contact an employee has
with ethylene oxide, whether or not protection is provided by
respirators or other personal protective equipment (PPE). Exposure
can occur through various routes of entry such as inhalation,
ingestion, skin contact, or skin absorption.
Licensed health care professional
(LHCP). An individual whose legally permitted scope of
practice allows him or her to provide some or all of the health care
services required for medical evaluations.
Permissible exposure limits (PELs). PELs
are employee exposures to toxic substances or harmful physical agents
that must not be exceeded. PELs are specified in applicable WISHA
rules. The PELs for ethylene oxide (EtO) are:
(a) Eight-hour time-weighted average
(TWA8) of one part per million (ppm);
and
(b)Fifteen-minute short-term exposure limit (STEL) of
five ppm.
Short-term exposure limit (STEL). An
exposure limit averaged over a short time period (usually fifteen
minutes) that must not be exceeded during any part of an employee's
workday.
Time-weighted average
(TWA8). An exposure limit averaged over
an eight-hour period that must not be exceeded during an employee's
workday.
