A short-term exposure limit (STEL) is the acceptable average exposure over a short period of time, usually 15 minutes as long as the time-weighted average is not exceeded.
STEL is a term used in
occupational health
Occupational safety and health (OSH), also commonly referred to as occupational health and safety (OHS), occupational health, or occupational safety, is a multidisciplinary field concerned with the safety, health, and welfare of people at wor ...
,
industrial hygiene
Occupational hygiene (United States: industrial hygiene (IH)) is the anticipation, recognition, evaluation, control, and confirmation (ARECC) of protection from hazards at work that may result in injury, illness, or affect the well being of work ...
and
toxicology
Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating expo ...
. The STEL may be a
legal
Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior,Robertson, ''Crimes against humanity'', 90. with its precise definition a matter of longstanding debate. It has been vario ...
limit in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
for exposure of an employee to a
chemical substance
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wi ...
. The
Occupational Safety and Health Administration
The Occupational Safety and Health Administration'' (OSHA ) is a large regulatory agency of the United States Department of Labor that originally had federal visitorial powers to inspect and examine workplaces. Congress established the agenc ...
(U.S. OSHA) has set OSHA-STELs for
1,3-butadiene
1,3-Butadiene () is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two viny ...
,
benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...
and
ethylene oxide
Ethylene oxide is an organic compound with the chemical formula, formula . It is a cyclic ether and the simplest epoxide: a three-membered Ring (chemistry), ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless a ...
. For chemicals, STEL assessments are usually done for 15 minutes and expressed in
parts per million
In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they ...
(ppm), or sometimes in
milligram
The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce worldwide, and is often simply called a kilo colloquially. ...
s per cubic meter (mg/m
3).
The
American Conference of Governmental Industrial Hygienists
The American Conference of Governmental Industrial Hygienists (ACGIH) is a professional association of industrial hygienists and practitioners of related professions, with headquarters in Cincinnati, Ohio. One of its goals is to advance worker pr ...
publishes a more extensive list of STELs as
threshold limit values (TLV-STEL).
Similar national exposure limits
*United Kingdom
**COSHH (''Control of Substances Hazardous to Health'').
*Australia
**OES Occupational Exposure Standard
OES Occupational Exposure Standard
*France
**VLEP 8h00 ('' Valeur Limite d’Exposition Professionnelle 8h00'')
**VLEP CT ('' Valeur Limite d’Exposition Professionnelle Court Terme'')
*Netherlands
**MAC ('' Maximaal Aanvaarde Concentratie'')
*Malaysia
**PEL (''Permissible Exposure Limits'')
*Poland
**NDSCh ('' Najwyższe dopuszczalne stężenie chwilowe'')
*Russia
**ПДК ('' предельно допустимая концентрация'')
See also
* Permissible exposure limit
The permissible exposure limit (PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a chemical substance or physical agent such as high level noise. Permissible exposure limits are established by the Occupational S ...
* Exposure action value
An Exposure Action Value (EAV) or Action Value (AV) is a limit set on occupational exposure to noise where, when those values are exceeded, employers must take steps to monitor the exposure levels. These levels are measured in decibels. The Ameri ...
Notes
{{DEFAULTSORT:Short-Term Exposure Limit
Concentration indicators
Industrial hygiene
Occupational safety and health
Toxicology