Glossary - MSA ORION Manual

Four-Head Gas Detector: MSA Orion
G l o s s a r y
auto-ignition temperature: See ignition temperature.
calibration gas value:
carbon disulphide:
carbon monoxide:
datalog:
Gas Help
hydrogen sulphide:
ignition temperature:
Immediately Dangerous to
Life and Health (IDLH):
Lower Explosive Limit
(LEL):
mist:
parts per million (ppm):
Short Term Exposure Limit
(STEL):
Threshold Limit Value
(TLV):
D.I. Recommended Practice
FILE: W:\NB\RP HMRU\Orion\Frame Ver 02\Appendix.fm
A known concentration of gas against which the Orion is calibrated and
spanned.
Carbon disulphide (or carbon bisulphide) is an industrial chemical used as a
solvent, fumigant, and in mining and manufacturing. Chemical formula is CS
and CAS No is 75-15-0. Its ignition temperature is 90
it has a low ignition energy, and it is heavier than air.
A colourless, odourless gas produced by the incomplete combustion of fossil
fuels. Carbon monoxide is lethal because it reacts with the oxygen-carrying
substance in the blood, haemoglobin. The haemoglobin is then unavailable to
react with oxygen in the lungs, causing asphyxiation. Carbon monoxide is
present in smoke, including bushfire smoke, is often present after fires, in
exhausts from internal combustion engines, and is used in the steel industry.
CO is combustible, with an LEL of 12.5% by volume.
Record of measured gas concentrations, including time and date, stored in the
instrument's electronic memory.
A 24 hour, seven day a week help service for the Orion gas detector (and some
other gas detectors). Use the number listed on the Online Phone Book page on
the Intranet. Call for advice on using, maintaining, problem solving and
ordering spare parts for the Orion 4-head gas detector. Spare parts queries are
best sent during daylight hours.
A colourless, poisonous gas with the odour of rotten eggs. Often produced by
decaying animal or vegetable matter.
The temperature of a gas or vapour is the temperature at which it will ignite
without a flame or spark being present.
The maximum concentration of gas (in ppm) from which a worker could
escape within 30 minutes without experiencing any escape-impairing or
irreversible health effects.
Sometimes referred to as Lower Flammable Limit (LFL). The minimum
concentration of a gas – in a mixture of that gas and air – which will ignite. A
common unit of measurement is a percent of the LEL.
A suspension of finely divided liquid particles suspended in the atmosphere.
Examples are an oil mist produced during cutting and grinding operations, acid
mists from electroplating, acid or alkali mists from pickling operations, and
paint spray mist in painting operations. Fog and cloud are both examples of
mists that occur when water vapour in the atmosphere condenses.
A common unit of measurement for toxic gases. This term literally means one
part out of one million possible parts. 10,000 ppm is 1% by volume for gases.
The average amount of gas (in ppm) a worker can be exposed to in a 15 minute
period with no long term health effects. This may occur 4 times a shift with one
hour between 15 minute exposures.
A term used to signify limits in gas exposure. TLV is a proprietary term and is
not normally used by Fire and Rescue NSW. TLV is usually expressed as a
TWA.
o
C, flash point is –30
Version 02 Issued February 2011
© Copyright State of NSW (Fire and Rescue NSW) 2011
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C,