Whitedamp is a noxious mixture of gases formed by the
combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combus ...
of coal, usually in an enclosed environment such as a
coal mine
Coal mining is the process of extracting coal from the ground. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from ...
. The main, most toxic constituent is
carbon monoxide
Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simpl ...
, which causes
carbon monoxide poisoning
Carbon monoxide poisoning typically occurs from breathing in carbon monoxide (CO) at excessive levels. Symptoms are often described as " flu-like" and commonly include headache, dizziness, weakness, vomiting, chest pain, and confusion. Large ...
.
Hydrogen sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The under ...
, also called
stinkdamp, may co-occur. Coal frequently starts to
burn slowly in mines when it is exposed to the
atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A ...
;
partial combustion produces carbon monoxide. The term is etymologically and practically related to terms for other underground mine gases such as
firedamp,
black damp
Blackdamp (also known as stythe or choke damp) is an asphyxiant, reducing the available oxygen content of air to a level incapable of sustaining human or animal life. It is not a single gas but a mixture of unbreathable gases left after oxygen is ...
, stink damp, and
afterdamp.
Etymology
The meaning of "damp" in this term, while most commonly understood to imply humidity, presents evidence of having been separated from that newer, irrelevant meaning at least by the first decade of the 18th century, where the original relevant meaning of "vapor" derives from a Proto-Germanic origin, ''dampaz'', which gave rise to its immediate English predecessor, the Middle Low German ''damp'' (with no record of an Old English intermediary). The proto-Germanic ''dampaz'' gave rise to many other cognates, including the Old High German ''damph'', the Old Norse ''dampi'', and the modern German ''Dampf'', the last of which still translates as "vapor".
[Harper, D. (n.d.). Etymology of fire-damp. Online Etymology Dictionary. Retrieved January 6, 2022, fro]
this link
Detection
Traditionally, whitedamp (specifically carbon monoxide) was detected by its effect on
canaries, who succumb much more quickly than humans. However, there are now
gas detector
A gas detector is a device that detects the presence of gases in an area, often as part of a safety system. A gas detector can sound an alarm to operators in the area where the leak is occurring, giving them the opportunity to leave. This type of ...
s available; these detect toxic gases at very low levels. The levels of gas detection depend on the gas and methods used.
Carbon monoxide detectors
A carbon monoxide detector or CO detector is a device that detects the presence of the carbon monoxide (CO) gas to prevent carbon monoxide poisoning. In the late 1990s Underwriters Laboratories changed the definition of a single station CO d ...
are common in homes.
References
*JS Haldane and
JG Priestley, ''Respiration'', Oxford University Press, 2nd Ed (1935)
Coal mining
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