Firedamp, a term for flammable gases found in mines, can cause explosions and fires. Methane is the most common component, and specialty lamps were used to reduce the risk of ignition. Afterhumid gases, which can cause asphyxiation, are also a danger in mines.
All gases that can be found in a mine, with the exception of breathable air, have historically been referred to as wet. This term is thought to have originated from the word wetf, which is German for steam. Firedamp in particular refers to any number of different flammable gases that may be encountered in the mining process. These firedamp gases can build up in deposits, such as coal seams or other underlying rock formations, so any amount of open flame in an active coal mine can potentially lead to a destructive fire or explosion. Specialty lamps were used which utilized very fine mesh screens to reduce the possibility of firedamp ignition before safe electric light was available.
Any explosive gas mixture found in a mine can constitute firedamp, although methane is the most common component. These flammable gases can be found under a variety of different circumstances, although bituminous coal mines tend to have a large amount of associated methane. Modern mining techniques can extract these methane deposits by injecting carbon dioxide (CO2), but the presence of these flammable gases was historically just one of many dangers associated with coal mining.
Because methane is often found in and between coal seams, early mining operations often released it when it hit a seam. In some cases, a spark from a pickaxe or other ignition source would immediately cause the released methane to ignite or explode. It was also possible for the firedamp to enter an existing tunnel or shaft where it could subsequently be ignited by a lamp, airborne coal dust, or by other means.
Special lamps have been built that could help reduce the likelihood of a firedamp explosion. This was achieved by enclosing the lamp flame in a fine mesh. The mesh material could allow methane to pass into the lamp body and be burned by the flame, but the holes were fine enough to contain the flame itself. Since the flame would tend to flare up in the presence of flammable gases, these lamps were also used to determine whether firedamp was present in a specific tunnel.
Following a firedamp explosion, other dangerous gases were often released. These gases, which can consist of carbon monoxide (CO), carbon dioxide, and nitrogen, are referred to as afterhumid. Because they tend to be odorless, these gases can cause asphyxiation in miners, which has led to the practice of bringing small rodents or birds into the mines. These small animals typically react to the presence of residual moisture in time for human miners to retreat to an area with breathable air.
Protect your devices with Threat Protection by NordVPN
