The early symptoms of blackdamp (drowsiness, dizziness, and light-headedness) are easily mistaken for simple fatigue however lethal doses will cause asphyxiation that can easily result in death within seconds. While not toxic in itself, once carbon dioxide is mixed with the air it reduces the available oxygen one can breathe. Originally a candle with a naked flame would be an indicator of an unsafe atmosphere depending on the change to the flame tip.Īs you can imagine, a flame is a pretty clear means of ignition, so when it got too close to the gas explosions would take place.įollowing from this, the safety lamp was developed to provide the coal mines with a means of testing for gases while still being able to operate in potentially flammable or explosive air.īlack damp is the mining term for the suffocating mixture of carbon dioxide and other unbreathable gases that can build-up in mines causing poisoning, asphyxiation, and ultimately death if left untreated.Ĭarbon dioxide (CO2) is a colourless, noxious gas that only gives off a slight acrid smell at higher concentrations making it very hard to identify through human senses. This was often done through the use of a testing flame. This is done through quality mine ventilation.įind out how Howden have taken an evolutionary leap forward in the concept, design, engineering, equipment and control of mine ventilation -Īnd secondly, any dangerous gases must be detected and monitored. It makes sense then to firstly avoid the build-up of this highly flammable gas. When humans do not receive enough oxygen to the brain it can cause headaches, nausea, dizziness, and can ultimately result in death when the oxygen concentration drops below 6%. Methane in sufficient quantities is also capable of displacing oxygen from the air and can cause asphyxia in humans who breathe it in. All it takes is a naked flame or a spark from a machine to cause an explosion when these levels of methane are in the air. The riskiest level of methane in the air is said to be 9.5% where it finds the perilous balance. Below that range there isn’t enough to be ignited, and above that range the mixture is too dense to be explosive. Methane is only combustible at levels between 4 and 16%. Because it’s much lighter than air it tends to accumulate at higher levels within enclosed spaces where little ventilation exists to disperse it. Methane has a density relative to air of 0.55. As the pockets are penetrated by the mining machinery the gas seeps into the pit where explosive mixtures of methane can form. Methane gas accumulates in “pockets” of the coal and adjacent strata naturally over millions of years and can be released as the coal is mined. It occurs naturally in coal seams and shale deposits and is a major component of the natural gas that we burn for energy. Methane (CH4) is a colourless, odourless, highly flammable, and highly explosive noxious gas. It’s mostly made up of methane and methane is often an interchangeable term when miners talk about firedamp. They are:įiredamp is a mining term for a set of explosive gases found in mines. The most efficient way of preventing these gases in mines is the incorporation of high quality mining ventilation systems as well as the use of early detection devices.Ī dangerous mine atmosphere is one that is toxic or explosive and there are several damps that create this kind of atmosphere. These damps are produced or released during mining operations including drilling and blasting, by mining machinery such as diesel and gasoline motors, and by other means such as the decay of timbers, the aftereffects of mine fires, and chemical processes like oxidation. Rather than one particular gas they are a toxic or explosive mixture of different gases that have a varying effect on human health and mine safety. This name comes from the German word Dampf meaning “ vapour”. These other gases are often referred to as mine damps. The air in mines can be contaminated by the presence of other gases such as carbon monoxide, hydrogen sulfide, methane, and excess of carbon dioxide.ĭue to being in a confined space these gases are not always able to disperse and can therefore build up in the mine, and due to their combustible, explosive, or toxic qualities this is a serious issue. When other gases contaminant the air, the oxygen levels drop, and that is when the trouble begins. We breathe easiest with 21% oxygen present in the air. The air we breathe on the surface is a mixture of several gases including oxygen, nitrogen, argon, carbon dioxide, and other gases in trace amounts. It goes without saying that we need air to live and breathe.
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