EM103 : HAZARD RECOGNITION - MINE GASES
Document Summary
Gas detection: gas detection is an important part of any rescue or recovery operation. Your team will make frequent tests for gases as it advances beyond the fresh air base. The amount of carbon monoxide indicates something about the extent of that fire. Effects of temperature and pressure: pressure increases - gas contracts, pressure decreases - gas expands, temperature increases - gas expands, temperature decreases - gas contracts. Atmospheric pressure: pressure exerted on a gas is usually atmospheric pressure. Atmospheric pressure is measured on a barometer: a rise in the barometric reading indicates an increase in pressure, a drop in barometric reading indicates a decrease in pressure, atmospheric pressure affects the diffusion rate of a gas. For example, if the barometer rises, indicating increased pressure, gas responds by contracting: a gas that"s squeezed into a smaller area like this is more concentrated, so it diffuses more slowly.
