One of the foremost problems that have confronted the miner in the winning of coal is the dangerous nature of gas. Ventilation of an underground coal mine became a necessary and often expensive operation.

Mine ventilation is twofold in purpose: first, it maintains life, and secondly it carries off dangerous gases. Long before coal was mined in North America, collieries in Europe were sunk with dual entrances; one through which air flowed into the mine and another through which air flowed out. Initially, mine ventilation was assisted by underground furnaces, which used the practical principle that the updraft of a fire caused a suction which drew air out of the mine and this air was replaced by air which was pulled in to fill the opening. The presence of gas is always trouble in a mine. Methane gas or Marsh Gas, in concentrations of 1.25 percent or over, can cause a powerful underground explosion; especially if accompanied by a high concentration of coal dust. Other gases often present in a coal mine are: carbon monoxide and hydrogen sulphide. The presence of these gases necessitated that proper ventilation be assured in any underground workings.

Canaries are said to have been used to detect gas in coal mines in the early stages of coal mining. This sensitive bird would be taken into the workings and, if it perished, the colliers would immediately leave the mine. However, before the 1870s, managers and qualified persons were using safety lamps to detect gas. These safety lamps soon replaced oil lamps and open flared candles as a source of working light.

Soon, small hand-turned fans were used to blow out gas from working places into main air currents. Trap doors were strategically placed as part of the ventilation system to guide the flow of air to or from selected areas. "Trapper" boys were posted at the busier doors to open them for the passage of coal, materials and men. "Air courses" were frequently cut through coal and rock.

In the 1920s the hand-turned fans were replaced with air-powered small turbine fans. Large fans of the suction type were placed on the surface and gradually increased in size. Air from surface compressors was piped into the mine to power machinery and to assist in ventilation.

In areas with no return air course, a thick ply canvas called "brattice" was used. This measure was usually temporary; it involved canvas draped from the roof to the mine floor, dividing the affected section longitudinally, permitting air to flow in on one side and flow out the other.

Brattice is often used in rescue work to carry ventilation from the last proven air point, to the limit of rescue operations.

Considerable progress has been made towards improved ventilation by employing better systems and better means of gas detection. Now, each operating long wall is equipped with a continuous recording methanometer that records and displays the concentration of methane in the air in which its sensing head is cited.

A signal is transmitted at 15-second intervals over a communication system on the wall and to other strategic locations underground and in the mine manager's office, where an audible "beep" indicates the system is operating. Other facilities included are: