Firedamp

Firedamp firedamp or are in the underground mining industry - particularly in the coal mining industry, but also in the salt and ore mining - leaking underground coal mine gas (methane ), which can react explosively with air in the mixture.

Such a firedamp explosion in coal mines often precursors and triggers a coal dust explosion with even much greater destructive power.

Background

As the weather Bergmann mean all located in a building pit gases (see also Bergmann language ).

Methane is the most dangerous when used in the air a proportion of 5 to 15% has. Already a spark may be sufficient to ignite this mixture.

Prevention measures

Located in the historic mining

In the 19th century, many innovations were introduced to prevent firedamp explosions. So was prescribed gradually prohibited by the use of the open Geleuchts and safety lamps compelling, many devices underground were operated by compressed air, the usual line-up of steam engines underground and also the use of Wetteröfen prohibited until then to eliminate sparking. Only since the twenties of the 20th century, electric current is used as an energy source, since it was able to produce flame- proof electrical equipment and Geleuchte increasingly.

In earlier times, the miners took birds (eg canaries ) as a gas with Warner in the pit. The crystals were from toxic gases, but hardly warn of flammable gases. On the occasion of the accident on the Radbod (348 deaths) were from the 1908 electric mining lamps systematically introduced in Oberbergamt district Dortmund to reduce the risk of explosion.

Today's measures

To prevent firedamp explosions, there are now strict regulations, compliance with which is monitored by a competent for ventilation Steiger, the weather Steiger.

With the help of water trough barriers ( 80 liters) or line trough barriers or rock dust barriers, the extent of a firedamp explosion be contained because it followed a coal dust explosion is prevented. These are open-ended, water-filled troughs or with marble powder behäufte boards that are mounted under the hanging wall of the track. In an explosion, the containers are thrown down or destroyed by the blast and the subsequent flame front is cleared by the atomized in the air water or the rock dust.

An example of further measures is the pressure wave sealing.