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1. Measures to prevent gas accumulation

(1) Strengthen ventilation. That is, the intake air flow of the coal mining face does not exceed 0.5%, the return air flow does not exceed 1%, and the total return air flow of the mine does not exceed 0.75%.

(2) Strengthen inspection work. It is an important content of daily gas management to check the ventilation condition and gas concentration of various places in time and deal with hidden dangers when they are found. The methane detection instruments used in China in 1980s include: optical methane detector, thermal methane detector, methane alarm and methane telemetering alarm. Since 1990s, the advanced TX series intelligent portable gas monitor and telemetry instrument have been used.

(3) For coal seams with high gas content, gas drainage should be carried out to reduce gas emission from coal seams and mined-out areas.

2. Measures to prevent gas fire

(1) Open flame is prohibited within 20m around wellhead house, gas drainage station and main ventilation room.

(2) Safety lighting should be adopted in gas mines. It is forbidden to turn on miner's lamps underground, and it is forbidden to carry tobacco and ignition tools underground.

(3) Strictly manage the underground fire area.

(4) Strictly implement the shooting system.

(5) Strictly manage the local ventilator in the heading face, which should be equipped with wind power locking device.

(6) The electrical equipment in the gas mine shall comply with the provisions of the "Coal Mine Safety Regulations" on explosion-proof performance.

(7) With the improvement of mining mechanization, it becomes more and more important to prevent mechanical friction sparks from igniting gas. Gas explosion accidents caused by friction sparks account for a considerable proportion in coal mines, so many countries have studied this problem and put forward that the metal surface of friction parts should be coated with a layer of metal with low activity (such as chromium) so that friction sparks can not ignite gas; The surface of aluminum alloy is coated with various coatings to prevent the occurrence of friction sparks, and a small amount of beryllium is added to the metal to reduce the flammability of friction sparks.

2. Coal mine lines, electrical appliances, pillars, coal winning machines and miner's lamps. Everything used in coal mines should be marked with coal safety signs!

Signs prohibiting fireworks and firecrackers should be posted at the entrance.