What do you mean by ventilation and three defenses?

One ventilation and three prevention means ventilation, dust prevention, gas prevention and fire prevention. One is mine ventilation, and the other is to prevent gas, coal dust and mine fires.

Gas is a colorless, odorless and tasteless gas, with a relative density of 0.55 with air, insoluble in water and nontoxic. When the concentration is high, it will lead to suffocation and death. It is necessary to cut off the power supply, evacuate people and stop other work in the return air system to discharge gas.

Before gas discharge, the person in charge of the site should arrange the safety officer, the shift leader of ZuoYeDui and the number of people in the dry counting working face to evacuate, and set a warning at the entrance of the area where gas discharge may flow to prevent people from entering by mistake.

Measures to strengthen gas detection:

1, the gas and carbon dioxide in all mining faces and retreating faces shall be checked at least three times per shift, and the gas and carbon dioxide in tunneling faces with gas emission greater than 1m3/min and coal mining faces with gas emission greater than 3m3/min must be checked by designated personnel at any time. Check the gas and carbon dioxide content of the mining face and the non-production installation face at least twice per shift.

2, the gas inspector must use optical tile detector to check the gas, and carry not less than 2m hose and inspection rod, must check whether the instrument is in good condition before entering the well. The gas inspector shifts in the designated place underground, and records can be found; No empty shift missed inspection, no false report of gas.

3. The gas inspector must check the gas according to the inspection route, inspection location, inspection time and inspection times indicated in the inspection map, and report the ventilation scheduling immediately if the gas exceeds the limit.