Under the coal mine when the fire broke out, on the one hand to protect the safety of mine workers, on the other hand to take certain ventilation measures to control air flow, it does not allow airflow reversal caused by fire or smoke filled the roadway and roadway gas harmful gas poisoning occurred explosion.

(1) Measures to ensure the safety of personnel

1. Measures to evacuate personnel from dangerous areas

In the event of a fire, the area directly threatened is the area through which the fire zone and its adjacent areas and the fire smoke flow to the wind well. Therefore, those working in these areas and on the wind road should be withdrawn first, in addition to participating in disaster relief. In addition, people who are likely to have a reversal of the wind and are exposed to fire and smoke should also withdraw. When preparing fire prevention measures and formulating plans for disaster prevention measures, it is necessary to take into account the shortest and safest route to evacuate the victims and the people at risk when a fire occurs anywhere in the underground, and send them a method of alerting them to them. Measures for safe locations, etc. The disaster prevention plan must be implemented carefully among employees to let them know the content of the plan.

The route to evacuate should be well maintained, properly lit, and marked with the name of the lane and the signpost leading to the exit or refuge. Usually underground personnel should be familiar with these routes (including when they change).

Existing rescue doors can be used when rescuing people who are threatened by smoke from fresh airflow. Closing the fire door can greatly reduce the fire and smoke flowing to the corresponding area. However, fire zone fire doors in the airstream without fire smoke should not be closed.

In areas where fires are everywhere, if there are still people who have not withdrawn or if they have not come out, they must not interrupt the ventilation of the area.

2. Safety protection measures for disaster relief personnel

In the case of reversal of possible winds, we should do our best to observe this aspect. Before the fire is controlled, the relevant responsible personnel should attach great importance to it, discover the signs in time, and take safety measures.

The most dangerous period of explosion of fire smoke is when the main closed wall is built. Therefore, in order to avoid the adverse consequences of the explosion, it is best to make the trunk closed wall into a form with a door. After closing the door, you should leave the closed wall and its vicinity as soon as possible. If there is no explosion after a certain period of time (such as 3h to 4h), return to the closed wall and start the corresponding tightening and reinforcement work. However, it should still be completed as soon as possible, especially in gas mines.

After the establishment of the main closed wall and the stabilization of the established direction of the wind, it can be said that the fire has been basically controlled. It is then possible to proceed with the establishment of the last as tight a fire-extinguishing wall as possible (if it is decided to use an isolation method to extinguish the fire). The permanent closed wall of the exhaust should not be urgently sealed, and the exhaust pipe should be left. The exhaust pipe is also used as an observation hole for the fire zone. Only after a certain period of time, when the gushing smoke has been greatly reduced and there is a huge positive pressure phenomenon in the fire zone, the exhaust wall can be completely closed. Because, when there is a large positive pressure phenomenon, the fire smoke in the fire area will even flow outward from the closed wall of the human wind side. In the early stage of the fire, the fire smoke will certainly contain a lot of toxic and harmful gases, which will cause poisoning of the atmosphere inside the mine. .

All roads that lead to dangerous areas should have warning signs.

During the fire fighting process, the mineral composition of the mine should also be continuously checked and the results reported to the firefighting commander at any time. When gas reaches dangerous concentrations, personnel should be decisively and immediately ventilated to ensure the absolute safety of the firefighters. In addition to the instruments that the inspectors carry with them, each mine should have a gas laboratory.

(2) Measures to control the wind flow

1. Ventilation method when dealing with fire

When a fire occurs in a well, the common ventilation methods are: normal ventilation, increase or decrease of air volume, reverse wind, short circuit of wind flow, isolation of wind flow, and stop fan fan operation.

2. Select the ventilation method according to the location of the mine fire

(1) If the fire occurs in the inlet shaft of the mine, the bottom of the well, etc., the toxic and harmful gases generated by the catastrophe will invade the mining areas with the wind flow, threatening the life safety of the workers in the underground mine. At this time, we must take anti-wind measures. In order to meet this requirement, each mine must:

1 The mine must have reliable anti-wind facilities, and can change the direction of wind flow within 10 minutes. The air supply of the main fan after the wind is not less than 60% of the normal air volume.

â‘¡ isolated main return air inlet passage damper, use is made of iron plate, when the bidirectional switch, to ensure that the anti-wind tunnel can be reverse flow in the airflow.

3 The anti-wind facilities shall be inspected regularly in accordance with the provisions of the “Safety Regulations for Coal Mines” and regular anti-wind exercises.

4 If the main ventilator has no anti-wind facilities, maintain a short-circuit channel connecting the main inlet and return air areas in the daily ventilation management, so that the toxic gas bypasses the mining area and directly exits the return air passage during the sudden change. The main fan should remain in normal operation.

5 If there is no anti-winding facility and no short-circuitway, the auxiliary fan and main fan should be stopped as soon as possible, and the explosion-proof cover of the wellhead should be opened to achieve the anti-wind by the local fire pressure generated in the inlet wellbore.

(2) If the fire occurs in the upwind road of the mining area, the safety of the centralized working place is not threatened on the road that exhausts the smoke, and the main fan should be kept in normal operation.

(3) If the fire occurs in the electromechanical diverticulum, measures to block the wind flow should be taken, and the wind barrier should be installed in the wind or the temporary opening of the chamber.

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