1. The temperature is too high: when the fire extinguisher is stored in a high temperature environment for a long time, the pressure will gradually rise under the action of thermal expansion and contraction of the gas inside the fire extinguisher.

2. Overinflation: If used improperly, too much compressed gas in the fire extinguisher will also lead to too high pressure.

3. Illegal maintenance: If the fire extinguisher is improperly maintained, the problem of improper gas charging or lax sealing after repair will also make the fire extinguisher pressure too high.

1. Use pressure relief device: Some high pressure fire extinguishers have built-in pressure relief device, when the fire extinguisher pressure is too high, this device will automatically make the fire extinguisher pressure relief. At this time, we only need to put the fire extinguisher in a safe place and wait for the device to relieve pressure, and no other operations are required.

2. The use of vent pressure relief: the vent of the fire extinguisher is used for pressure relief, usually next to the nameplate engraved with the words "pressure relief" or "vent", this position can be found, and the pressure relief rod can be tapped with a hammer a few times, so that the internal pressure can be slowly lowered.

3. Use a pressure reliever: If the fire extinguisher does not have a vent, you can use a pressure reliever to relieve pressure. Connect the fire extinguishing head of the pressure relief device to the nozzle of the fire extinguisher, prepare the bucket next to it, slowly open the switch of the pressure relief device, and turn off the switch of the pressure relief device after the gas in the fire extinguisher is completely discharged.

1. Keep away from fire sources and flammable materials when relieving pressure.
2. Do not puncture the fire extinguisher with a needle or other sharp objects to avoid accidents.
3. Do not discard the fire extinguisher after pressure relief, and send it to the relevant departments for maintenance and filling.