Discussion on the Wearing Method and Requirements of Positive Pressure Fire-fighting Air Respirator

Positive pressure air respirator is a self-contained open air breathing apparatus, widely used in fire, chemical, shipbuilding, petroleum, smelting, storage, laboratory, mining and other departments for firefighters or rescue personnel in smoke, gas, Safe and effective fire extinguishing, emergency rescue and rescue work under various conditions such as steam or oxygen deficiency.

Positive pressure fire air breathing apparatus wearing method and requirements

(I) How to wear

1, pre-wear inspection items

(1) Check full face mask and eyepiece

The rubber parts shall not have obvious permanent deformation; the windows shall be clear; all belts, ropes, and fasteners shall not be subject to aging, cracking, abnormal shrinkage, degumming, brittleness, etc.; and shall be closely fitted to the facial contours according to the mask. The sense of tenderness is obvious, and the fixing system should have enough strength and elasticity, and should be able to adjust according to the wearer's needs, and can perform normal dialogue after wearing.

(2) Checking the backrest and dress belt

Whether the backrest is deformed, deformed but does not affect the use, comfortable to wear, considered as qualified, if there is serious deformation and affect the use or aging, cracking should be considered unqualified. The length of the dress strap can be adjusted freely, and it must not be slipped after being fastened; belt-like parts are not allowed to have breakage of the whole strand of fibre. Plastic and metal fasteners must not be deformed or cracked. Various accessories are complete.

(3) Check air pipes, fittings, air supply valves, pressure reducing valves, alarms, and pressure gauges

The air pipe has no cuts and no aging phenomenon; the connector is not deformed, and the plug lock is easy to remove; the air pipe and connector do not allow air leakage, otherwise it should be replaced or discarded. The gas supply valve and pressure reducer do not allow deformation and cracking, and function keys are clear and effective. There must be no loosening and deformation of the alarm. Pressure gauge shell rubber shield does not allow aging, cracking; pressure dial reading is clearly identifiable, there must be no water fog; dial glass is complete, in a dim or dark environment, should be able to read the pressure indicator value.

(4) Gas cylinders and cylinder valves

Cylinder manufacturing marks and inspection marks are clear and the surface is free from damage. The specific inspections are carried out according to GB24161-2009 "Regular Inspection and Assessment of Composite Gas Cylinders for Respirator".

(5) Performance check

Open the cylinder valve, you will hear the alarm issued a brief cry; After the cylinder valve is fully open, check the gas reservoir gas pressure, generally 28-30MPa, then close the cylinder valve, observe the pressure gauge reading, in Within 1 min, the pressure drop is not more than 2 MPa, indicating that the gas supply piping is high-pressure airtight and intact. Then gently press the supply valve diaphragm to observe the change of the pressure gauge. When the pressure drops to 5-6MPa, the residual gas alarm sounds. If it is less than 80% of the rated pressure, it cannot be used.

When the cylinder pressure is not less than 90% of the nominal pressure, the top cover should be worn to check whether the full face mask is in good conformity with the wearer's face and take 2-3 deep breaths. The air supply is comfortable and the air supply valve should stop gas supply during breath holding. Then press the supply valve switch again by hand to make it in the open or closed state. If the mask does not fit well on the face and leaks, it cannot be used.

2. Wearing requirements

(1) When wearing, first disconnect the quick connector (to prevent damage to the full mask while wearing), then place the back on the back of the human body (the air bottle switch is on the bottom), adjust the shoulder strap and belt according to the figure and fasten it. Fit, secure, and comfortable are appropriate.

(2) Put the long strap on the full cover over the neck, use the full front cover on the chest before use so that it can be worn at any time, and then connect the quick connector.

(3) Set the switch of the air supply valve to the closed position and open the air bottle switch.

(4) Wear a full face mask (without straps) for 2-3 breaths and feel comfortable. When holding gas or exhaling, the supply valve should stop supplying air and there is no "click" sound. Press the lever of the supply valve by hand to check if it is flexible or not. When everything is normal, tighten the full-face straps tightly to the extent that it is necessary to ensure airtightness, comfort, and no obvious tenderness.

(5) After the evacuation site has reached the safe place, loosen the full face strap tie clip and take off the full face cover.

(6) Close the cylinder switch, open the supply valve, unplug the quick connector, and remove the respirator from the body.