1. Briefly describe how to use an air respirator?

1. Wear a respirator 1.1 Take the respirator out of the packaging box and check the integrity of the system； 1.2 Check the cylinder pressure by observing the reading on the pressure gauge on the cylinder valve. If it is equipped with a bottle valve that does not have a self-locking function, open the bottle valve and check the reading on the high-pressure gauge on the breathing apparatus ； 1.3 Bring the gas cylinder close to yourself on a flat surface, with the side of the cylinder that has the pressure gauge facing outward. Place the shoulder straps of the harness between your hands, hold the handles on either side of the back panel with your hands, lift the respirator above your head, then bend your arms backward and downward to lower the respirator so that the shoulder straps rest on your shoulders. 1.4 Pull down the shoulder straps to bring the respirator to an appropriate height; it doesn’t need to be set too high – just make sure it’s comfortable to wear ； 1.5 Insert the chest strap. Fasten the belt and pull it forward to adjust the tightness to the proper level. 22. Check the alarm performance of the alarm whistle. 2.1 Ensure that the air supply valve is closed ； 2.2 Turn the cylinder valve open by about half a turn, observe the pressure gauge, and then close the cylinder valve once the pressure stabilizes (Figure 8) ； 2.3 Alarm performance check: Use the palm of the left hand to block the outlet of the air supply valve, leaving a small gap; with the right hand, gently press the exhaust button on the air supply valve to allow air to escape slowly. Observe the changes in pressure on the gauge. When the pressure drops to around 6.5 MP, reduce the amount of air being exhausted. Keep an eye on the pressure gauge as well as the sound of the alarm whistle, which should start sounding at a pressure of 5.5 ± 0.5 MP ； 2.4 After checking the alarm function, turn the gas cylinder valve at least two full turns. 33. Wear the mask and check its airtightness 3.1 Take out the mask and loosen the head strap of the mask ； 3.2 Hang the mask’s neck strap around your neck ； 3.3 Put on the mask, placing the chin in the chin rest of the mask ； 3.4 Pull up the headband so that its center is located at the center of the head ； 3.5 Tighten the lower two head straps to an appropriate tightness, making sure to pull them in a backward direction ； 3.6 Tighten the two middle head straps to an appropriate tightness ； 3.7 Tighten one of the upper headbands to an appropriate tightness ； 3.8 Check the airtightness of the fit: Cover the air inlet of the mask with the palm of your hand, take a deep breath. If you feel the mask pressing against your face and no airflow is detected inside the mask, it indicates that the mask is sealed to your face. 44. Connect the air supply valve and enter the work site. 4.1 Align the air outlet of the air supply valve with the air inlet of the mask and insert it into the mask; a slight clicking sound indicates that the air supply valve and the mask are properly connected ； 4.2 Take a deep breath and open the air supply valve ； 4.3 Breathe a few times; if there is no discomfort, you can enter the workplace ； 4.4 Pay attention to the changes in the pressure gauge during operation; if the pressure drops to the point where the alarm whistle sounds, it is necessary to retreat to a safe location immediately. 55. Removing the respirator 5.1 Return to a safe location after completing the work ； 5.2 Disconnect the air supply valve: Take a breath and hold it, then press the red button on the air supply valve to close it. Hold the valve with your right hand, with the valve body in the palm of your hand; use your thumb, index finger, and middle finger to grip the handle of the air supply cylinder and turn it slightly, thereby pulling the air supply valve away from the mask. 5.3 Remove the mask: Use your index finger to pull the stainless steel clasp on the mask’s head strap outward to loosen it, then grasp the air inlet on the mask and pull it away to remove the mask; place it aside properly. 5.4 Removing the respirator: Insert the thumb into the buckle and pull outward to disengage the plug from the buckle ； Unfasten the chest strap buckle ； Pull the clasp on the shoulder strap outward to release it ； Grab the shoulder straps and remove the respirator. 5.5 Close the gas cylinder valve. 5.6 Press the green button on the protective cover of the gas supply valve to release any remaining gas in the system; otherwise, the gas cylinder and regulator cannot be disconnected. 66. Disassembly and Installation of Gas Cylinders 6.1 Disassembly of the gas cylinder: 6.1.1 Check the pressure gauge to ensure there is no pressure in the system. 6.1.2 Use the wrench on the gas cylinder strap to loosen it. 6.1.3 Rotate the handwheel on the regulator to disconnect the gas cylinder. 6.2 Installation of the gas cylinder: 6.2.1 Insert the gas cylinder into the strap on the backplate. 6.2.2 Ensure that both the gas cylinder and the backplate are vertical. 6.2.3 Align the center of the gas cylinder valve outlet with the center of the regulator’s handwheel. 6.2.4 Rotate the handwheel to connect the regulator to the gas cylinder

1. Inspection: Check for any damage to the mask, examine the quality of the tubing, check the pressure in the gas cylinder (it should be no less than 25 MPa), and check the low-pressure alarm (the alarm will sound when the pressure drops below 5 MPa). 2. Putting it on: (1) Attach the cylinder carrying the air supply to your back, and tighten the straps and shoulder belts. (2) Hang the mask around your neck, put it on, tighten it, and then cover the air inlet with your hand to check for a seal. (3) Open the cylinder and connect its tubing to the mask.

The second floor part was copied and pasted, the third floor part was summarized by myself; I could tell

Usage: (1) Open the gas cylinder valve, check the pressure inside the cylinder (the pressure should be at least 24 MPa), then close the valve to release any remaining gas. 　　(2) With the cylinder valve and back support facing upward, wear the respirator over the shoulder or in a cross-style, and adjust the position and tightness of the shoulder straps until it feels comfortable. 　　(3) Insert the belt plug, then pull the elastic band on one side of the belt back and fasten it securely. 　　(4) Open the head mesh of the mask, put the mask on the head from top to bottom, and adjust its position. Press the mask’s air inlet with your hand and check the seal of the mask by taking a breath; if the seal is poor, tighten the mask’s straps or put on the mask again. 　　(5) Open the gas cylinder valve and supply valve. 　　(6) Align the air supply valve interface with the mask interface, then hold the inhalation portion of the mask; use the left hand to press the air supply valve inward. Once a \"click\" sound is heard, the installation is complete. 　　(7) Breathe several times to check the performance of the air supply valve. Both inhalation and exhalation should be smooth, without any discomfort.

What was said above is too complicated: 1. Put on the air respirator, 2. Open the cylinder valve. That’s all there is to it