DOSEEM Cylinder Inflation & Maintenance

Air composition:

The air used for the respirator should be natural or synthetic air that meets the health requirements. Typical natural air (water content in the air should not exceed 30mg/m3). The composition is as follows:


Component name

Constituent ratio (%)

















  • The cylinders should be filled with clean, dry air that meets the human respiratory requirements and must not be filled with any other gas or liquid. Humid air or other gases will corrode the cylinder liner;

  • When inflating, protective measures should be taken to ensure that the inflatable joint is reliably connected to the gas cylinder, slowly opening the gas cylinder valve to inflate the gas cylinder;

  • The cylinder valve and the inflatable valve are closed, the residual pressure in the inflatable pipeline is emptied, then the cylinder is removed from the inflator, and the leakage agent (4 water and 1 liquid detergents) is applied to the leak detection of the bottle mouth and the cylinder.

  • Gas cylinders that have been inflated and filled should be marked with “inflated” and properly placed on special racks or on back rests.

Inflation precautions:

  • Gas cylinder inflation should be performed by trained qualified personnel. Inflatable sites should be carried out in designated departments;

  • The rated working pressure of the gas in the cylinder is 30 MPa. When the high-pressure gas is inflated, the temperature of the gas cylinder will rise. The cylinder should be naturally cooled to room temperature and then replenished to the rated working pressure (the cylinder must not be soaked in cold water to cool). The cylinder pressure is normal between 25~30MPa;

  • Do not immerse the cylinder in water to detect leaks;

  • Do not store gas cylinders near heat sources or in direct sunlight to avoid accidents.


  • After use, the cylinder should be wiped clean with a soft cloth and labelled to indicate the identity of the empty bottle for timely inflation. The gas cylinders that are filled with gas are fixedly connected according to the assembly position so that they can be used at any time;

  • Visual inspection of the cylinder last test date, whether it has expired, check the surface for dents, scratches, burning hot flames, rust and other phenomena, whether the bottle is damaged, the cylinder valve switch is flexible;

  • When installing or removing gas cylinders, the threaded joints of the cylinder valves must be protected. Rigid objects must not be tapped on the threaded teeth so as not to damage the threads. Cylinder bottle mouth is prohibited from contaminating grease.


  • All the gas in the cylinder is completely vented after the safety protection diaphragm is blasted. If the safety diaphragm blasting should check the reason, and replace the qualified special diaphragm in time, must not use other substitutes to replace the special diaphragm;

  • When using or inflating the gas cylinders, handle them gently and do not collide with them. Sudden release of high-pressure compressed air is very dangerous. Be careful to store it;

  • Gas cylinders shall comply with the requirements of the “Cylinder Safety Inspection Regulations” of the National Bureau of Quality and Technical Supervision (Qualitary and Technical Supervision Bureau of State Development [2001] No. 250). According to regulations, steel cylinders should be tested at least once every three years and carbon steel cylinders should be tested at least once every five years. Detection of damage, corrosion or other problems that may affect safety use should be checked ahead of schedule.

  • If you find that the cylinder exceeds the inspection cycle or is damaged, do not inflate it. If there is compressed air in the cylinder, please empty the air. After re-testing, you can inflate it. Otherwise, safety accidents may occur;

  • After the cylinder is used, a certain pressure should be kept to prevent toxic gas or moist air from entering the bottle;

  • Equipment must be inspected at regular intervals, and always after use in practice or in an emergency. It should never be stowed when wet or dirty.