How to Use the Gas Detector to Prevent Hydrogen Explosion?

Hydrogen is the lightest gas already discovered in the world, which is colorless, smell-less, non-toxic, inflammable and explosive. Its density is very small, which is just around one fourteenth of the air. If mixed with Fl, Cl, O2, CO and other gases in the air, it might cause explosion. Meanwhile, the mixture between hydrogen and fluorine might cause spontaneous explosion under a low temperature and dark environment. When mixed with Cl at 1:1, explosion might be triggered under exposure to the sunlight. The gas is lighter than the air, stored and used in the indoor environment. If the leakage rises to the roof, it is hard for the gas to discharge, thus causing explosion in contact with sparks. Industrially, hydrogen is mainly used as a reducing agent and is widely applied to petroleum refining, float glass, electronics, food, and chemical production, aerospace and automobiles. Under general conditions, hydrogen is stored in the liquid state. If the liquid hydrogen overspills and evaporates by a large area, oxygen deficiency might be caused, and might be mixed with the air to form the explosive mixture and to cause combustion explosion.

ATO technicians suggest that, when combustible gases are stored in a closed or semi-closed plant, one detector might be set up at an interval of 15m. Meanwhile, the detector should not be apart from any release source by longer than 7.5mm. The toxic gas detector should not be put away from the release source by longer than 1m. The combustible gas release source, which is lighter than the air, should be put in the closed or semi-closed plant. The detector should be put above the release source, or the highest point where the combustible gas can easily accumulate.

When the hydrogen gas detector is applied to production safety, real-time monitoring should be conducted in accordance with production safety. Once the gas leakage occurs, the corresponding measures should be adopted. Personnel should be evacuated, and the leakage polluted area should be moved to the upwind position and the polluted area should be isolated to strictly limit entry and exit. Cut off all kinds of fire sources and leakage sources.

Ensure reasonable ventilation to accelerate diffusion. It is suggested that the emergency personnel should wear the positive-pressure air respirator and wear the fire-fighting protection suite. If possible, discharge the hydrogen leaked out using the exhaust fan to the empty space or install it with the shower nozzle to burn it out. Below are two methods to put off the fire: 1. Cut off the air source. If the gas source cannot be immediately cut off, the gas which is still burning should not be extinguished. 2. Spray the water to cool down the vessel. If possible, move the vessel from the fire ground to the open space, and make use of the spray water, bubble and CO2 dry powder for extinguishment.