Explosion properties, hydrogen, methane

Table 4.12 Combustion and explosion properties of hydrogen, methane, propane and gasoline...

Preeautions also have to be instituted to proteet against the inherent properties of the eylinder eontents, e.g. toxie, eorrosive, flammable (refer to Table 9.1). Most gases are denser than air eommon exeeptions inelude aeetylene, ammonia, helium, hydrogen and methane. Even these may on eseape be mueh eooler than ambient air and therefore slump initially. Eventually the gas will rise and aeeumulate at high levels unless ventilated. Hydrogen and aeetylene, whieh both have very wide flammable limits (Table 6.1), ean form explosive atmospheres in this way. 

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