It is not AIR that causes the swelling, there is plenty of info out there that will scare you out of doing something arguably reckless like I did. Give this thread a read for example-http://www.rcgroups.com/forums/showthread.php?t=1258876
From that thread-"Actually, the gas will be Hydrogen, and possibly some amounts of Hydrogen Flouride, which is very nasty stuff. Hydrogen gas is flammable. Hydrogen Flouride gas is not, but it reacts with moisture (say on your skin) to form Hydroflouric Acid, which is about as bad as it comes."
Also-"Did you know that when outgassing it can develop a static charge which will create a "torch" flame."
From that thread-"Actually, the gas will be Hydrogen, and possibly some amounts of Hydrogen Flouride, which is very nasty stuff. Hydrogen gas is flammable. Hydrogen Flouride gas is not, but it reacts with moisture (say on your skin) to form Hydroflouric Acid, which is about as bad as it comes."
Also-"Did you know that when outgassing it can develop a static charge which will create a "torch" flame."
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