World Surveillance Group Inc (fka WSGI)

[trunkmonk]

you most likely leak tested it with helium because it was an inert gas as well as its atomic weight. I dont think OSHA would have approved leak testing an oven with hydrogen or anything other than an inert gas. almost all leak testing is done with helium, its inert, its 100% safe, its small, its easy to get out of the ground since it mingles with natural gas. diatomic or not, pliable material is always an escape route for gas especially when atmospheric pressure is working against you. taking up small compressed gas modules with a regulator is the best way to keep anything up in the air longer.