In my youth, I worked as an Equipmnt Engineer in the nuclear industry. We designed, installed and maintained custom equipment used to manufacture nuclear fuel. Mostly high temperature furnaces. I had hydrogen, oxygen and a dozen other flammable gasses plumbed all over the factory. The part I remember about hydrogen is when the process chemist would come by and run the raw gas up a two story tall furnace to calibrate his flowmeters. We always told him to heat up the furnace first to assure controlled combustion. He was always in a hurry. Cold furnace. Release cold hydrogen into the furnace exhaust duct. Hydrogen finds it's critical air fuel ratio inside the duct. BANG (BIG TIME!), auto ignition. No spark plug needed. He collapsed the three foot ducts on at least two occasions before he got the message.
Now if hydrogen will auto ignite (think very rapid burning, called an explosion)in the mere presence of air, I'm gonna be real leery about just being near anyone driving a homebuilt hydrogen generator. Ever hear of a battery exploding? Same stuff. Also, Hydrogen is the smallest gas molecule in capitivity. Most gas tight fittings would leak hydrogen like a sieve. Just because the technology is there, doesn't mean we can all go build a fuel cell in the back yard. think i'll sit this one out.
