If you are considering building an experimental apparatus filled with liquid hydrogen, you might want to keep the following incident in mind:

Deep within the bubble chamber, the inner beryllium window had shattered along a microscopic imperfection in its surface. Splintering outward, the inner window fragments blasted open the outer beryllium window accompanied by the pressure wave of the expanding hydrogen. Within half a second, the laboratory floor was bathed with some 400 liters of turbulent, burning hydrogen. Ignited when the outer window failed, the fire burned wherever the hydrogen and air were mixed. Seconds later, a fierce explosion ripped through the laboratory, strong enough to blow the 31,000 square foot laboratory roof 10 feet into the air. As it crashed back down, roof material cascaded onto the floor and began to burn, raining down hot tar. Now other areas erupted in flames as the soft soldered joints melted in the tubes that linked large quantities of liquid petroleum gas, as well as other combustibles. (Galison, Image & Logic, pp. 356–357.)

Fortunately, it was shortly after 3am, so not many people were around, and only one person died. The most dramatic survival:

One graduate student had managed to crawl into a space between the bubble chamber electronics room and the south wall. Unable to escape further because of his injuries, he remained there until the fire seemed to be closing in. Radioing an ambulance to the east exit, the deputy fire chief, an engineer, a cryogenics expert, and some firemen hacked their way to him and brought him out on a stretcher. (p. 359)

And the end of one eyewitness report:

“I did not consider 80 PSI as extremely serious at that instant since all the peripheral systems are capable of easily handling such a pressure. At this point I turned to check the pressure in the Bubble Chamber to make sure that it was not rising excessively. I never did see the Bubble Chamber pressure gauge.” (p. 356)

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