AL wrote:

Doesn't acetylene combust spontaneously at around 15psi? Can you get 15 psi
by squeezing the baloon?

Can't be. The red line at my acetylen bottle's pressure regulator is at
8 bar (116psi).

Does it have to be in the presence of oxygen?

No, it can disintegrate without O.
And if it is getting into contact with copper, it will ignite earlier.
Brass up to 60% (IIRC) copper is OK.


Nick
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