[trhway]

a party balloon - say a cubic foot - is about 2g of hydrogen. Involves 16g of oxygen. So we're talking 18g of very fast burning, borderline detonating mass. Releases 240 KJ of energy. To compare the hand grenade - 60g TNT https://en.wikipedia.org/wiki/F-1_grenade_(Russia) - releases the same 240 KJ of energy.