i've seen an air hose end tear open, leaving the metal quick-disconnect still partly attached. that hose only delivered 90 psi. while the hose was flying around like crazy, it hit a few cars in the shop and dented doors and fenders - lucky it didn't bust any windows. everyone got the hell away from it because with that chunk of metal on the end (quick-disconnect) it could really have hurt someone. thankfully there was a main shutoff valve right on the output of the compressor, after the drier, so we only had to wait for the air in the pipes and other hoses to run out before the hose fell back down. if it hadn't been there, we would have had to wait for ~500 gallons of compressed air to blow out.