Very dangerous, glad no one was hurt.
Careful with anything that uses a compressor. HSE has recently been around our estate targeting all compressor users. Making them get everything pressure tested - cylinder, piston, pipes and airlines as well as the tools and machinery all had to be tested. One of my neighbours had to pay about £1500 for testing and a further £600 fees to HSE ( they charge £128+vat per hour 'fee for intervention'). It is only a matter of time before they realise that print shops and screenprinters often use compressors, and we become their next 'cash cow'.