Anzaniste, Para 1 of BOC reply would seems HSE does have jurisdiction over private matters, if you have a fire with the fire brigade having to attend if it is deemed the incident is due to neglect of HSE regulations I read it as you are responsible.
Acetylene bottles are lethal in a fire situation, a large area has to be evacuated and the bottles have to be cooled for a minimum of 24 hours before anybody can go near them or move them, that should keep you on good terms with the neighbors.
Dick, Not sure on that one, worth looking at, a bottle with a test date from before WW1, I would give that a wide berth.
Tony, does your insurance company insist you stick to HSE guide lines?, I have to contact my insurance company as yet (wish me luck).
Thanks for all your input JD