I hope the point I'm trying to make here is clear because it's easy to misunderstand what my real concerns are without the 'safety' smokescreen smothering the topic but here goes...

I have a small 3 litre 300 bar Bisley stumpy bottle. I bought brand-new and have only used it as a backup supply to a 12 litre Faber. In fact, the bottle had only ever been filled twice, once when new and then topped up about 18 months ago and both times at the dive centre mentioned below (so clean / dry air). The 3 litre Bisley has just reached the end of it's 5 years and so I dropped it off at a well known local dive centre for hydrostatic test, valve test, service and fill. When I dropped it off, a nice chap (one of the testers) seemed to have all the time in the world to explain all the horrors he'd seen and heard about involving dive bottle misuse and unsafe practices and the horrific results.

After about 15 mins (yes 15 minutes), he finished off by saying that should there be any problems with the bottle then they were not allowed to hand it back for obvious reasons, i.e. unsafe, potential bomb etc. unless all necessary work / parts replacements were agreed to and carried out. I pointed out that the bottle had seen very little use and that on the very rare occasions of it being used, I always attached only ever attached the whip using hand pressure as I found this was always sufficient enough.

A week goes by and while at work, I receive a voicemail from the dive / test centre. Apparently, the bottle was fine but the valve failed. I didn't fully understand why it had failed but they mentioned a 'no go gauge' turning four times instead of only two. I called them the next morning and asked for them to clarify the problem and they put me through to the tester. He explained that the threads that you screw in the whip failed the 'Go - No Go' gauge test. A replacement valve would be an additional £61.00 bringing the total cost of certification to just over £100.00.

I asked his opinion on what causes the treads to fail the test and he immediately mentioned over tightening as the main cause in most cases. I again explained that I only ever used hand pressure to attached / tighten the whip to he valve and his response was that the threads are only brass (soft) and that the threads may well have been overtightened previous to my ownership. I explained I had owned the bottle from new and so I could not be the case. The tester then said that it may have been faulty from new and that Bisley import these bottles (not sure what significance this has).

I know of another dive / test centre local to me and I thought it would be worth getting a second opinion, so I asked if I could collect the bottle and I was informed that this was not allowed and that if the necessary replacements were not authorised they would have to scrap the bottle and valve.

Now call me cynical but how on earth are you supposed to know that these 'necessary' parts are really needed and if the threads are faulty how can you avoid this type of wear given what little and very light use the bottle has had. If the threads were faulty when new, then how did it pass initially?

It may be that the threads have failed and that the new valve is needed but I can't help but feel they know there's nothing you can do but pay or else!

Thoughts anyone?