Remember the Pi mark is the 'gate' Pi symbol and not the word Pi
(On occasion people have thought they ended up with a US bottle because of US in the markings.
Historically (circa 5 or more years ago) when I began people were bringing scuba bottles to fill, partly because sites only had co2 and partly so they would be let alone to fill their own US DOT bottles.
UKPSF sites will all check your bottle, and any site worth it's salt will check.
Remember that hydro tests are a safety check in the same way as an mot for cars. Neither of them reflect the condition today, only the condition at the time of testing. You would not drive a car with no mot, you do not know how the bottle has been handled before it came to you, you only know it was up to a standard when it was made. This is probably a bit over dramatic, and you can get a reasonable idea from the condition or any marks. (Damage to the fibre is an instant fail anyway). But worse things have happened - since my early days we have had many scares with people blowing burst disks at the wrong fill station and a couple of genuine bottle explosions in Europe - one around here down south.
People have learned real lessons, safe processes put in place and awareness publicised
a test is easy, and also much cheaper then buying scuba and / or evading bottle checks
You just need a test run at any IDEST centre
http://www.sita.org.uk/idest/idest_members.php
And check out the UKPSF HPA 1 for air safety
http://www.oaklandsfestival.host56.com/web_documents/air information.pdf
if I fill myself with a dive tank, can I still use it at sites? I suspect not I just want to check before I write it off!
