Ah now that's not quite so easy. If I'd asked you what gun or barrel you use then you could tell me without thinking twice. But asked what kind of bottle you use I'm sure 95% of you wouldn't have a clue. Yeah, you might know what size, but I'm talking about what make. OK, so you've been and taken a look at what make it is, but before you stick it back in your bag and forget about it just take a quick look and see if it's out of test. Happy? Oh, and before I forget, could you check to see that it has the correct safety standard stamp for the country you just happen to be using it in. Great. I'm glad to see that your bottle checks out alright. Unfortunately that guy there next to you trying to get 4500 P.S.l. into a circa 1901 20oz 002 tank isn't quite so sure about things. And there are thousands of bottles being used every weekend that aren't quite so politically correct as yours. It may sound picky, a bit melodramatic even, but if either of the above criteria are not fulfilled by a tank, then the very use of that bottle is against the law. The sad case is that it's quite common for people to be using out of date and incorrectly certified bottles all over the world. It is not through any malicious or subversive intent that these bottles are being used, but more through lack of education or mis-information.

AS (I hope) was illustrated in the first part of the article, most people aren't aware of what the potentially explosive devise tucked under their arm is, or the criteria that need to be fulfilled for it to be filled and used correctly and completely legally. What is even more worrying is the fact that it would appear that nobody, including myself, knows the full legal and safety implications of the massive misuse of compressed gas cylinders within Paintball. This article is not to be taken as some kind of witch hunt, but is designed to make players aware of a situation that could be very damaging to Paintball in the future. So let's go back to the beginning. This aspect of Paintball safety is one that, until last week when I was contacted by Luxfer Gas Cylinders, I had never given that much thought to. I knew that bottles in the States had to be tested to D.O.T. standard and to B.S. standard in the UK, and that was about it. The fact that filling a D.O.T. 2Ooz bottle during the everyday course of my work was actually illegal had never even occurred to me. That, you see, is the problem. Because of the way that Paintball works, with individuals and small operators decanting from larger, easily accessible and regulated cylinders into the smaller Paintball cylinders, the established lines of defence and prevention of incorrect filling procedures are breached. Where it is known to be illegal (and hence heavily monitored) by big gas supplying companies such as B.O.C. and Air Products to refill unregulated and out of test cylinders, that responsibility is passed on to the next person that decants from their bottles to ensure they are not acting illegally and unsafely. And with this responsibility now in the hands of people who are not so well educated or regulated or, as is more common, who don't actually care, this established system is open to abuse.

FROM all this talk of different standards of bottles it would be easy to assume all the bottles are made to different designs and specifications. Actually, this is not at all true. On my trip around the Luxter small cylinder manufacturing plant in sunny Birmingham, England, it was quite surprising to see literally thousands of Paintball 002 cylinders rolling off the production line. And they were going all over the world. There was no physical difference between any of the bottles right up to the very last section of the line where, at the place the D.O.T. bottles were inspected, tested and stamped, sat a big ol' yank guy in a long white coat. And where the B.S. ones came off sat a skinny little Brit. What these guys do is, well, not very much but get paid loads of cash and get to stay in posh hotels all the time. Seriously, they are there to ensure that during every stage of the manufacture and testing of the bottles by Luxfer, the guidelines set down by their respective departments for health and safety as to how those bottles should be made are followed. Once they are satisfied that everything has been done to the letter, they allow the cylinders to carry the official designations of safe manufacture of their respective countries. Now I've probably been a bit misleading again, letting you think that there is only really US and UK standards. Wrong.

Every single country has their own individual safety standards. Obviously, it's a nightmare every time Luxter need to manufacture a bottle for any country, there has to be a representative present from that country to oversee manufacture. And you guessed it, they have to pay for that privilege. As with everything that "has" to be done, it costs an arm and a leg. In fact it is quite a significant part of the cost of the whole manufacturing process, which as always means a higher price to the end user. It is not just that little guy having to stand there, but also that every single bottle is both visually and hydrostatically tested. Every single one. There is very little that is made these days where 100% of the manufactured products are tested, but this is one of them. Each tank is tested to withstand one and a half times its safe working pressure. That's called its Test Pressure. Out of those, 1% are tested to Burst pressure, commonly two and a half times its test pressure. That's a lot of pressure.

YOU would have thought that having gone to all that trouble of having all those tanks carefully inspected and tested, the end user, yes you, would know why they have been made. However, people don't know and that is where the danger starts. There are three different pressure ranges that tanks are made and commonly used for:

1800 P.S.I. Most commonly used for 002. Only aluminium, cold extruded, seamless bottles used today. In the old days we had heavy steel tanks, but they were few and far between. Working pressure typically 1800 P.S.I. This means they are also suitable for medium pressure compressed air, filled to 1800 P.S.I. These tanks can be found in a vast array of sizes including the more common 3 1/2, 7,12 and 20 oz.

3000 P.S.I. Most common pressure for compressed air/nitrogen. Aluminium, Hoop wrapped and full Fibre(glass) wraps are used in this pressure range. All the tanks have a W.P. of 3000 P.S.I. (207 BAR) and T.P. of 4500 P.S.I. (310 BAR). The real difference comes down to performance, which is index-linked to the amount of cash you've got. Basically speaking, the more cash you spend, the lighter your bottle becomes. One of those strange anomalies where you end up paying more for less. Again these come in a range of sizes including 63 cu. in. (1.1 Ltr.)and ll4cu. in. (1.9 Ltr)

4500 P.S.I. This is a relatively new area for the Paintball market and has grown vastly in the US. It has yet to take off in Europe due to the unavailability of high pressure large tanks to decant from. Bottles are generally the most up to date Carbon fibre fully wrapped type. W.P. of 4500 P.S.I. with T.P. of 6750 P.S.I. It's really down to the place you purchase your tank from to ensure that you are going to use it for the application it was intended for, but it is finally your responsibility that you use it and fill it correctly at all times. If you are in the least bit unsure, it is always better to be safe than sorry. Contact your local shop and ask for help and if you don't think their advice is right or their explanation too clear, you can always contact me here at PGI. Be Safe!

Facts 'n' Figures

Decanting
This is the process used to refill empty or partially full tanks. Using what is normally called a Fill Station, the tank to be filled is connected to the larger storage tank. Air or C02 is then transferred from the storage tank into your bottle. For the transfer of air or C02 to take place, the tank you are filling from must be at a higher pressure than the one you are trying to fill.

Fills
The measurement of gas in a tank is dependent on the type of gas. C02 is always calculated by weight, never by pressure. A 20oz tank is designed to carry safely a maximum of 20oz of C02. A pressure gauge on a C02 bottle can never tell you how full it is. The pressure in the tank is connected to the temperature of the C02. Air, on the other hand, is measured as a pressure within a fixed volume. The volume of the tank is irrelevant to the pressure you can fill it to. The maximum fill pressure is always its safe working pressure, printed on the bottle.

Abbreviations
W.P. =working pressure(or fill pressure). This is the maximum any bottle should be filled to and should be printed on the bottle. T.P. =test pressure. The pressure the bottle is hydrostatically tested to. You should never try to fill to this pressure. Any burst disks must fail before this pressure. B.P. = burst pressure. The pressure at which the cylinder will explode.

Jack Wood

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