We have all been there, or will be at some point in our dive lives. While hooking up our gear, you’re getting excited for the dive, going over every piece of equipment to make sure it’s just as we like it. Then there it is, staring you in the face; a pressure gauge that reads 2600 on a tank that is clearly a 3000. This is decision time. What should you do? Maybe ask the boat crew if there is another tank you could use instead, or just figure that you have been doing better on your air consumption? Another option could be to try to make the best of what you have, and try to check it ahead of time on the next outing. You’re standing along the rocky shoreline of your favorite local lake with a tank you just packed over 300 yards from the car, in the heat nonetheless, while wondering why it seems like you’re the only one that ended up with a tank that is not quite full. It seems to be so unavoidable, but there you are, trying to decide how to make the best of this situation.
Anyone who has dove for a while knows very well there are a lot of variables that can have an effect on your tank’s PSI reading. Some of which are controllable, and some that are not.
The most common issue we see locally is a valve that gets bumped during transportation, causing the tank to leak. When you have six air tanks, two bags of dive gear, a tent, sleeping bags, weights, food, and clothes tightly packed in the back of your vehicle, your car looks like you now live out of it and it’s all too often that something will shift on that handle of that precious cargo loosening it ever so slightly.
The second most common issue would be a temperature change with the tank that will generally drop your PSI 50-200 pounds. Filling a tank, which causes it to heat up, can cause this and then when it cools, the pressure will drop. This also happens when your tanks are being stored within 100 degree temperatures in the car, then soon after, you’ve submerged them in a cold 50 degree temperature lake. Even some inexperienced facilities will fill tanks much faster than what would be considered safe which also causes the tank to heat up unnecessarily. There in by cheating their customers out of there full fill.
Most tank valves see a lot of abuse and can develop a slow leak in the handle which isn’t always easy to detect as it may only leak in a certain position. It could also be so small that it cannot be heard, but only seen under the water. This is when we really appreciate our customers letting us know if there is something wrong with a piece of gear when it is returned to us so that it can be diagnosed and fixed before the next customer rents it, and before its’ inspection time is due.
A difference in gauges can also be expected to a slight degree. Be that the gauge of the dive facility doing the fill, or the gauge on your 25-year-old consoles spring versus your brand new dive computer. This variation can be high, but in our opinion, it should ideally not be more than 10-30psi.
Last but not the least, one cause that’s common especially on travel dives, is that the person filling the tank just stopped it a bit too short for some unknown reason.
Keep in mind that it could be one, or multiple things that give you a less than ideal or expected starting pressure, and until you do a bit of fact checking, it would be sheer speculation to say what the cause truly is. However, none of which are a catastrophe if you just take a minute to figure it out and fix the problem before you depart for your dive.
I try to make checking my tank pressure a habit well before my dive, on all my dive events whether they’re local, or halfway around the world. Also, I have never had any dive operator not willing to work with me to remedy the situation in one fashion or another as almost all want their customers to have great dives.
Some thoughtful customers of ours have brought it to our attention that our tank fills where not going out the door with the appropriate amount of air. Upon doing a bit of Q&A to find out how this is truly happening, the problem had been that our fill whip gauge was more inaccurate then we expected and in conjunction with a couple of leaking valves there are a few of our customers that ended up not getting the full amount of air that should have been in their tanks. We understand exactly how frustrating this can be to a diver, as we have all experienced this on one occasion or another, when they reach their dive site and are a bit short of the expected amount or air for the dive. This is also why we fill tanks the way we do to try our best to eliminate this problem, and make sure our customers are getting their money’s worth out of their tanks as well as filling tanks as safely as possible. If you would like to know the details for filling tanks, or why we do it the way we do, please feel free to stop by and ask.
We have now remedied the problem with a new calibrated gauge and would like to thank all of our customers for being so understanding by offering an entire weekend of free air fills. We have also taken one more step in providing our customers with some assurance that they are getting full tanks of air when they leave our facility by having an additional check gauge at the front of our store for any customer to use on tanks to see the PSI before they leave.
Thank you to our customers who help us to improve our business as we take great pride in doing our best to make sure our customers are well taken care of.
If not, come by and get your tank filled and get out for a dive! Bring any scuba cylinder with current inspections by the store starting October 5 to October 7th, and get your free air fill.