John Edmonds recently recalled a story about a brand new, but inaccurate high pressure gauge (tank gauge). The gauge displayed 300 psi more than the pressure that was actually in the tank. This condition is not very significant at full tank pressure, when the gauge would read 3300 psi on a tank that actually contains 3000 psi (a 10% error).

Unfortunately, things are much different as the tank nears the lower end of the pressure range (where accurate pressure information is most critical). When the gauge displays 500 psi the tank would have only 200 psi, and the tank would be empty when the gauge displayed 300 psi…not a good scene.

If you suspect one of your tank pressure-sensing components is inaccurate, the best way to check it is to work with your dive buddy. If you each check a tank’s pressure and your equipment agrees, both units are probably accurate. If, on the other hand, the two units don’t agree, it’s time to find a third pressure gauge, which will almost certainly agree with one of the first two and confirm a problem with the suspect device.

If you suspect there is a problem with any piece of your dive gear, discuss the issue with a dive buddy or dive shop technician. Reach a resolution before you next go diving with that gear.

Dive Safe!
Dave Wills