LobsTerminator
Registered
A dive shop in Florida has a habit of letting the remaining (up to about 50-100 psi) air out of my tank whenever I request a Nitrox fill. They like to start with a fresh tank. My concern is this- They put the tank outside to do this.
While letting the air out of the tank, the tank gets cold, the surrounding temperature is hot and humid. Condensation builds up both on the tank and valve.
In addition to the condensation buildup on the tank and valve there is another more pressing concern-
The partial pressure of the moist air outside is higher than the partial pressure of the moist air in my tank- assuming there is no moist air in my tank to begin with.
I believe the difference in partial pressure would allow for moist air to migrate into my tank even though the tank is venting and has a positive pressure.
I have experienced this situation while working in an environmental test lab using thermal chambers to test aerospace components. The chamber was pressurized with nitrogen gas, but it would still snow inside the chamber at cold temperature due to leaks and moisture intrusion from the surrounding air in the test lab. The fact that the chamber was pressurized did not keep the moisture out.
Any comments or experience with this would be appreciated.
While letting the air out of the tank, the tank gets cold, the surrounding temperature is hot and humid. Condensation builds up both on the tank and valve.
In addition to the condensation buildup on the tank and valve there is another more pressing concern-
The partial pressure of the moist air outside is higher than the partial pressure of the moist air in my tank- assuming there is no moist air in my tank to begin with.
I believe the difference in partial pressure would allow for moist air to migrate into my tank even though the tank is venting and has a positive pressure.
I have experienced this situation while working in an environmental test lab using thermal chambers to test aerospace components. The chamber was pressurized with nitrogen gas, but it would still snow inside the chamber at cold temperature due to leaks and moisture intrusion from the surrounding air in the test lab. The fact that the chamber was pressurized did not keep the moisture out.
Any comments or experience with this would be appreciated.