Why Does Your Regulator Let You Down After Servicing?

We've all been there, as the writer of this month's travel story explains. You travel across the world to some exotic dive destination and during your first dive, your regulator leaks air. And you just had it serviced! So why does it happen?

Truthfully, it's an indictment of your regulator service technician. You see, they often tune the regulator so it's as effortless to breathe from as possible, but they cannot allow for the plethora of tiny O-rings in a modern first stage bedding in. Your regulator might be spot-on when it leaves the service workshop, but once it's been shaken around in the lower pressure of an airplane, it might need readjusting.

The function of the first stage is to reduce the pressure of gas coming from the tank to 8 or 10 bars more than ambient pressure. The second stage then reduces this pressure to match the surrounding water, thereby making breathing near effortless. If this interstage pressure is too high, the spring on the valve in the second stage is not strong enough to close it and your regulator appears to leak. My own rule is never to take a recently serviced regulator on a trip unless I had first tried it on a dive at home or had a spare first stage packed alongside it.

Testing your regulator on a dry tank at the dive shop or in your garage isn't enough to determine whether you will have a problem after a long flight. Only time will determine whether you have a problem then.

Setting aside the possibility that the interstage pressure has been set incorrectly, the specter of a service technician botching a service because he doesn't have the exact correct service kit for the regulator in question haunts all of us - but it happens. Sometimes these people forget that it's life-preserving equipment for use in a hostile environment.

- John Bantin