Question Breathing the hose dry (during valve drills) - Risks with water entry into first stage?

[halocline]

Hello,

People always say that you shouldn't submerge an unpressurized regulator (first and/or second stage) for soaking after dives, and that it should be attached to a cylinder and be pressurized..

But still, the majority of technical divers regularly do valve drills, including myself. That means breathing the hose dry before switching to backup and so on. During this sucking the hose dry-moment, the first stage of course becomes unpressurized, and most often the first stage becomes a little loose on the valve (meaning it shouldn't be able to safely form av protecting seal at depth during that moment?)

Could somebody explain to me the risks and effects to the first stage during above?

Thank you

Some people sometimes say not to submerge an unpressurized regulator, but the majority of divers simply use the dust cap to keep water out of the 1st stage, and it works. I have soaked regulators unpressurized for hours on end with no problem whatsoever. Screw-on din dust caps seal exactly the same way as the tank valve. Yet the myth lives on.

Valve drills present no problem to 1st stages because the 2nd stage valve is closed after it's out of your mouth, keeping water from migrating up the hose into the 1st stage. And there's usually some pressure left in the hose; as soon as the hose pressure gets lower than IP, the reg becomes a lot stiffer to breathe on and you move on to the other post.

Now if you completely depressurized a regulator, then held the purge button open while elevating the 2nd stage to allow any residual air to escape and be replaced by water, that would be bad.

 

[ThatDogDontHunt]

Some people sometimes say not to submerge an unpressurized regulator, but the majority of divers simply use the dust cap to keep water out of the 1st stage, and it works. I have soaked regulators unpressurized for hours on end with no problem whatsoever. Screw-on din dust caps seal exactly the same way as the tank valve. Yet the myth lives on.

It may make sense to know what your reg manufacturer recommends?

Mine has the following gems:

"After the dive, blow all water out of the dust cap with clean dry air and place the cap securely
on the regulator inlet.

With the dust cap securely in place, rinse the first and second stages in clean fresh water.
DO NOT depress the purge button before or during rinsing since this may introduce water into
the second stage and the low pressure hose. Shake or blow all excess water from the second
stage and allow the entire regulator to air-dry before storing."

It does not define "how" to rinse (soak vs shower), but does appear to be more worried about water entering from the second stage as opposed to the first. And yes it instructs you to use your tank to blow water off the dust cap!