Tank valve bubble

[KneeDeep]

All,
During a buddy check with my wife, I noticed a small hole on the valve with micro bubbles. I seen all our valves have this hole, but what is it purpose?

We did have another tank, so played it safe and wont dive it till I have it looked at.

[Desert Diver]

Probably the overpressure blow-off disc. When they change them they sometimes leak.

[CaptnJack]

Have a picture of the hole?

If its the hole on the side of a DIN tank opening?
That is there on purpose so if you were to unscrew the DIN fitting under pressure (not a full tank but under less pressure its possible to do this) that the space behind the reg can vent before all the threads are undone and it blows off into your hand.

The hole on the back or side of the valve opposite the knob (depends on brand)?
That is the burst disk. As they age and corrode they leak a little. They should be replaced at least every 5 years at hydro time.

[KneeDeep]

The hole on the back or side of the valve opposite the knob (depends on brand)?
That is the burst disk. As they age and corrode they leak a little. They should be replaced at least every 5 years at hydro time.

It is on the side of the valve. Looks like it's time to have the burst disk replaced... Thanks Jack.

[CaptnJack]

You can do it yourself, can get burst disk units from Piranha and then you only need a torque wrench. Proper burst disk torque is about 8-9 foot lbs (ALOT) less than you'd think. Do not over tighten or you will sheer the head off the plug.

[doublesunder]

Try replacing your regulator face o-ring, a bad o-ring at that point can allow it to leak from this tiny hole.