Regulator Free flow

What the weekend's cold water diving highlighted was the possibility of regulators going into free flow (where the second stage sticks open releasing a continuous stream of air), particularly during deep dives when the temperature of the water is at its coldest.

Thanks to Vinni at Aquasport International in Birmingham, below are a few easy steps to preventing free-flows and dealing with them should they happen.

• Ensure your regulator is well maintained and serviced properly.
• If you are using hose protectors, pull them down a little to expose the metal fittings at the first stage. These will act as a heat sink warming the air in the hose slightly before it reaches the second stage.
• Keep your regulators in the passenger compartment of your car - not in the unheated boot - on the way to the dive site.
• Ensure the inside of the regulator is kept dry, particularly between dives.
• Don’t leave the air turned on for long periods of time between dives. Once you have checked the system after assembly, purge and switch off.
• Avoid breathing into you second stage prior to buddy checks and avoid purging your regs.
• Don’t leave equipment on the ground where it could be colder and damper than a few feet higher.

During the dive:

• Set your ‘dial-a-breath’ resistance knob to it's least sensitive point where it requires most effort to crack it, and the venturi switch across the air flow.
• Enter the water with you primary second stage in your mouth and the octopus mouthpiece down.
• Try to avoid high impact entries, such as giant strides which put gear under strain.
• Also avoid long surface swims which could leave you over-exerted and with a higher than normal breathing rate.
• Keep your regulator in your mouth for the duration of the dive.
• Try not to use the purge button at any point. If you have to use gently progressive pressure rather than one sharp stab
• Avoid deep or strenuous dives which will push regulators to their limits.
• Maintain proper buddy contact to ensure you are there for each other in the event of a problem.

If the worst does happen, stay calm and remember your training. We all trained to breath from a free flowing reg in our open water training and it is straight forward to ascend while doing so. You may find it stops at shallower depths.

You can also ascend on your buddy’s alternate. While doing so and if it is safe, get them to turn off your cylinder for a few moments and open the valve again slowly to see if the free-flow has subsided.

Thankfully, I've only ever had to bring one diver up from depth (20m) after a free-flow and the training kicked in perfectly. It's not as daunting as you might think.