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.

Scuba Diving Equipment Advice #1

After attending a scuba equipment seminar last night I thought I would pass on my advice for new divers when it comes to buying their own gear.

My first bit of advice is get kitted up as quickly as your wallet will allow - those with their own gear dive more. FACT. If you are learning it means you want to dive - and as much as possible - so get started with some kit.

So in the first of an occasional series, here's what to look for when buying a mask.

Find one that fits - place the mask lightly against your face and inhale slightly through the nose. The mask should sit on you face. Have someone peer into the mask to check the inner edge of the frame/skirt sits nicely against the face running either side of the face to the cheekbones. If it sticks out over the eyes, it's too small so try another.

Simple. But that is the easy bit. The trials and tribulations are now which one you pick from the plethora on the shelves of you dive store.

Go low volume - these are masks that sit the lenses closer to your eyes. This offers greater field of vision and are easier the clear when flooded. 'No-frame' designs reduce weight and provides one of the largest fields-of-view


see Tusa website

Lenses - should be made of tempered glass. Single-lens masks provide a broad, uninterrupted view but twin-lens masks have become increasingly popular because they typically have a lower internal volume.
They also allow for corrective lenses to be added for those with sight problems.
The size of the lens will affect the field of vision. Some masks now (like the Oceanic Neo 2, Tusa Visulator or Scubapro Spectra) have oversized lenses to increase the field of vision. Others such as the Oceanic Ion 3 and 4, Tusa Splendive IV or Scubapro Crystalvu have side windows to offer greater panoramic view for greater peripheral views.
Look for lenses such as Atomic's Ultraclear. Some lenses come with a green tint to them (place the mask over a piece of white paper to see) which is the result of iron impurities in low quality float or window type glass. This can distort colours underwater.
Some Atomic masks also come with anti-reflective coating which reduces the amount of light (between four and 12 per cent) reflected back by the lens surface to give a clearer, crisper view.

Skirting - Go for liquid or crystal silicone. It's softer and more durable and won't go rigid in cold water. Feathered edges where the skirt gradually thins out as it approaches the edge of the mask offer superior fit because they make contact more flexible. A double skirt offers an inner skirt around the inside of the mask which sits on the face, providing an extra seal and more comfortable fit.


see Tusa website

When it comes to colour, yes black looks cool but it may reduce light coming into the mask and give the impression of a restricted view, whereas a clear skirt will allow more light in and not have that problem.

Straps and buckles - make sure they have adjustable/swivel buckles to get a proper and comfortable fit. A neoprene slapstrap is also a good idea as it makes donning and doffing mask easier, sits more comfortably on your head and those with long hair won't get it snagged in the strap. Oceanic masks are now coming ready fitted with their own Neoprene Comfort Strap included.

Purge valves - some masks (Oceanic Ion 2, Scubapro Crystalvu Purge) come with a one way valve at the base of the nose pocket to make clearing easier without having to break the seal of the mask. As mask clearing without the valve isn't much more difficult the debate is still open about its use.

Once you've selected your mask, you might want to think about the matching snorkel, de-fog solution to help it stay clear and a mask bag for protection.

Hope that helps, happy shopping!