Equipment Focus – The Snorkel
The humble snorkel is often a discarded piece of kit by divers and considered a very simple bit of equipment. In it’s basic ‘J’ shape that certainly isn’t difficult to believe but there is actually quite a lot involved with designing and developing a snorkel, especially as consumer demands and expectations develop over time.
Manufacturers have to think about essential considerations like air flow rates, turbulence, snorkel length, shape and material before they even get into the complexities of adding creature comforts like purges, dry valves, clips, wave deflectors, etc that are on the latest modern snorkels. To go to the extreme, the snorkel that is integrated into the Ocean Reef Aria features a one way flow system that circulates fresh air around the entire mask to prevent carbon dioxide building up in the mask which is what separates the Aria from its cheap copies (i.e. they don’t have it!).
When looking at buying a snorkel it is easy to believe that the most expensive snorkel or the one with the most features is clearly the best option. Some thought should actually go into your decision process. Are you using it primarily for snorkelling or diving? Are you confident in the water? Have you previously found snorkel mouthpiece uncomfortably big? There are so many things to consider!
The basic snorkel is a ‘J’ shape with a straight circular rigid tube normally leading into a softer lower section which angles the integrated mouthpiece towards the mouth. That is it, two components. Simple!
Whilst it does the job the design can easily be improved to reduce drag, improve stability, reduce the weight, provide a more comfortable fit.
The traditional circular profile of a snorkel is fine but tends to stick out from the side of your head quite considerably which affects your streamlining in the water and will often cause resistance and flapping when swimming quickly or against currents. The answer to reducing the drag profile without compromising on snorkel bore and flow rates is to give it an oval cross section that cuts through the water better as you are swimming.
Similarly, the straight upright tube of the traditional snorkel means that it often sticks out into the water rather than following the profile of your head. Add in a gentle curve here and there and the snorkel tube will hug the side of your head for further improved streamlining .
The last basic shape issue is the fixed angle of the lower section that delivers the mouthpiece to your mouth. The design is obviously based on the average person, whoever that is, and won’t always offer the best fit or comfort and may pull on one side or sit at an awkward angle. The fix is replacing the fixed angle with a flexible corrugated silicone tube that allows the mouthpiece to be angled and positioned more naturally for you. It is rare to see these days but cheaper snorkels used to have the corrugation on the inside of the tube but this causes significant turbulence within the snorkel which will lower the breathing efficiency so make sure the one you buy has the corrugation on the outside .
One final consideration that isn’t an issue for well designed, mainstream snorkel brands is the actual overall length of the snorkel. When you breathe you never completely exhale all of the air from your lungs and airways. This is often referred to as Dead Air which doesn’t get exchanged with fresh air. Our lung capacity and the fact we only use about 25% of the oxygen we breathe in (air contains approx 21% oxygen and we breathe out approx 16%) means this isn’t a problem in everyday life but as soon as you start extending your airways the dead air space gets bigger and you have to think about carbon dioxide build up. Unnecessarily long snorkels not only have a great dead air space but are also heard to clear water from as you’ll require more air to push the water all the way out of the snorkel.
The traditional basic snorkel is normally made from two materials, a hard plastic that forms the snorkel tube and a flexible rubber or silicone that is used in the lower section and mouthpiece.
Things have obviously moved on with technological and material advancements that give manufacturers a lot more choice. For instance, the snorkel tube made not be made from a completely rigid plastic but a more flexible material that is strong enough to provide structural stability but soft enough bend and conform should it, for instance, be stepped on without causing it to permanently deform or break.
You’ll also find various levels of flexible in the silicone elbows that allow the mouthpiece to be positioned comfortably in the mouth. Some snorkels features, a really flexible silicone that allows the mouthpiece to drop away fully when not in use but there are also snorkels with a less flexible silicone compound that will keep the mouthpiece closer for easier and quicker relocation whilst snorkelling.
Valves fitted to snorkels are nothing new but they have got considerably more reliable and efficient over the years. Valves are an excellent feature if you aren’t that confident in the water and worry that water will get into the snorkel and disrupt your breathing.
Many snorkels are fitted with a purging chamber and one-way valve that is fitted beneath the mouthpiece and helps to collect water and clear the airway by allowing it to either drain out through the valve naturally using gravity or be forced out by a sharp exhale.
The top of the snorkel tube can also be fitted with either a valve or a series of water deflecting vanes. The deflecting vanes, also referred to as a splash or wave deflector, work to divert and channel water away from the snorkel opening but are only designed to combat splashing water and will not prevent water entering if you submerge the snorkel.
Top of the range snorkels are often fitted with a dry top valve that will often feature water deflecting vanes for additional surface protection but also incorporates a float valve that closes a flap over the end of the snorkel when it is submerged to prevent water from entering. These are great for the less confident snorkelers but if you regularly duck dive whilst snorkelling you may find the trapped air in the snorkel a bit of a hindrance, causing additional buoyancy on one side of your head.
Clips and Retainers
It seems that even entry level snorkels feature some sort of retaining clip arrangement but you may still see snorkel keeper loops on cheap snorkel sets which work by trapping your mask strap between the loops that are fitted over the snorkel tube. Simple and effective but not the most convenient or easy to adjust which snorkelling.
The next step up is a clip that lifts up and traps the mask strap underneath it. These types of clips are free to slide up and down the snorkel tube with a little force for vertical adjustment and optimal mouthpiece positioning. They are more convenient that the silicone / rubber loops and allow for easier separation of the mask and snorkel for cleaning / storage / packing.
Top of the range snorkels often have a quick release clip, one half of which permanently goes on to your mask strap and is secured to the other half on the snorkel. This type of clip offers the most amount of adjustment with vertical, horizontal and rotational movement.
When going on exotic holidays and spending a substantial amount of money to be there, being underwater may not be everything, especially if you have a non- diving partner/friend with you, doing the tourist bit and experiencing the country and culture may be part of the trip, where visiting the sights and exploring beaches and coves with a snorkel can enhance that experience and giving a non-diving person an experience to see the underwater environment including snorkelling from a beach resort or on a dive trip during surface intervals.
Within the SISAC club we can train non divers to a BSAC Snorkel Diver qualification so that they are confident and competent in the water and understand the issues for a safe in water experience, and being a diver does not mean a competent snorkeller. More information here