Choosing the right mask
To appreciate the underwater world, we at the very least must be able to observe it clearly. Being designed for an air environment our eyes are unable to focus when opened beneath the water’s surface, and the creation of an air space by utilizing a diving mask or goggles, is necessary for our eyes to function properly.
Let’s start with the distinction between a diving or snorkeling mask (which are almost identical) and goggles, both allow us to see clearly underwater however the former encloses the nose, whilst the latter does not. Goggles are really designed with swimmers in mind, however the lack of a nose pocket makes it unsuitable for snorkeling or diving as it doesn’t provide airway control whilst using either a snorkel or scuba regulator, and it also doesn’t allow for the equalization of the air spaces surrounding the eyes. This may result in the inhalation of water into the lungs or a barotrauma to the eyes. That sounds really scary so we’ll stick to a proper mask, one that’s suitable for our activities. A diving mask makes a good snorkeling mask but the opposite isn’t necessarily the same, the difference would be found in the lens material. Some cheaper snorkeling masks utilize polycarbonate or glass lens neither of which are suitable for scuba as the polycarbonate is not only susceptible to scratches, but is usually not strong enough to resist the increased water pressure experienced on scuba, while glass has the propensity to splinter into shards when broken. Diving masks are fitted with tempered lens which is much more resistant to breakage and would shatter (like a car’s windshield), rather than splinter.
Over the long term, investing in a quality diving mask whether you plan on snorkeling or diving is probably a good idea, it will last you many years and you just may try scuba at some time in the future! Diving masks come in all shapes, colors and sizes so here are some things to consider when purchasing your new mask other than pricing: Single lens, double lens or tri-view lens? A single lens allows for unobstructed forward vision while some double lens masks, can be easily fitted with ‘off the shelf’ prescription lens. Tri-view masks provide good peripheral vision, but at the expense of a greater bulk and internal volume.
PVC or silicone? The skirting of the mask (part that is in contact with your face) creates the seal to prevent water from entering. Silicone is more expensive, but is suppler than PVC which results in a better seal and more comfortable fit. It also lasts longer than PVC. Silicone wins!
Prescription lens? Objects viewed underwater through a mask appear approximately 25% larger and closer due to the refraction of light, as a result you can use a normal mask if your prescription is about -1 diopters. However if your eyesight is weaker, you’ll benefit from using a prescription mask. It’s not as expensive as you may think and many manufacturers carry a line of optical masks with lens ranging to -7 diopters in half increments. Of course this isn’t necessary if you wear contacts. Eyesight okay, but need a bit of help reading the smaller numbers on your gauges? Small magnifying lens can be attached to the bottom of the mask lens, creating instant bifocals.
Low, medium or high volume? A low volume mask allows for easier clearing of water and places the lens closer to the eyes, thereby increasing your field of vision. It is also less prone to flooding when diving in strong ocean currents. For those with high brows, the low volume mask can press uncomfortably, so a larger volume mask would be desirable.
Nose pocket? You’ve got to have one, didn’t you read paragraph two? Ensure that you can reach your nostrils comfortably to equalize your ears. Make sure that your nose fits properly, too small a pocket will result in a hickey on the tip of your nose attracting more attention at the dinner table than Rudolf. I kid you not!
Purge valve? A purge valve is a simple one way flapper valve located to the base of the nose pocket which facilitates the clearing of water from the mask. Simply look downwards and exhale through your nose. Voila! The downside is that it can prevent you from pinching your nostrils shut with one hand during equalization of the ears and it leaks water if sand gets stuck in it, bummer.
Color? Guys typically like blue or black, the gals tend towards brighter colors. You’re spending money, you may as well get a color that you like. Frameless? Traditional mask design (95% of masks) utilizes a frame which provides the greatest choice of shapes and colors, a frameless mask is lighter but only comes in black or clear.
All of this aside, the mask is useless unless it fits well and is comfortable, so how do we check this?
Test 1: Start by folding the strap forward, place the mask onto your face and inhale gently through your nose. A vacuum will form, and the mask will ‘stick’ to your face if a proper seal has been made. If it fails to do so, be sure to check that you haven’t any hair trapped between your forehead and the skirt and try again. If you can’t get a seal, choose another mask. For those you with a thick mustache, you’ll not get a seal on any mask without application of Vaseline jelly.
Test 2: Holding the mask onto your face (but not inhaling), look into a mirror and observe where the skirt contacts your face at the corners of your eyes. The inner seal of the skirt should be in contact with your face and should not be too close to the corners of your eyes. If the inner seal isn’t in contact, choose another mask.
Test 3: Holding the mask on your face, draw the strap into place. Adjust the strap so that the mask is snug, not too loose nor too tight. Be mindful of your strap positioning, too high draws the nose pocket uncomfortably against your nostrils, too low allows the mask to sag over your upper lip, both positions will cause the mask to leak whilst in use. If you’ve long, straight hair then mask straps tend to slide downwards, form a ‘pony tail’ or ‘bun’ and place it in the center of the mask strap. Is it comfortable? Is the field of view to your liking?
Okay, you’ve paid the man and eager to put your mask to use. Not so fast….hold up…. you’ll have to prep your mask before its first usage. In order to reduce fogging, the lens on a new mask should be thoroughly scrubbed with toothpaste or a light cleaner cream such as Cif, in order to remove traces of silicone that invariably get on it during manufacturing. Bear in mind that you’ll still need to apply ’no fog’ solution, saliva, liquid soap or baby shampoo to the lens of your mask prior to usage in order to reduce fogging.
Lastly, you’ll want to protect your investment so, rinse in fresh water, dry and store your mask in a ‘mask box’ in order to prevent deformation when not in use. Avoid exposure to high temperatures such as the dashboard of a car and examine the skirt and strap for small tears prior to use.
Whew! That’s a lot to take in. Who knew that there’d be so much to say about something as basic as a mask? Be sure to visit your local dive center when choosing a mask as the sales person will not only be able to assist with the various features, but more importantly assist with selecting a mask that both fits, and is comfortable. Those being the most important criteria!