Choosing Your Mask
The first step for any diver is to choose a dive mask. There are all sorts of diving masks – varying types, designs, colors, sizes, straps, and even interior air volumes. The type of dive mask you choose depends on what kind of diving you will actually be doing. If you are scuba diving, you have more variety. However, if you are freediving, you will generally want a freediving specific diving mask.
Generally speaking, masks for freediving tend to be low-volume masks. The interior air volume (the volume of air space between your face and the glass) should be smaller when you freedive. You can certainly wear a scuba diving mask (or a higher volume mask) when you freedive, but as you descend, the air inside the mask gets compressed creating suction. The greater the air volume, the greater the suction effect. Suction isn’t a massive issue except that the primary way of relieving the suction pressure is to exhale a bit of air from the nose into the mask. The higher the volume, the more air has to be exhaled to equalize the mask pressure.
When you’re freediving, every milliliter of air is precious because it has a direct correlation to the amount of air available in your lungs to provide the oxygen you need to extend your bottom time. The more air you exhale to fill a mask is less time you can spend on the bottom. So, it makes logical sense that a lower volume dive mask would be preferable to one with more volume. In scuba, the diver is constantly breathing in and out and exhaling a bit of air into the mask doesn’t shorten the diver’s bottom time. In that regard, a scuba diver can choose any volume mask they desire, but a freediver should tend toward a low volume mask.
Fitting Your Diving Mask
The way you fit a mask, or determine whether or not it actually fits, is to move the strap out of the way (generally by flipping it forward in front of the glass) and then placing the mask gently on your face. Breathe in just a bit to get the mask to suck against your face. You don’t need to do this forcefully, just a little bit to get it to seal all the way around. If the mask won’t seal, the mask doesn’t fit. However, if the mask seals and stays on your face without having to keep sucking in air, then it fits. Make sure there isn’t any hair between the mask skirt (the rubbery edge that creates the seal around your face) – hair will keep the mask from sealing properly, and it will definitely leak.
Once you determine that the mask fits, you can adjust the strap to gently hold the mask on your head. You do NOT want the strap so tight that it is squishing the mask against your face or causing you discomfort. Tighter is NOT better. If you have to have a super tight mask strap to keep your mask from leaking, it doesn’t fit properly. The mask strap just holds it in place, it doesn’t make it seal.
Clean Your Dive Mask
Once you’re sure the mask fits and that you are going to keep it, you need to clean the mask. Many manufacturers put a chemical on the glass to prevent scratching during the manufacturing and shipping process. This coating needs to be removed or the mask will fog up during the dive. You can use a coating removal solution or use just some toothpaste (the cheap paste kind, not the gel kind). The minimal grit in the toothpaste will help buff out the coating. Once you’ve finished buffing the mask, make sure to rinse thoroughly. Minty fresh eyes are not comfortable!
A note about the glass – the glass in the mask should either be tempered or an acrylic so that it doesn’t break into sharp pieces if it is dropped or damaged. If your mask has a crack in it, it’s time for a new mask. When in doubt, throw it out!
More Scuba Freediving and Snorkeling Masks