We received a call from a male customer to who had purchased a mask online a few months prior to his tropical holiday. He used his new mask at a pool to verify the fit and was pleased with his purchase. His phone call came about a week before his holiday trip in which he stated that his mask now leaked badly. After going through some troubleshooting and not being able to determine the cause, we asked him to drop by our store in Rye, Victoria. As soon as he walked in, we immediately determined the reason. He had been cultivating a rather bushy moustache since he last used his mask.
The snorkelling/diving mask covers portions of the face which is inclusive of the area located between the nostrils of the nose and the upper lip, as well as portions of the cheekbone area on both sides of the face. The sealing surface of the mask skirt has to conform to those areas in a way that keeps it air tight. If it can not conform to these areas then it can not create an airtight seal, thereby allowing water to enter into the viewing area.
Having facial hair may have an adverse effect on the sealing capability of a mask in that the hair is breaking the seal that the skirt is trying to offer. Between a moustache and a beard, it is the mustache that would have the greater affect with regard to being the culprit for leakage as most beards are not often grown high enough up the cheek bone areas to interfere with the skirt.
Most snorkelers with a leaky mask will think that tightening the mask strap will alleviate this problem but in reality this may make the leakage problem worse. The material used in the skirt and sealing surface in the high quality masks we sell is a soft and pliable silicone. If you pull the mask strap too tight, the mask skirt will end up being stretched so it will not conform to the face. In this instance the simple act of smiling, or even removal of the snorkel, will cause the mask to leak. You should try loosening the strap to create a better seal. It may take a few tries to find the correct tension needed for the correct seal.
The way the strap in positioned on the back of the head may play a role in achieving the perfect seal. Moving it to the crown of the head will create a tighter seal around the lower portion of the skirt without compromising the flexibility of the silicone mask skirt.
These are just a few tips for you to try with the last two being the ones with the best success rates. With regard to the gentleman who came in the store... he ended up shaving his off, but before you hate us, just a reminder that after his adventure in the water he grew his moustache back.