Short answer: Researchers haven't settled whether full-face snorkel masks are more dangerous than a traditional mask and snorkel. One lab study found they led to more carbon dioxide build-up and lower oxygen levels during light exercise. A study of snorkel deaths in Hawai'i pointed to a different cause and found no evidence that carbon dioxide rebreathing was involved. What is clear: full-face masks can't be used for diving below the surface, and they're harder to remove quickly. For most people, a traditional mask with a separate snorkel is the simpler, well-proven choice.
Disclosure: Scuba Prime sells traditional masks and snorkels, not full-face masks. We've tried to summarize the research fairly and list the original studies at the end so you can read them yourself.
What is a full-face snorkel mask?
A full-face snorkel mask covers your eyes, nose and mouth in one piece, with the snorkel built into the top. You breathe normally through your mouth or nose instead of biting a mouthpiece, which is why many first-time snorkelers like them.
A traditional setup is a dive mask that covers only your eyes and nose, plus a separate snorkel with a mouthpiece.
What the research says
Carbon dioxide build-up (lab study, 2023). Researchers in New Zealand had 20 people breathe through two full-face masks and a conventional snorkel, at rest and during light exercise, in a dry lab. During light exercise, 45% of full-face mask runs had to be stopped because carbon dioxide rose past a safety limit, compared with 20% of conventional snorkel runs. The authors concluded that full-face masks "may result in rebreathing" because air doesn't flow in only one direction. That can raise carbon dioxide and lower oxygen.
Snorkel deaths in Hawai'i (2022). Researchers reviewed 32 snorkel-related drownings in Hawai'i from 2017 to 2019. They said carbon dioxide rebreathing has often been suggested, but "no science to support it as a serious contender has appeared." Instead, they proposed that some deaths come from fluid suddenly building up in the lungs (pulmonary edema), which may be linked to breathing against resistance while lying in the water. Most victims were over 50, and two of the deaths involved full-face masks. The authors said the role of full-face masks needs more study.
So the two studies point in different directions on carbon dioxide. Neither proves that full-face masks caused the deaths.
Practical differences that don't depend on the research
- You can't dive with one. A full-face mask covers your nose, so you can't pinch it to equalize your ears. That means you can't swim down more than a short distance, and you can't use one for scuba.
- It's harder to take off fast. If you feel short of breath, pulling a full-face mask off takes longer than spitting out a mouthpiece and lifting a mask onto your forehead.
- Fit matters more. A full-face mask has to seal around your whole face, including your chin. A poor seal can let water in around your mouth.
Snorkeling safety tips, whatever you wear
- Snorkel with a buddy.
- If breathing feels hard, stop, lift your head out of the water and breathe normally. Don't push through it.
- Take it easy on your first day in the water, especially after a long flight.
- If you're over 50 or have a heart or lung condition, talk with your doctor before snorkeling.
- Wear a snorkel vest or flotation if you're not a confident swimmer.
A traditional alternative
If you like the wide view of a full-face mask, a panoramic mask gives you a similar open feel with a separate snorkel. Our Scuba Prime Pano 3 is a three-window mask with tempered glass lenses, built for a 180° panoramic view. Your mouth stays free, so you can use it with a snorkel or a scuba regulator. The Pano 3 Snorkel Set adds a dry-top snorkel that seals when you go under.
It's designed for teens (13+) and adults and isn't recommended for small faces. You can return it within 30 days if the fit isn't right.
FAQ
Are full-face snorkel masks banned?
We're not aware of any US ban. Tour operators set their own rules, so check with yours before your trip.
Can kids use full-face snorkel masks?
Ask your child's doctor and your tour operator. The research above was done on adults.
Is a traditional snorkel harder to use?
Biting a mouthpiece takes a few minutes to get used to. A dry snorkel makes it easier because waves won't splash into the tube.
Sources
- Grundemann LJ, Vrijdag XCE, Wong RW, Gant N, Mitchell SJ, van Waart H. "Full-face snorkel masks increase the incidence of hypoxaemia and hypercapnia during simulated snorkelling compared to conventional snorkels." Diving and Hyperbaric Medicine, 2023;53(4):313–320.
- Foti PR, Wilcox CM, Goto RS. "Factors Contributing to Snorkel Drowning in Hawai'i." Hawai'i Journal of Health & Social Welfare, 2022;81(3):71–76.