Coroner warns against full-face snorkel masks after fatality - Hurghada, Egypt

[Divedoggie]

The mask holds the snorkel perfectly in place. Rarely does it accidentally dip below the surface. If water does enter the mask, it trickles below the pocket and out through the purge valve.

The snorkeler is able to breath through both the nose and mouth. This enables the snorkeler to talk. Works especially great with kids because they want to talk and point things out all the time.
Most kid's snorkels are tiny, so it dips below the surface easily. Most kids mouthpieces are poorly made and ill fitting. The FFM eliminates that problem.

The best designs for Full Face Snorkel Masks decrease the amount of extended airway. Hypercapnia is a consideration with all snorkels and scuba gear because CO2 can linger in an extended airway and continuously be rebreathed. It is also a consideration for people who use improper breathing techniques.

CO2 elimination in the properly deigned masks is accomplished with exhaust vents near the temples of the mask and a good purge valve at the chin. Most importantly, the mask must have a good one-way valve at the base of the snorkel piece. This allows clean air to enter through the snorkel, and prevents exhaled air (largely CO2) to reenter the snorkel.

 

[John the Pom]

Not all Full Face Snorkels are created alike! There are those which pass ANSI Standards for CO2 elimination. Hands down the best piece of equipment that I had my children use when they learned to snorkel.

Neither of my kids were especially confident in the water when they were young, but both of them took to regular masks and snorkels without any issues at all (and went on to SCUBA diving later). I've never been happy with the idea of these FF snorkelling masks. If you can't manage a regular mask and snorkel, I wonder if you are really safe in one of these.

 

[Tritip]

Never used one before is there more fog? Previous moisture from only eyes and some nose is now fully breathe lungs moisture.

 

[Divedoggie]

Never used one before is there more fog? Previous moisture from only eyes and some nose is now fully breathe lungs moisture.

I'm definitely not trying to sell everyone on a FF Snorkel Mask. Just like a FF Scuba Mask, they aren't for everybody. Just wanted to point out that just because some coroner warns against FF Snorkel Masks, they aren't all bad.

I personally use an old fashioned snorkel for snorkeling and skin diving. A good FF Snorkel Mask is a good intro mask for kids, or new to the water adults for the reasons outlined previously.

The breathing pocket on the inside is separate from the window. So there is no fogging issue. The air that you breathe has no more moisture in it, than through a regular snorkel.
The bigger drawback is they are made for surface swimming. If you can equalize your ears without a valsalva maneuver, then they are ok for a shallow breath hold dive.

 

[John C. Ratliff]

Do you know what the design differences are that make some Full Face Snorkels better for CO2 elimination ?

The change would be in the fitting of the interior oral/nasal mask, and the separation of inhalation and exhalation routes. The oral/nasal mask needs to seal on the face to be effective. Some do, apparently most do not.

One other aspect is the advertising that the full-face snorkel mask user can breathe “normally.” This misperception of snorkeling would allow a person to breathe shallowly, which doesn’t really bring in a lot of “clean air” (air lacking the CO2 buildup). Breathing should be deeper than normal, as it is with a regular face mask and snorkel combination. This is not hyperventilation, but using the full inspiratory volume on each breath.

SeaRat

 

[John the Pom]

[...]

One other aspect is the advertising that the full-face snorkel mask user can breathe “normally.” This misperception of snorkeling would allow a person to breathe shallowly, which doesn’t really bring in a lot of “clean air” (air lacking the CO2 buildup). Breathing should be deeper than normal, as it is with a regular face mask and snorkel combination. This is not hyperventilation, but using the full inspiratory volume on each breath.

SeaRat

This is an excellent point. Learning with a traditional mask & snorkel teaches you a lot, like what it feels like to get a mouthful of water, or your mask flooded, and deal with it calmly. I had a friend who was very nervous, and dropped out of his first attempt at an O/W course. He had never learned to snorkel. So, we spent a few weeks getting used to snorkelling in the open water and, after that, he breezed through O/W and went on to become a very keen SCUBA diver.

As you say, breathing with a mask and snorkel isn't "normal" - it takes a bit of practise to learn how to do it comfortably. But once you have learned that, you have gained a lot of skills and confidence. A device that makes it too easy may give you the confidence, but it may not give you the skills and experience to deal with things going wrong.

 

[wgw04024]

Seeing lots of these in Grand Cayman this week.

 

[BlueTrin]

Seeing lots of these in Grand Cayman this week.

They were getting more and more popular even before covid. They are really easy to use for someone who hasn’t used a snorkel or who does not go in the water often.

 

[Seaweed Doc]

I'm having trouble seeing the connection between the FFM and IPE. I'm stretching here, but maybe the added dead air space requires greater suction. That could pull fluid in, maybe?

Another possibility is the FFM effectively drowned the victim. IPE can present with spewing out foam. In large volume. That foam wouldn't drain out of the bottom of the mask, at least not quickly, and could be re-aspirated. This would require an incomplete news report, and I suppose they happen.

I'm speculating wildly here. I'm really skeptical about the connection, and grabbing at any possibility that might explain it.

I get the high blood pressure/hormone replacement connection. I think hormone replacement therapy can cause cardiac issues which, along with high BP, might push fluid into the lungs or fail to clear it.

Edit to add: I've seen too many FFM failures (usually involving flooding) to think of using them. I'd never put my kids in a FFM. I understand there are better and worse models. But I don't see the need: I made sure my kids could swim before they could go snorkeling. The biggest advantage of FFM I can see is being able to nose breathe. I wouldn't take kids in water they couldn't stand up in until they could properly swim, which requires knowing not to nose breathe. But I could see others doing it safely if they kept eagle eyes on the kids while snorkeling. And ideally having a second parent watching the first in case they're incapacitated. (I've seen scary situations where surf could easily have driven dad onto a rock, leaving behind a very young non-swimming child in a FFM floating alone.)

 

[John C. Ratliff]

I am not a doctor, and so will stay away from speculating on IPE and the use of a full-face mask.

Saying that, a full-face mask presents several restrictions to breathing. First, there is the needed obstruction that keeps water out of the snorkel, which also adds some restriction to the inhalation. Second, the length of the tube adds some resistance (all tubes, including snorkels). Third, in order for the inner mask to work, it needs a set of non-return valves, so as to not allow rebreathing of mask air. Fourth, there is also restriction on the exhalation side, from the routing of the air out to the non-return valves involved.

Now, about nose breathing. That would contribute to very much smaller inhalations, which you really don't want to encourage in a full-face mask.

SeaRat