2 recent deaths where snorkelers happened to be using full face masks

[scagrotto]

So you’ve never seen one nor have you done ANY research yourself about them but you sanctimoniously lecture to us about lack of evidence.

Not very good at reading comprehension, are you?

I've done enough research to know that a lot of people *think* there's a problem with CO2 buildup, but all I've seen is a lot of references to the idea with nothing to back it up. A small number of snorkelers have died while using them, and a small number of snorkelers have dies while using a regular mask and snorkel.

As for not seeing one in person, feel free to explain how that's relevant to anything I said. The basic design is simple and straightforward, and it's hardly necessary to examine one to know how they're intended to work. I have seen quite a few pictures of various models and in every single picture that's clear enough to tell, the area that fits around the mouth and nose has what looks like one way valves to allow the fresh air to enter, and the purge valve for the exhaled air to exit the mask.

I haven't seen anything but supposition, so since you're clearly familiar with this "known" issue but didn't specify what it is I asked. Since you said the problem is with knockoffs I thought that perhaps there was a specific issue or defect, and that there might be actual evidence for it. Based on your subsequent post it looks like perhaps you've confused some supposition and opinions with evidence, but since it's now clear that you've actually seen this "known issue" first hand perhaps you'd be so kind as to share that knowledge with those of us who have only heard some anecdotes.

the type of person using this is not likely to be practicing or using this on a lot of occasions.

When I first became aware of the Tribord mask their marketing seemed to be heavily targeted towards people who had issues with regular masks and snorkels. There are certainly some experienced snorkelers who have used them, but what I've seen gives me the impression that they're a very popular choice with people who are new. I think that the people who choose these may be somewhat analogous to people who go on a tropical vacation and chose snuba instead of a resort course dive based on a perception that it's simple and easy, with little requirement for training.

 

[Akimbo]

If you have a normal CO2 response, and most people active enough to snorkel will, the buildup will be very uncomfortable leading to aborting the snorkel and ripping off the mask.

Very plausible and exactly the response I would expect from someone with decent watermanship skills. However, CO2 buildup is also panic inducing, which is a major part of the discomfort you describe. Other additional aggravating factors "might" contribute:

• a poor swimmer might be fearful of removing the mask
• mask fogging can be disconcerting to the inexperienced, which would be consistent with poor ventilation/CO2 and plastic lenses
• water leakage into a poor fitting mask can make inexperienced snorkelers lose confidence in the mask after swimming in water too deep to stand.

Any combination of these factors (and many others) could contribute to a perfect storm. The point is not to speculate on these particular incidents but to recognize that accidents very often are a cascade of small problems.

 

[tridacna]

Very difficult to fog this mask. By design. The eye pocket is isolated from the mouth/nose ensuring no air circulation and thus no introduction of warm moist air. I’ve tried my best to fog the Seaview with no success.

My experience with teaching snorkelers how to use the mask is quite positive. Even the most i experienced snorkelers have no problem removing the mask.

I believe that users should receive a training session before jumping into the ocean. For example, snorkelers should be instructed why they cannot attempt a free dive with it on etc.

 

[Akimbo]

Very difficult to fog this mask.

No all. Some of the YouTube images also show fogging. I use one in the shop with a powered respirator to protect from fine dust. It does fog until I hook up the hose from the back-mounted filter and fan. Mine is comfortable on me, as FFMs go. Picked it up for $30.

the eye pocket is isolated from the mouth/nose ensuring no air circulation and thus no introduction of warm moist air.

Very dependent on the fit.

 

[tech_diver]

Some random thoughts from someone who has never used a full face mask snorkel but spent a couple of decades working for full line manufacturers that build and sell conventional snorkels... (no real answers here)


CO2 build-up is a consideration even if you are designing a simple J tube. I remember in my first scuba course (1978), the text book specifically talked about a good snorkel design vs a bad one. It's all about the volume and flow.

CO2 build-up is a consideration in the design of commercial diving helmets and band masks. A lot of modern designs use an oral/nasal insert to reduce the dead air space and ensure proper ventilation.

It's my understanding that the high quality snorkel masks use an oral / nasal to prevent CO2 build-up but I've read that some cheaper versions aren't well designed and do allow CO2 build-up. It would be easy to imagine a poor imitation that isn't properly ventilated. Does anybody remember the kids snorkel mask that had two snorkels topped with ping pong ball float seals going directly into the mask? Any cheap, poorly built gear can be a problem underwater.

A major manufacturer of snorkel gear will have product testing and liability concerns that a knock-off maker doesn't.

If there are a group of poorly designed snorkel masks in use causing issues, it may be hard to detect statistically. We don't know how many of what kind are out there being used how often. Like the current discussion, we've had two incidents but we don't know yet what that means. If we knew they were the only two units in service and both caused incidents, it would change the discussion dramatically but I don't think we're sure of how many of what quality are out there. We also have to pick through an array of other variables that could cause issues to rule them out.

.

 

[tridacna]

No all. Some of the YouTube images also show fogging. I use one in the shop with a powered respirator to protect from fine dust. It does fog until I hook up the hose from the back-mounted filter and fan. Mine is comfortable on me, as FFMs go. Picked it up for $30.

Are we talking about the same Full Face Mask withe built-in snorkel? How do you connect a powered respirator to this without altering the integrity of the snorkel?

 

[Akimbo]

Are we talking about the same Full Face Mask withe built-in snorkel? How do you connect a powered respirator to this without altering the integrity of the snorkel?

I sawed the bulbous part off the plastic snorkel and attached a corrugated hose with a hose clamp. I wasn't concerned with using it in the water.

I'm not implying that this was the case in these accidents, but never underestimate the effect of panic when people are between uncomfortable and afraid in the water. These are the same people who have no business in the deep end of the pool. This product has its place.

 

[Coldbloodeddivers]

Wow

 

[Scott from LongIsland]

I got one of those full face snorkel masks for my wife a couple years ago. One of the warnings right in the manual was to not do hard physical activity with them.

My wife was using it and she saw that I was a bit far away from her so did some hard sprint kicking to get to me and had problems breathing with it. She said it was like she couldn't get enough air to breath and it was suctioning hard to her face making it difficult to get off. She did eventual end up ripping the thing right off her face and I helped her get back to shore. She will still use it but will be far more cautious about using it in the future.

It annoys me that they are selling these things to kids....

this is yet another instance where i have read that these things are tough to get off

 

[kelemvor]

Very difficult to fog this mask. By design. The eye pocket is isolated from the mouth/nose ensuring no air circulation and thus no introduction of warm moist air. I’ve tried my best to fog the Seaview with no success.

My experience with teaching snorkelers how to use the mask is quite positive. Even the most i experienced snorkelers have no problem removing the mask.

I believe that users should receive a training session before jumping into the ocean. For example, snorkelers should be instructed why they cannot attempt a free dive with it on etc.

If there's no air circulating through the eye portion how does it fog any less than a standard scuba mask? I've never snorkeled with one, so that seems counter intuitive to me. It looks in the photo like there is a one-way valve allowing air from the mouth comparment into the eye compartment and perhaps one on the other side moving air back into the mouth?

That last bit about telling snorklers not to dive with it is probably important. I've been on a snorkel boat once. My wife and i were the only ones who had our own stuff. Everyone else grabbed masks/fins/snorkels from a bin and jumped in. I don't think they got any instruction, although I totally could have missed it as we were last minute additions. This was before I'd ever heard of or seen one of the now ubiquitious full face snorkel-masks. I'd kind of like to try one, just not bad enough to pay $50. Also the inability to dive down really kills it in my mind.