View Full Version : Swim Snorkels and CO2 ?

February 18th, 2007, 07:17 PM
I just heard from someone who used to be a dive master and is now in medical school (not here, he's in the States).

He has told me that there is a correlation between using a snorkel and CO2. What he said was because when a swimmer or snorkeler breathes in and out and because of the width and length of the snorkel tube, that CO2 remains in the bottom of the snorkel so when the swimmer/snorkeler takes each breath, he is inhaling the remains of CO2. This is not a good thing.

Is this why, maybe, that when using a snorkel it appears a swimmer/snorkeler can't get a good breath? I also know that because of the small tubing size, it is hard to really hard to inhale a lot of air, or at least that has been my problem. But CO2?

Is this why when using a snorkel for swimming or snorkeling, breathing can be difficult for some? I know Warren said he uses one, I'd be interested to hear if he has found any problems with using it.

Anyone else?


February 18th, 2007, 08:30 PM
This is my bread and butter, my home turf. Here is the simplistic answer. To go deeper type in "dead space" in your google and see all the answers. billy fanstone


Redbird Alum
February 18th, 2007, 10:54 PM
Billy -

Great article! I first learned about this topic when I was treated for chlorine gas inhalation in my teens (really nasty lifeguarding experience!). The doc's in the ER had a dickens of a time getting my lungs cleared because every inhalation/ehalation hurt like heck, but they really pushed me to "exchange" as much as possible once they got me on the oxygen bottle. Similar to the exercise they use to help prevent pneumonia when you're on an extended hospital bed stay.

Thanks for the link!

February 18th, 2007, 11:08 PM
I got a snorkel about three weeks ago. I havn't had any problems with it. But it is harder to get a good breath. I only use it for drills like one arm free and catchup drills so I'm not really breathing that hard becuase its low effort. A snorkel is definatly good for drills, I like it.

February 19th, 2007, 06:45 AM
I use a snorkel to swim when paying close attention to my stroke, specially the front crawl. I also use it to do leg drills, including the dolphin kick. And, once a year, I use it for snorkeling! The snorkel is no problem for its primary use as when snorkeling for viewing or for spearing fish, one does not swim fast enough or at a level where oxygen is a problem. The snorkel is a device that will permit you to look down and see the fish or whatnot without having to take a breath losing your eye contact. When you come up for air you blow through the water in the tube and take a breath, so the C02 retention isn't really an issue. One does get tired after a long time of snorkeling, even though you are hardly moving in the water, just gently using your fins, and I believe that is due to the residual C02 that creeps up on you through all that dead space. There is no dead space added when using a breathing apparatus(SCUBA) as the valve is at your mouth, i.e. you don't expire through any resistance. There is a competition, mostly by firemen or armed forces guys, where you are allowed snorkels, masks and fins. You cannot use your arms, which stay a if you were at attention. These guys usually swim up to 3 kilometers using only their legs. The main distraction is keeping their bearing, in the dark waters of lakes. But those guys are fast and come in close behind the normal 3 k swimmers. billy fanstone

February 19th, 2007, 01:27 PM
I use a snorkel when I swim on my own--since during practices the intervals tend to be too fast for me to catch my breath using the snorkel.

They advertise that the use of a swim snorkel consistently (aka...during all types of sets...not just kick and drill) will enhance your lung capacity or build up your lungs (not the technically advertisment slang). I definatly do feel like I have a harder time catching my breath when I am using it, but it also I do feel made me less of an air gulper without the snorkel!

October 14th, 2007, 02:24 AM
I just got a snorkel and have only used it a couple of times so far. Last night I tried breathing out with my nose and in with my mouth so there would be no CO2 in the tube. That made a lot of bubbles rising up around my eyes and it sounds very loud underwater, and it takes some concentration to breath that way so it's kind of weird. I'm still experimenting with it.

October 14th, 2007, 05:32 AM
The breathing out through your nose or through the snorkel wouldn't make any difference. The dead space is there anyhow because it is a function of the distance of the end of the snorkel to the larynx or pharynx, forget which. The C02 accumulates because of the exchange in the breathing in, not in the breathing out. The snorkel is only good for three things: snorkeling, which would be to look down while breathing without moving your head (and maybe diving to get some fish), which is the original reason for having a snorkel, or for swimming in a pool without moving your head to breathe, or for "exercising" your respiratory system (not probable) making it harder to breathe in air (making it easier once you get rid of the darn thing?). billy fanstone