carey@uiucdcs.CS.UIUC.EDU (10/28/85)
When the wide-bore snorkels first came out they were supposed to make
things easier by providing less resistance to the air flow and enabling
the diver to get more air faster.
I just read in an article that a disadvantage is that it increases your
"dead air" space--that is, there is more air that does not get recirculated,
since there is a larger volume of air inside the snorkel.
Has anybody experienced a problem like this? What kind of tradeoff is
this? After all, it would be less tiring to have an easy draw of air.
I think I would rather have to take 10 easy breaths than 8 restricted
breaths for the same amount of oxygen, but I have never tried the
wide-bore style. I wouldn't like to black out from lack of oxygen (or turn
blue in the face)
--John Carey
-- {ihnp4,convex,pur-ee}!uiucdcs!carey carey%uiuc@csnet-relay.arpa
carey@CS.UIUC.EDUsandler@utcsri.UUCP (Howard Sandler) (10/31/85)
I don't think that the problem with wide-bore snorkels is "dead-
air" space. The air you exhale into the tube is still 16% oxygen and
makes up only a fraction of the air you inhale on the next breath.
The difficulty that I have found with wide-bore snorkels is the large
amount of water that drips back to the mouthpiece after clearing
them. Perhaps this is ddue to the larger surface area compared to
a smaller-bore snorkel.
Having said that, I still prefer a wider snorkel for the easier breathing
resistance. The rule I was taught in my NAUI course was to choose a
snorkel just wide enough to stick your thumb into. It has never failed me yet.
I would like to pose a question myself. I have always used snorkels that
bend immediately from the mouthpiec; that is, they don't have the classic
"J" shape that early snorkels had. I find that after clearing these snorkels
the drip-back arrives right at my mouth, causing me to choke on the next
inhalation. It seems to me that the true "J" -shaped snorkels would be
better, since the water would collect at the pit of the bend, rather than
at the mouthpiece.
Howard M. Sandler
Dept. of Electrical Engineering
University of Torontohogg@utcsri.UUCP (John Hogg) (10/31/85)
Another method of reducing dead-air space is adopted by the more macho
members of our underwater hockey league: they saw off their snorkels, so
that the end is at head-top level or below. The reason for this
modification is actually to reduce drag; a few leather-lungs types do
without a snorkel entirely. Ya gotta be tough.
Unfortunately, this has limited applicability to open-water diving.
Manufacturers design snorkels to keep the majority of wave-tops out of
the end, and expect their users to object to breathing water.
--
John Hogg
Computer Systems Research Institute, UofT
{allegra,cornell,decvax,ihnp4,linus,utzoo}!utcsri!hoggurlord@rruxc.UUCP (K Lotkowictz) (10/31/85)
In-reply-to: your article <12000005@uiucdcs> The biggest problem I've had with large bore snorkels is that they are harder to clear of water. (when blast clearing) My wife also has this problem, However, we both use them since breathing is easier. Ken Lotkowictz ihnp4!rruxc!urlord
atkins@opus.UUCP (Brian Atkins) (10/31/85)
I have had a wide bore snorkel (Tekna) for about 3 years and have had
no dead air problem. The one thing I did notice is that blow out
is harder and often requires a second blast to get some drizzle out
if the bottom. The problem ca be eliminated while snorkeling by
using the "puff" method. When on the surface on the way to scuba, however,
this can't be done.
I would think that prolonged snorkeling using only the blow method
would cause greater fatigue.
Brian Atkins ...{attunix, hao, allegra, ucbvax}!nbires!atkins
NBI Inc., P.O. Box 9001, Boulder CO 80301 (303) 444-5710barb@oliven.UUCP (Barbara Jernigan) (11/07/85)
> > The biggest problem I've had with large bore snorkels is that > they are harder to clear of water. (when blast clearing) True -- but the *easiest* way of clearing a snorkle is the most unbelievable. When surfacing, exhale a small bubble of air into the snorkle, as you tip your head forward to horizontal, the bubble pushes the water right out of the snorkle. It takes practice, but it WORKS! Meanwhile, learn to breathe through your teeth.....O-) <-smiley with mask o . o@ooo0 )\ ..oooo )\ \oooo \ Barb \ \ \oo )\ \o00 )\\ o000 .)_\\0000 .o)_o0000 .ooo00 o. .oo00 0o. .oo00 0o. .oo00000o. .oooo.
grunwald@uiucdcsb.CS.UIUC.EDU (11/14/85)
I use a wide-bore snorkel for underwater hockey, and I think you'll find that you use the snorkel & clear it more often in UWH than when diving. I like the large bore because of the easy breathing. Clearing is not much of a problem is you release air into the snorkel as you ascend -- this clears the water out as you break surface & leaves you with enough air to blast the snorkel to clear out the dregs. dirk grunwald university of illinois