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Wetsuits for Caving
By John Ganter, NSS 22870RL
Cold is a major threat to cavers. Nothing makes you cold faster than
being wet. So neoprene wetsuits, with their ability to insulate us
against wet and cold, have made a lot of caving possible. This article
discusses how wetsuits work, the major styles available, and how fit
for caving is very different from diving. John Ganter, article author,
also gives some tips that he has learned over the years, and conclude
with a discussion of how wetsuits fit into the caver's arsenal along
with alternatives.
How Wetsuits Work
Organisms, cavers included, lose heat in two main ways: conduction and
convection. Water conducts heat much better than air, so when your skin
gets wet you start to get cold. The water also begins to evaporate,
which takes still more heat from your skin and leads to convection
losses.
Neoprene works by creating and maintaining a thin layer of
body-temperature water next to your skin. This water does not move away
from you, which would carry heat, and very little cold water moves in
to replace it. There is some leakage around wrists, zippers, etc., but
this is relatively small. The neoprene rubber is also a good insulator,
beacuse as a closed-cell foam it does not get water inside it, like a
frabric does. Neoprene also acts as a wind and vapor barrier to reduce
convective heat losses. It provides moderate abrasion resistance, some
padding, and a bit of flotation.
However, sometimes your body produces excess heat that the neoprene
holds in -it keeps your sweat in the same way it keeps cold water out.
With divers this is not much of a problem, since they are completely
immersed. Also, divers usually don't have to exert themselves as much
as a caver doing a hard climb. So cavers can overheat in wetsuits, and
ways to reduce this problem are discussed below.
What about drysuits? Drysuits have been tried for caving, but they are
even less breathable than neoprene and are prone to punctures in caves.
Then they become water bags with no insulation and negative buoyancy.
Styles of Wetsuits
Pants: Pants come up to the waist. Cavers sometimes wear pants alone if
they will be wading. They will generally stay up on their own.
Farmer John: A "Farmer John" is a bib overall, resembling what a
stereotypical farmer wears. It comes up over the belly, and then
suspenders go over the shoulders. Cavers sometimes wear a Farmer John
alone, which is less constraining for the arms and shoulders than a
jacket.
Jacket: A jacket extends from the waist level and has a zipper up the
front. It has long sleeves.
Beaver Tail Jacket: a jacket with a flap of neoprene that goes between
the legs and connects to the front with turn-buttons, like a diaper. It
has a zipper that runs up the center.
Step-in Jackets are a newer design that include shorts. They have an
off-center zipper that runs up the right side from thigh to neck. You
step into the left leg of the shorts, put your arms through the
sleeves, then zip up the right side which first closes the right leg of
the shorts and then the side of the jacket.
Shorty: a full suit, but with no arms or legs. It provides warmth to
the trunk, without affecting flexibility.
Surfer Suit: a thin wetsuit that one enters through a long back zipper.
Divers like Farmer Johns and step-in jackets because they get a
double-layer of neoprene over their middle section. For caving, the
author prefers plain pants and a beaver tail jacket because only the
crotch area has two layers, leaving other areas more flexibile. It is
also very easy to undo the beaver tail to relieve oneself, and it is
easy to take the whole jacket off to put a shirt on underneath.
Sources of Suits
Off-the-rack Suit: If your body shape and dimensions are statistically
similar to the diver population, you may be quite comfortable in a
pre-made suit. You can try these on at dive shops, and you should be
able to find a table of dimensions. But keep in mind that the height
and weight given is for diving use, not caving. You need a
much looser suit than a diver would wear. Otherwise, you will be
miserable.
Custom-fitted Suit: Custom suits tend to be more expensive
than off-the-rack suits (although the Skin Diver suit is an exception).
With the assistance of a close personal friend, you take a large number
of measurments to fill out the order form. A suit is then made to fit
you uniquely.
Used Suit: Used suits of unknown pattern and dimensions can show up in
various places, including mail order. You usually have to try them on
unless they are a known brand and size that you are familiar with.
Fit is Important
Most wetsuits are marketed to divers, but cavers are not divers. We
walk, crawl, and climb on trips that last longer than most dives.
Are you mostly going to swim in cold water, or are you going to walk,
crawl, and climb with occasional immersion? Of the latter, you want a
suit that is much looser than a diver would wear. Otherwise, you will
work hard just moving. This will take a lot of energy, and it will make
you overheat.
If you get a custom-made suit, it is important to explain to the maker
that you will be walking, crawling, and climbing in this wetsuit. Don't
try to fudge your measurements. It is the author's opinion, from his
experiences, that it is is much better to give the experts accurate
dimensions and tell them what you need.
What Thickness of Suit?
The "Standard" US caving wetsuit is 3/16 ich (4.7mm). A 3/16-inch suit
generally works well for crawling and climbing with intermittent
immersion in the Virginias (in the 40°Fs) and long immersion in
Kentucky (in the 50°Fs) and the highlands of Mexico. In New
England, Canada, and the Rockies, 1/4 inch (6.5mm) is more common. Ask
cavers in the areas where you plan to use your suit.
Surfer suits are usually 3mm thick. Many cavers now use surfer suits in
warmer situations (warmer cave, more active trip, etc.). Often they are
worn under an oversuit, since they are more flexible and less durable.
Unlike diver suits, surfer suits are mass-market items which makes them
cheap and widely available both new and used.
Surfer suits are thin, so fit is less critical and the stiffness of
cheap neoprene "blend" (see "Types of Neoprene," below) is less of a
problem than in a thick diver suit.
Avoid one-piece or hard-to-remove wetsuits. You need to be able to
attend to bodily functions without assistance. Thin surfer suits may
work, but you may need assistance pulling down the back zipper. Also
note that plastic zippers are more resistant to mud clogging; avoid
metal zippers. There should be a strip of neoprene behind the zipper to
prevent skin and other sensitive personal parts from getting stuck in
the zipper.
Factors for a thicker suit:
-You are naturally "cold-blooded" or have low body fat.
-You expect lots of immersion
-You expect lots of slow surveying or belaying
Factors for a thinner suit:
-You are naturally "warm-blooded"
-You expect more hard climbing, long crawls, etc.
Most neoprene is now lined with nylon on the inside. This is
comfortable for putting on the suit ("donning") and for wearing. Nylon
on the outside gives a bit more abrasion resistance, but also increases
stiffness. Some neoprene is now "plush" lined. It looks comfortable,
and it may allow sweating when out of the water.
Neoprene is of two main types. Rubatex is the classic US-made brand
used by professionals; blends are the new, cheap, less-stretchy
varieties. These are discussed in greater detail below.
Clothing Over the Suit?
Some cavers wear coveralls, rubber jackets, or shorts over their
wetsuits. The thin surfer suits are well-suited to wearing under
coveralls, both to protect the suit and provide more warmth. What to
wear depends on local conditions (cold, abrasion) and how worried you
are about suit damage.
Plain wetsuits look good in photos, since they accentuate the human
form more than baggy clothing.
John has always liked an unencumered 3/16-inch suit, with kneepads and
a pair of old shorts to protect the beaver tail if high abrasion is
expected.
Accessories
Extra zippers, such as ankle or wrist zippers, should be avoided. They
tend to be smaller than the main zippers and are very vulnerable to
clogging with mud.
Some cavers, male and female, wear nylon stockings under their wetsuit
pants. Stockings can help to get your wetsuit on, reduce chafing, and
add a bit of warmth when you are out of the water. There are also thin
Lycra tights sold at most dive shops for wearing under wetsuits.
If you experience chafing, especially on long trips, try applying
A&D ointment before the trip. It can get a bit "gunky" on the
nylon lining, but it can be removed with baby shampoo and a scrub
brush. The difference in comfort can be very significant.
Kneepads installed on wetsuits tend to be too thin for caving use.
Basketball kneepads, Rockmasters, or Bomber pads are all popular.
Wetsocks are very important! Many cave trips involve getting your feet
wet, and nothing else. Wetsocks will make a huge difference in your
comfort and endurance. Wetsocks can be purchased for less than $10 at
Wal-Mart in the hunting and sporting goods section.
Neoprene gloves can be nice in very cold conditions. They are very
abrasion resistant compared to plastic-over-fabric, but are difficult
to remove such as for surveying. These cost less than $10 at Wal-mart.
Hoods are sometimes worn for cold water and/or long immersion. They
reduce the shock of immersion if you like to free-dive sumps. They are
also constraining and reduce hearing. Keen hearing can be important for
team communication in low-airspace situations. A balaclava is often a
more comfortable option.
A synthetic balaclava, cap, or hood will make a big difference in
comfort. After you get out of the water, pull a balaclava out of your
helmet or Nalgene bottle, put it on under your helmet, and you'll be
ready for a long survey trip. PolarTec is especially warm and
comfortable.
A synthetic long-underwear top can make a big difference in comfort,
and it's easy to put on compared to pants. Make sure it fits under your
wetsuit, then stuff it in a Nalgene bottle or multiple plastic bags.
After the trip
You're wet! The author suggests having a mat to stand on, a jug of
water to wash off the mud and for emergency zipper flushing, and a
towel for wiping down. A heavy duty 3 or 4-mil plastic bag is good for
dumping the muddy pile into.
A scrub brush is handy for the inevitable cleanup. A large
front-loading washing machine does a good job on wetsuits, but leave
the laundromat the way you found it! Harsh or heavily perfumed
detergents might cause problems such as itching for some individuals
the next time the suit is worn. You can but special detergents from
dive shops that claim to remove that amazing, pungent aroma of a
well-used wetsuit.
Wetsuits or Oversuits
Back in the 1970s, things were simpler. For most caving, you wore
cotton and some wool. For wet caving, you wore a wetsuit. Today, there
are more options.
The problem with wetsuits is that they have narrow ranges between
hypothermic, comfortable, and heat prostration. Why? It must be because
they interfere with our natural thermoregulation, mainly sweating.
Meanwhile, oversuits (synthetic coveralls) and underwear (especially
PolarTec polyester) are improving. PolarTec is especially good at
holding heat while wet, then draining down quickly and letting sweat
and heat escape. So cavers are now carrying extra insulation in plastic
bags through wet crawls and ear-dips, then putting it on when they
reach the other side. The pool may make them gasp for a few minutes,
but hours later when they are surveying slowly through a long crawl
they don't miss their wetsuit.
So wetsuits have their place in the project caver's arsenal, but there
are more options than ever.
Sources
Local dive shops are usually very expensive, but for the first-time
buyer they are a place to look at, feel, and try on the various styles.
You may even be able to pick up a bargain. Ask other cavers for
recommendations.
Types of Neoprene
There have been some significant changes in neoprene over the past few
years. Wetwear, a wetsuit manufacture and distributor, makes the
following comments:
"Several years ago most wetsuit manufactures began using neoprene
blends. They are adequate for watersports such as windsurfing and water
skiing where the wearer stays at surface level (or just above the
surface if they're good). Many of the blended suits have a one way
stretch, and their greatest amount of stretch is limited to one
direction. Depending on which way the material is used when
constructing the suit, it could mean that it stretches laterally when
you put it on, and has little flexibility should you raise your arms,
have a wide kicking stance, or put on a few pounds."
More information on neoprene, including the four grades of Rubatex, is
available at the Wetwear website at www.wetwear.com.
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*Credit is given to John Ganter (22870RL) and the National
Speleological Society NSS, for the above information which was
originally published in the NSS News, Vol. 58, No. 4, April
2000.
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