Cool Fix is a new player on the UK market. Part
of a much larger Scandinavian group that has been in business for
four decades, its field is protective clothing. Clients have traditionally
been the military, including special forces, the emergency services,
and commercial divers. Cool Fix is now offering its product line
direct to recreational divers, branded under the name KLIMA Sport.
It's Thermodynamic jumpsuit uses a two-layer cloth
construction, with special vertical channels between the layers.
Once you are locked into your drysuit, there is normally nowhere
for the perspiration to evaporate to. If the perspiration soaks
the undersuit, it will quickly chill the diver. The Thermodynamic
ensures that perspiration is kept away from the diver's body so
that he or she remains dry and thereby conserves heat. Suits for
recreational divers cannot generate heat. They can only slow heat
loss. Air is a poor heat conductor and slows the transfer of heat
from the diver's body towards the cooler water which is in contact
with his drysuit. The special baffling in the Thermo traps air and
slows head loss.
The bottle green Thermo is very easy to put on
and features a full-length, centre, double-ended zip which can be
used as a relief zipper if you are the right sex and have the right
drysuit! The smooth outer surface makes it easy for the drysuit
to slip over it. I tested the suit over bare skin and found the
towel lining very comfortable and non-irritating.
The Thermodynamic is remarkably thin and supple,
compared to my normal lightweight Thinsulate. I tested the Thermo
over four dives and two days at Stoney Cove. I used my usual membrane
dry suit, so the only insulation was provided by the Thermo.
I must admit I had misgivings. It looked too thin
to be effective! So, I entered the water with some trepidation.
Above the thermocline, the water was in the mid-60¡s and I
was perfectly warm thoughout. I was observing fish and shooting
pictures, so for much of the time I was moving very slowly, or was
static and not generating much heat. We were finishing the dives
after around 70 minutes because we were running low on air. I never
On a dive to 35m the water was in the mid-40¡s.
I got cold quickly. Normally I would wear my lightweight Thinsulate,
thermals and perhaps a cloth undersuit for these temperatures. However,
I warmed up quickly at my safety stop and spent a further 40 minutes
cruising the shallows.
Overall, I liked the Thermodynamic. Compared to
Thinsulate, it is much less bulky and restrictive, making it easier
and less tiring to don and doff or swim in. Unlike some woolly bears,
it is comfortable on bare skin and does not leave a debris trail
of fluff that can interfere with valves.
As claimed by the manufacturer, I stayed dry. Conditions
were very favourable on the surface, so I did not test it for windchill.
I do not feel that the suit is suitable for cold
water diving as a stand-alone undergarment under a membrane dive
suit. For extremely cold water diving under a neoprene drysuit,
which provides integral insulation, it might well be ideal. I use
my drysuit for diving in the Med and the Red Sea and the Thermo
would be perfect for my needs, especially as it is light and compact
to travel with. For summer diving in the UK and much of Europe,
it would also be excellent. I would use it in combination with other
garments for cold water diving.
I have some minor personal criticisms. I would
like hand-warmer pockets, and a place to store keys and change.
That's about it, for quibbles. There are also none of the usual
thumb and foot loops. I did not find this a problem, but others
have commented on this. I tucked the legs into my socks, and held
the wrist cuffs as I pulled my drysuit on. Anyway, thumb loops can
I started out with very negative feelings about
using such a seemingly thin suit in cold water. I expected to freeze.
Appearances can be deceptive. My expectations were quite wrong.
From Cool Fix International Ltd, Knutsford, Cheshire,
01565 654906. Price £99 including p&p and VAT. Sizes:
small to xxxl.
W e would like to emphasise that the limitation
of the insulating properties of the garments are linked to the ability
of the cloth to absorb perspiration. If the garment becomes soaked,
you will have a cross-wire effect between the cold water outside
the drysuit and the diver's body. Warmth will travel 28 times faster
through water than through air. Any cloth will have a limited absorption
capacity which, however, can be improved by the addition of a cotton
garment on top of the undersuit when diving in extremely cold conditions.
As for the comments on missing pockets, this garment
has been designed for technical divers who have never mentioned
We do have in the product range a two-piece tracksuit
in a slightly heavier cloth. This is not as tight-fitting as the
one-piece suit that is tested here, but would, we would have thought,
be the last word in thermals for recreational divers as they can
also be used as leisure wear.
This particular suit was developed for the Scandinavian
fire brigades. Their staff wear nothing but this clothing while
on standby and when the alarm goes they simply put on their Goretex-lined
Nomex protective suits.