cold water/sealed regs

[chrisw]

obviously i am not an expert at this. i am just
stating what the dive operators require. i think
its a question of economics and simplicity.

they have to haul all the gear and supplies from
europe to south america and then to antarctica.
i am guessing that pretty damn expensive to tote
argon and nitrox.

they supply the y valves, tanks (compressed air) and weights.
i think this keeps it simpler for them to manage/repair/maintain the
equipment.

in addition they do specify that dives should be
no deeper than 60 ft MAX. and 30 min or less.
the water is 28F and there is virtually no way to
airlift a person to New Zealand for decompression.

while i realize that simplicity and rules do not make for
safety, i think it sure helps them keep a better
handle on their divers and their equipment needs/safety.

i remain unconvinced that not using nitrox or argon
constitutes so much risk as to make it unsafe to dive
with them.