I guess, maybe. I cave dive usually for a little over an hour average depth
around 100' on 32% Nitrox. I have a deco obligation of about 5 min on 100% O2 at 20 ft. Five min. of deco is nothing, a safety
stop is three min.
I have to assume these guys were coming off a deep job already saturated, Helium cost me around .40 cents a cubic ft. My SAC rate is .67 swimming, so at 300' or so breathing 10/70 I'm going through about $2 a minute of helium. Helium ain't cheap
, so I don't understand it's use either on this job, unless maybe they were coming off a deep job?