Question ?  From: Gustavus School, Gustavus, AK

Do you have a decompression chamber of any sort available to you?  If you did have access, how close is it at any given time and how long you would have to be in one if there was a situation that called for it?  I suggested that it would probably depend on the situation, and they were wondering if you could give them a scenario.

This is an excellent question, very unexpected!!

(Bob  answering). I chose to answer this question because I always have been very interested in dive physiology.

We do have a decompression chamber, it is located in the medical building just in the center of McMurdo Station. It's a very nice chamber, it holds 2 subjects comfortably along with one attendant. There is an air lock for changing attendants as well as a small air lock for transferring items. 

We carry O2 to every dive site and in the event of a dive emergency we would administer the O2 and then transport the diver by ground back to the chamber. We don't have too many dive sites that are more than an hour from the station.  When we are at the New Harbor field camp there is no way to drive home. So we have several big bottles of O2 that would last for a long time. If we had an event that might require the chamber the diver would be flown as soon as possible by helicopter back to the station. Since flying can aggravate DCS (decompression sickness) the pilots would fly at or below 300 feet. The flight back to the station is about 30 min. and the subject would be on pure O2 the entire time.

As for how long a treatment in the chamber would take - this does depend on the extent of the DCS (or in some cases suspected DCS). Chamber treatments are performed even if DCS is only suspected. The Navy has developed chamber decompression tables. Each table is a predefined treatment. Table 6 is the standard treatment for suspected mild type1 DCS. 

I hope this not only answers your question but generates more technical questions about how we perform in this environment.