Northwest Dive Club

60south wrote: For instance, if I go from 6000ft to 13000ft prior to the dive in the space of, say, 4 hours, what is my residual nitrogen loading? Specifically, how should I adjust my dive plan to compensate?

Nothing IMO. On the actual dive your tissue will have a tiny amount of "pre-loaded" inert gas. That is just before you descend you will still have a slight overpressure gradient in your longer tissues and this in theory could reduce your allowable no-deco time. But in practice it won't make a bit of difference. 4 hours is actually a fairly long surface interval after all. All of your controlling tissues will be at ambient and you can just plan the dive as you wish for the applicable altitude.

I have been lurking very intently on this thread. I regularly dive two or three dives in a day and drive over Stevens pass, elev. 4,050 ish' to get home with no I'll effects. My home is at 2,650' here in beautiful Eastern Washington. The one time nitrogen got the better of me I knew before getting above 200'. It would be nice to see more definative information about this topic.