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Adam33port17
01-05-2010, 09:13
I just got certified last fall and my first dive is going to be in Kauai in March. I know the rules about flying after diving and they say that after diving in Kauai not to go to Wiamea Canyon due to its elevation. My question is, just how high can I go after diving? Thanks and great to be here!
Adam (land locked in Iowa)

rayaa3
01-05-2010, 09:42
Hello, and welcome..

you should get to know the DAN website, they have great resources

DAN Divers Alert Network (http://www.dan.org)

as to your specific question, I've heard 1000ft above sea level quoted to me, however, Dan has an article which would lead me to more conservative advice...basically treat this like flying...if you do 1 single no decompression dive...wait 12 hours, multiple dives, 24 hours....anyway...from the DAN report:

http://www.dan.org/medical/report/2005DCIReport.pdf


2.7 Altitude Exposure After Diving

Exposure to altitude higher than 700 feet (210 meters) soon after
diving is considered an additional decompression that may provoke
DCS in some divers who otherwise would not be affected. At
the time when the PDE study was designed there were few data
regarding the post-dive time that a diver should wait before safely
ascending to an altitude. That was the reason that PDE requests
divers to report altitude exposure within 48 hours post-dive.

scubadiver888
01-05-2010, 10:59
There is no single, correct answer to this question. Getting bent involves a lot of factors. How deep were you? How many dives did you do that day? Have you been diving multiple days? What pressure group are you in when you start ascending to a higher altitude?

The more you dive, the higher the risk of DCS. The deeper you dive, the higher the risk. The higher your pressure group when ascending to a higher altitude, the higher the risk. Add all these together and the risk increases even more.

Read the stuff from DAN. This will be more of a 'feel' then an exact science.

I know I have gone to 1000 feet after a 4 hour surface interval diving multiple dives over multiple days to 100 feet or deeper. I was in pressure group X when I finished my last dive. I don't have my tables so I don't know where a 4 hour surface interval would have put me. Still the multiple dives to 100+ feet over three days of diving increased my risk. I, normally, won't have done it but I never thought about the fact that I lived in the penthouse of a skyscraper and went home right after a long weekend of diving (fortunately it was 4 hours away from my home).

My instructor was not as lucky. She went diving in Alberta (east of the Rocky Mountains) with some friends. Drove home right after the last dive. She lived in British Columbia (west of the Rocky Mountains). Not sure what the elevation of the road she took was but it was easily 4000 feet. She got skin bent. No ill effects as far as she can tell and that was many years ago.

Bottom line, if you can, wait at least 6 hours before going to elevation. If you can wait 12 hours, I feel, you could go to 500 to 1000 feet safely. If you wait 24 hours, I feel, you should be fine to go higher. Regardless, you could get bent going to 200 feet after some aggressive diving.

Learn about all the things which contribute to DCS. Think about how many things you have going against you. If you have a lot of factors going against you, wait as long as you can before going to elevation.

Darrell