Theres some great info in this thread, but two factors I havent seen mentioned to reduce the risk following altitude dives, and when flying or driving to higher altitudes after a dive.
While working ski patrol, mountain rescue, doing altitude dives in Colorado, and flying as a charter pilot, I was always surprised at how many people let themselves get dehydrated at altitude. Dehydration is certainly a factor in susceptibility to DCS, and at altitudes where youre losing fluids faster than at sea level many people dont drink enough to make up the difference. Dry SCUBA air can take enough moisture out of your system without the added loss from the altitude so even if youre staying well within the bounds of the NOAA altitude tables make sure youre not dehydrated or they wont help you.
Not that I recommend it, but Ive been pushing the tables for flying after diving for years, but I give myself an extra margin. I keep two portable O2 tanks in my plane and if I think I may need to fly after diving I take one with me either on the boat or have it available as soon as I get ashore. As soon as possible after my last dive I breath O2 (from a mask, not a cannula) for about 30 minutes, and if I do fly before the tables say I should I go on O2 for another 30 minutes before flying. I also stay as low on my flight as I safely can.
I took one good hit of the bends in the joints back in 1972 (when I was young, dumb, 9 tall, and bulletproof). I had regularly been flying back to Florida from the Bahamas 5 or 6 hours after diving, but Id never climb to more than 3,000 until one afternoon I got caught in some bad weather. Without thinking about the diving, I started climbing to 10,000 to get over some rain clouds and at about 8,000 all at once I thought my knees, elbows, and hands had caught fire from the inside. I declared an emergency and began descending almost immediately and by the time I got back down to about 5,000 I was sore but the sharp pain had gone away. By the time I landed at St. Lucie County I was feeling fine, but the medical crew put me on O2 for an hour, and I spent the night there before flying home the next day.
While working ski patrol, mountain rescue, doing altitude dives in Colorado, and flying as a charter pilot, I was always surprised at how many people let themselves get dehydrated at altitude. Dehydration is certainly a factor in susceptibility to DCS, and at altitudes where youre losing fluids faster than at sea level many people dont drink enough to make up the difference. Dry SCUBA air can take enough moisture out of your system without the added loss from the altitude so even if youre staying well within the bounds of the NOAA altitude tables make sure youre not dehydrated or they wont help you.
Not that I recommend it, but Ive been pushing the tables for flying after diving for years, but I give myself an extra margin. I keep two portable O2 tanks in my plane and if I think I may need to fly after diving I take one with me either on the boat or have it available as soon as I get ashore. As soon as possible after my last dive I breath O2 (from a mask, not a cannula) for about 30 minutes, and if I do fly before the tables say I should I go on O2 for another 30 minutes before flying. I also stay as low on my flight as I safely can.
I took one good hit of the bends in the joints back in 1972 (when I was young, dumb, 9 tall, and bulletproof). I had regularly been flying back to Florida from the Bahamas 5 or 6 hours after diving, but Id never climb to more than 3,000 until one afternoon I got caught in some bad weather. Without thinking about the diving, I started climbing to 10,000 to get over some rain clouds and at about 8,000 all at once I thought my knees, elbows, and hands had caught fire from the inside. I declared an emergency and began descending almost immediately and by the time I got back down to about 5,000 I was sore but the sharp pain had gone away. By the time I landed at St. Lucie County I was feeling fine, but the medical crew put me on O2 for an hour, and I spent the night there before flying home the next day.