28
hours, then a 12 hour surface interval before flying is recommended.
2) Following any dive that required a decompression stop, flying should be
delayed for at least 24 hours, and if possible, for 48 hours.
Since the 1990 UHMS guidelines were introduced, data from the Diver’s
Alert Network (DAN) was introduced that resulted in DAN’s position* that “A
minimum surface interval of only 12 hours would be required in order to be
reasonably assured a diver will remain symptom free upon ascent to altitude in
a commercial jet airliner (altitude up to 8,000 ft.). Divers who plan to make
daily, multiple dives for several days, or make dives that require decompression
stops, should take special precautions and wait for an extended surface interval
beyond 12 hours before flight.” Both the UHMS and DAN agree that, “There
can never be a flying after diving rule that is guaranteed to prevent decompres-
sion sickness completely. Rather, there can be a guideline that represents the
best estimate for a conservative . . . surface interval for the vast majority of
divers. There will always be an occasional diver whose physiological makeup or
special diving circumstances will result in the bends.”
The Time to Fly display provides a way to choose your own degree of
protection by providing two twelve-hour countdowns after the dive. The first
display begins four hours after the dive and is shown in the PDPS, displaying
the word “FLY” with a countdown from 20 to 12 hours. After 12 hours, the
dive counter resets to zero and Surface Mode is shut down. A continuously
displayed countdown timer now begins from 12 hours to 0. Because the Pro
provides two 12 hour countdowns, you can choose whether to fly after twelve
hours of surface interval or wait additional time to add greater protection.
* excerpted from “DAN’s Current Position on Recreational Flying After Diving”