Most divers know air travel immediately following a scuba dive can lead to decompression sickness. But did you know there are other après-diving rules?
First, let’s review those rules about flying after diving. As you learned in your PADI® Open Water Diver course, it’s important to wait 12-18 hours after diving before traveling on an airplane. The preflight interval varies depending on how many dives you made.
Flying After Diving Guidelines from Divers Alert Network (DAN):
The following guidelines apply to air dives followed by flights at cabin altitudes of 2,000 to 8,000 feet (610 to 2,438 meters) for divers who do not have symptoms of decompression sickness (DCS).
• For a single no-decompression dive, a minimum preflight surface interval of 12 hours is suggested.
• For multiple dives per day or multiple days of diving, a minimum preflight surface interval of 18 hours is suggested.
• For dives requiring decompression stops, there is little evidence on which to base a recommendation and a preflight surface interval substantially longer than 18 hours appears prudent.
To err on the side of safety, many divers plan a 24-hour surface interval and spend their time exploring topside attractions. Here are a few other activities divers should avoid at the end of their diving holiday.
Activities to Avoid After Diving
Enjoying the view from a mountain top – Driving to the top of a 3,048 metre/10,000 foot mountain to snap some pics puts you at the same risk for DCS as flying in an airplane. Cabin pressure in an average commercial jet is equivalent to being at 1800–2400 metres/6000–8000 feet above sea level.
If simulated altitude puts you at risk for DCS, it follows that actually being at altitude is also risky. That said, people do dive at altitude and there are special dive tables to follow. Learn more about altitude diving.
Ziplining – Ziplining as an activity is fine, the concern is altitude. Many ziplining activities occur in the mountains. Confirm the altitude of your ziplining destination before you book, and zip with caution.
Deep Tissue Massage – What? No massage? Relax and breathe. Here’s the good news, according to DAN, “massage has not been confidently associated with…cases of DCS.”
Experts caution against deep tissue massage, but a gentle relaxation massage is probably fine. The two main concerns with deep tissue massage are:
– Increased blood flow might lead to bubble formation
– Muscle soreness that might cause soreness which can lead to misdiagnosis (or delayed diagnosis) of DCS.
Relaxing in a hot tub – As the body warms up and circulation improves, there is an increased chance of bubble formation. According to DAN:
Since the solubility of gas is inversely related to temperature, tissues will hold less in solution as they warm. Warming tissue with significant loads can promote bubble formation. Since the warming of the superficial tissues precedes the increase in blood flow, such bubbles can become problematic before the circulation can remove them harmlessly.
Intense Partying – Drinking a lot of alcohol can cause dehydration and delayed diagnosis of DCS. If you want to unwind with a few adult beverages, first drink lots of water, then enjoy in moderation.
If you’re a scuba diver and a freediver, many in the freediving community recommend applying the flying after scuba diving guidelines:
• After a single no stop dive, wait 12 hours before freediving.
• After multiple no stop dives, or dives over several days, wait 18 hours.
• After a dive requiring a decompression stop, wait 24 hours.
• Wait longer if directed by the manufacturer of your dive computer.
Flying After Freediving
The (US) National Institute of Health (NIH) reports at least 90 recorded cases of DCS following repetitive breath-hold dives. The “deepest man on earth,” freediving world record holder Herbert Nitsch, suffered DCS and was nearly paralyzed for life. The relationship between DCS and freediving is not widely accepted or understood; however, both DAN and the NIH recommend freedivers consider the risk of DCS following multiple deep dives and take precautions including:
– Long surface recoveries (3-4x the length of your dive)
– Don’t dive more than a combined depth of 120 metres (393 total feet) in one day
Because there is (essentially) no data for flying after deep freediving, wait 18 to 24 hours after making deep freedives before getting on a plane. Many in the freediving community use a four to six-hour pre-fly interval because freedivers remain at depth only briefly and the 18-24 hour recommendation is based on research with scuba divers.
Dissolved nitrogen isn’t a major concern for casual snorkeling to shallow depths. But, it is potentially a concern for constant weight freedivers who are also scuba divers. Don’t participate in recreational open water or constant weight freediving after scuba diving on the same day.
Regardless, the longer the interval between diving and flying, the lower the DCS risk. Many of the world’s best freediving destinations have a lot to explore topside!