Elevation Matters, Plan Accordingly

You planned on diving on the Big island of Hawaii which is the world’s largest volcano and largest mountain in the middle of the Pacific Ocean. The only practical way to get there is by plane. But upon booking your dives you’re asked when you plan to fly home and then you remember. “Oh yeah!” I’m not supposed to fly after diving! But how long after diving can you fly? “I don’t remember! Isn’t that what my dive computer is for?”

Many people are not aware of the guidelines and even fewer realize that it’s easy to exceed the recommended altitudes by simply driving around the island.

aerial view of a dive boat cruising along the lava rock coast of the big island of hawaii
In some places like the Big Island of Hawaii, it’s easy to exceed the 2,000 feet elevation recommendation.

Kona Honu Divers is Hawaii’s top-rated and most reviewed dive operator. We’ve won Scuba Diving Magazine’s readers choice award for best in the Pacific and Indian Oceans. We take thousands of divers to see the Big Island’s beautiful reefs every year. One of the most common questions we ask is when you will be leaving the island. Many people are not aware of the guidelines and even fewer realize that it’s easy to exceed the recommended altitudes by simply driving around the island.

What are the Recommendations for Flying After Diving?

Never fear Kona Honu Divers is here to set things straight. Firstly, the rules are fairly simple but they do not only apply to flying. They also apply to driving. If you dive in the ocean (sea level) and then drive to almost any other part of the Big Island of Hawaii you will exceed 2000ft in altitude. In fact it’s possible to climb from sea level to 2,000 feet in about 14 minutes by car!


Flying After Diving Rules

  • 1 dive on one day – wait 12 hours . . .
  • Multiple days or multiple dives – wait 18 hours . . .
  • Mandatory Decompression dive – wait 24 hours . . .
  • . . . before exceeding 2000 feet or 600 meters elevation.

If you’re only doing a single dive on a single day it’s only necessary to wait 12 hours before going above 2000 feet (600 meters) in altitude or getting in a plane. If you’re doing multiple days of diving or more than one dive it’s recommended to wait at least 18 hours before flying. If you’re doing a dive in which your computer requires you perform a deco stop wait at least 24 hours before flying.

Where do these Recommendations Come From?

Research was conducted by Duke University funded by DAN (Divers Alert Network). Out of 802 trials there were 40 incidents of decompression sickness. There were no cases of DCS for surface intervals of 11 hours or longer for single dives less than 60 feet. For repetitive dives DCS only occurred with intervals shorter than 17 hours. A consensus was reached by the 2002 Dan Flying After Recreational Diving Workshop and the current guidelines were established.

What did the flying after diving Recommendations Used to Be?

Prior to 2002 the guidelines were more conservative. 12 hours for a single dive, 24 hours after multi-day repetitive dives, and 48 hours after decompression dives.

What if Scenarios

If you may be experiencing decompression sickness (DCS) symptoms it is recommended not to fly. It’s likely worse to fly with DCS than it is to develop DCS symptoms on a flight.

If you’ve just done a shallow dive and then plan to go to 1900 feet elevation it’s considered safe by the recommended guidelines, but what if you do a deep dive? Is it then safe to go to 1900 feet but not 2100 feet? It’s always best to err on the side of caution if you’re attempting to avoid DCS. Remember these are recommendations and they will not always be 100% certain or safe. It is still possible to get bent (DCS) when following all of the rules, however these guidelines have been put in place with lot’s of data backing them up.

In general it’s always better to wait longer before going to altitude. The longer you wait the lower the likelihood of decompression illness.

Decompression Dives

There is not good evidence or research for decompression dives so it’s recommended a diver take substantially longer than 18 hours before diving. So 24 hours is good but 36 or 48 or even 72 hours is even better! In general, when it come to why you can’t fly after diving the more time spent at depth and the deeper the dives, the longer a diver should wait before exceeding 2000 feet.

Frequently Asked Questions

Can You Fly After Scuba Diving?

The short answer is no, you can’t fly immediately after scuba diving. There is a recommended waiting period after diving before flying to reduce the risk of decompression sickness. See the flying after diving rules for specifics.

What Happens if You Fly After Scuba Diving?

The nitrogen that is off gassing from your body as a result of your dive accelerates its rate of off gassing. This is because the pressure surrounding the body is decreased as there is lower air pressure at altitude.

When a diver descends below the surface the nitrogen in the air they breathe gets compressed in their body tissues. This includes skin, blood, and organs. Much like CO2 in soda cans the pressure is held inside the body. As the diver ascends the nitrogen off gases by leaving the tissue often in the form of very tiny bubbles. If the divers ascends quickly the bubbles increase in size and quantity. Flying is like ascending from depth and allows more nitrogen to escape the body. This can result in the bends which is also known as “decompression sickness” or DCS.

How Long After Scuba Diving Can You Fly FAA?

According to the Federal Aviation Administration (FAA), the recommended waiting period after diving before flying is 12 hours for dives that reach depths less than 130 feet, and 18 hours for deeper dives. However, these are just guidelines and the actual waiting period may vary depending on factors such as the depth and length of the dive, as well as the individual diver’s response to diving. It is always best to consult with a dive professional or dive organization for more specific guidelines.

What Happens if You Dive and Fly in the Same Day?

If you dive and fly in the same day, you increase your risk of developing decompression sickness. This is because nitrogen gas from the air you breathe while diving becomes dissolved in your bloodstream. When you fly, the change in cabin pressure can cause the nitrogen to form bubbles in your bloodstream, which can lead to decompression sickness and painful symptoms such as joint pain, paralysis, and more.

What Happens if You Go Underwater and Fly?

The same principles apply if you go underwater and fly. The change in pressure from diving to flying can cause nitrogen bubbles to form in your bloodstream, increasing your risk of decompression sickness.

What Happens if You Don’t Decompress?

If you don’t decompress after diving, nitrogen gas will continue to be dissolved in your bloodstream. When you ascend too quickly, the nitrogen can form bubbles in your bloodstream, leading to decompression sickness.

What Not to Do After Scuba Diving?

To reduce the risk of decompression sickness, it is important to avoid activities that can increase pressure in your bloodstream, such as flying, diving, and driving in high-altitude areas. You should also avoid drinking alcohol, smoking, and engaging in physical activity after diving.

In conclusion, flying after scuba diving can be dangerous due to the increased risk of decompression sickness. To reduce this risk, it is important to follow guidelines for safe diving practices, such as waiting a certain amount of time after diving before flying, and to avoid activities that can increase pressure in your bloodstream. By following these guidelines, divers can enjoy their underwater adventures with peace of mind.

Questions?

We hope this guide helps to better explain why you can’t fly after diving but if you still have questions give us a call at (808)324-4668 or e-mail [email protected]. You can also speak to a medical professional at Divers Alert Network (DAN). They are medically trained and can answer all of your diving specific questions.

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