Scuba diving is a very specialized activity, and, like with any sport you would participate in, it can have a dramatic impact on your health if you do not take the proper safety precautions People who are interested in jet-setting to the islands or beach will need to consider some basic principles for before, during, and after scuba diving.
Is it safe to fly before or after scuba diving? Flying before scuba diving will not cause problems. (Source) However, divers should wait to fly for at least 12 to 18 hours after diving, or they may experience decompression sickness. Some divers will wait as long as 24 hours before flights or going to a high-altitude excursion like a mountain climb. (Source DAN)
The reason why scuba diving experts recommend waiting such a long period of time is that your body experiences a large amount of pressure during dives; this pressure can have a temporary effect on your body once you surface again, and is compounded when you climb to higher altitudes.
The Effects of Scuba Diving on Your Body
Scuba diving essentially puts your body in extreme conditions. When you dive in water over 15 meters in depth, your body will be compressed by a number of pounds per square inch (psi). As a result, your circulatory system works in overdrive to pump blood and oxygen to your cells. While diving, you also breathe pressurized air from a tank that will temporarily form gas bubbles in your body, which will disappear over time after surfacing.
As the pressure outside of your body increases during diving, the following happens:
- Your heart rate increases, resulting in higher blood circulation.
- Your body receives higher oxygen and nitrogen levels from the air tank you use.
- Any gas in your body is compressed into tiny bubbles in your muscles, blood, and organs.
When you rise up to the surface, those bubbles in your body will expand; the faster you rise, the bigger they get due to the reduction in pressure—to the point where they can be dangerous. This is why scuba diving experts recommend slowly rising to the surface at the end of a dive, or “gassing off”; doing so allows your body to begin releasing excess nitrogen naturally.
Once you are back on land, your body experiences less pressure:
- Due to there being less compression, more gas is expelled naturally.
- As a result, the body needs less oxygen pushed into it.
- Any gas in your blood will expand to normal levels.
Airplanes and Pressure
As a general rule, airplane cabins are pressurized, but they only go up to 11 or 12 pounds per square inch (psi). At sea-level, the pressure is 14.5 psi, but when you dive, the psi goes up the deeper you go. At 15 feet below sea-level, a diver can experience as much as 20 psi.
For that reason, divers often experience a large range of pressure between scuba diving, getting back to the surface, and then flying on a plane. If this change in pressure happens too fast, you are more likely to experience decompression sickness.
Decompression sickness (DCS) results from not allowing your body to expel the pressurized breathing gas naturally. It is caused by the tiny bubbles that are absorbed into your muscles and blood expanding too quickly due to a fast change in pressure.
This results in pain, sickness, vomiting, and diarrhea; in severe cases, it can lead to paralysis and sometimes death. Please consult a medical professional if you feel you are experiencing any of the following DCS symptoms:
- Joint pain
- Difficulty thinking clearly
- Extreme fatigue
- Tingling or numbness
- Weakness in arms or legs
- Skin rash
Not all of these symptoms have to be present for you to have decompression sickness, which makes it even more imperative that you wait for at least 12 to 24 hours before flying after scuba diving. Read more on treatment of DCS at DAN.
To avoid decompression sickness, scuba diving experts recommend that you go through the process of properly decompressing your body or “gassing off.” Of course, there are a number of other things you can do to avoid decompression sickness.
Tips to Prevent Decompression Sickness
While decompression sickness, or DCS, is easy to explain, it’s harder to remember when you’re caught up with the excitement of travel and a scuba diving experience. Great care needs to be taken when you plan a trip involving scuba diving and flying.
Here are some things you should avoid immediately after diving that could trigger DCS:
- Flying: It basically triggers DCS and has the potential to be deadly if you do not wait the proper 12-24 hours. The length of time you should wait before flying depends on the number of dives you take, and the dive depth (deep dives are considered to be dives over 15 meters in depth).
- Travel to High Altitudes: This includes driving up a mountain or hiking to the top of an inactive volcano. Be mindful when scheduling post-dive outings.
- Exercise: Your muscles will be rich with nitrogen bubbles, so you’ll want to plan a rest day after your dive.
- Get a Massage: Massages would be nice after a dive if it weren’t for those tiny bubbles jammed into your muscles and blood. Allow for a day of rest before receiving massage therapy.
- Take a Hot Bath or Shower: Doing either will only increase your blood pressure while preventing the release of nitrogen, again increasing health risks.
- Drink Alcohol: This will dehydrate you, which can act as a precursor to DCS. Stay hydrated!
Knowing When You’re Ready to Fly Again
In general, it is best to wait at least 12 to 24 hours after scuba diving before you get on a flight. However, the wait time could differ between divers. The following are some things to consider when determining if you have waited long enough to fly after a dive.
- Blood Pressure: First, you will need to make sure you don’t have any blood pressure or heart issues prior to diving because the activity will make your heart work harder than it usually does. Before diving, check your blood pressure to see where it stands and to get a baseline of your normal rate. Then, after diving, check your blood pressure again, and check it regularly. You’ll know you are ready to board a flight once your blood pressure reaches its normal levels and stays consistent.
- Tiny Gas Bubbles: While there’s no test to find out how you’re doing with expelling gas, you’ll know you’re doing it if you start to feel gassy. If you don’t release the gas before it’s time for your flight, you risk getting decompression sickness.
Post-Dive Pre-Flight Considerations
If you plan to fly post-scuba diving, you need to consider these final flying tips offered by the Federal Aviation Administration (FAA):
- Wait at least 24 hours between scuba diving and flying.
- You are at risk of altitude-based DCS if you fly on an unpressurized aircraft above 18,000 feet.
- You can have no symptoms of DCS and still be at risk of getting it due to the sudden loss in cabin pressure during a flight.
- Should you experience any symptoms of DCS or think you may have experienced a symptom of DCS on your flight, seek out medical attention right away.
While scuba diving is an exhilarating activity and can afford you some amazing one-in-a-lifetime experiences, great care should be used when taking scuba diving trips before flights. It is highly recommended that recent divers wait 12 to 24 hours before boarding a plane; ultimately, waiting the proper amount of time after scuba diving to fly will protect your health and ensure you are safe during your trip.