Flying after diving

[k954triniz]

I know flying after diving is a big no no. But when people think of flying they think of a commercial jetliner that goes up to 32,000 ft and higher. I am a small private airplane mechanic like the little cessnas and pipers. Today I had to refuse to go Bahamas to change a part on one of the planes I work on. I would have been flying for about an hour and wouldn’t go above 10,000ft due to the aircraft not being pressurized. I ended my dive in which I dove to 110ft at 11am yesterday and would have been in the air around 8am today. Can anyone advise me on if that would have been an issue. Also if even going to 10,000ft would even be an issue right after the dive.

 

[JackOfDiamonds]

It's not an exact science, it's better safe than sorry.

You would have most likely been fine considerring it's been almost 24 hours but people have gotten DCS for driving up a mountain In a car. Can't really know.

 

[Brett Hatch]

Views differ in this area a lot. For rec dive profiles PADI recommends a 12-hour no-fly window for a single dive day, or 18 hours if you did multiple dives, and either way ideally shooting for 24 hours. DAN recommends a minimum of 12 hours for single dive, 18 hours for multiple dives a day and/or multiple dive days in a row. US Air Force 24 hours, US Navy just 2 hours

I don't know enough about the science and medicine to say whether the variables you mentioned -- low altitude and short duration -- are helpful or even meaningful. Maybe @Duke Dive Medicine or @Dr Simon Mitchell could chime in here. Best of luck, I do hope that you find some reasonable basis to make a safe decision in cases like this

Edit to add: link to DAN article on flying after diving. Also, you may want to take a look at a chart of pressure as a function of altitude. In particular, the change in pressure from sea level (14.7 psi) to 10,000 feet (10.1) psi is actually larger than the difference in pressure of the high-flying planes, since they pressurize the cabin to around 11-12 psi (source: the DAN article above)

I think you should approach this very cautiously, and seek advice from a professional if at all possible. Maybe calling the DAN diving medicine hotline would be a good idea? If you are in the US, that would be +1 (919) 684-2948, and then press 4.

 

[scubadada]

Commercial planes are pressurized to 6-8000 feet, 12-11 psi. DAN guidelines for flying after diving are 12 hours for a single, no-deco dive and 18 hours for multiday or repetitive no-deco dives. You would have had 21 hours. I can't comment on the 10,000 feet, someone else can, perhaps you could have flown a little lower? Seems like flying may have been OK, I have occasionally flown after days of diving after a little over 18 hours. Longer is more conservative.

Edit: I see that @Brett Hatch posted while I was typing

 

[ATJ]

According to this: Adjusting Cabin Pressure Eases Air Passenger Discomfort.

Most commercial aircraft are pressurized to 6,000 to 8,000 feet, not sea level.

so your flight in a light plane would be far worse than in a commercial plane.

 

[tursiops]

I ended my dive in which I dove to 110ft at 11am yesterday

The US Navy Diving manual gives procedures for this. it is based on the highest Pressure Group you had in the 24h prior to the flight. You say you dived to 110 ft, but did not say how long. If that was a dive to the NDL limit, you'd be in PG H (Table 9-7). According to Table 9-6, an H diver ascending to 10,000 feet needs to wait 19h18m before flying. You would have had 21h. So, according to Navy procedures, you'd have been OK. Use at your own risk!

 

[broncobowsher]

As mentioned, not an exact science. Generally guidelines are based on worst case scenarios.
Times like this are where I learned to love my Shearwater, look at the tissue loading graph. Learn how it works. Do a dive, do multiple dives, do multiple days of diving and see how the slow and fist tissues respond.
While nothing is a guarantee, I am much more comfortable now that I know what is going on. I'll drive over a mountain pass after doing a planned deco dive the same day. Not straight out of the water, not coming out of multiple days of hard diving, and it is a gradual climb much like a gradual ascent in the water.

I would have taken the flight. Not sure exactly what your 110' profile really looked like. But guessing a fairly standard recreational profile and the amount of time.

 

[Duke Dive Medicine]

The US Navy Diving manual gives procedures for this. it is based on the highest Pressure Group you had in the 24h prior to the flight. You say you dived to 110 ft, but did not say how long. If that was a dive to the NDL limit, you'd be in PG H (Table 9-7). According to Table 9-6, an H diver ascending to 10,000 feet needs to wait 19h18m before flying. You would have had 21h. So, according to Navy procedures, you'd have been OK. Use at your own risk!

@Brett Hatch , thanks for the add. @Karriff karim , I don't have much to add to @tursiops ' post above.

Best regards,
DDM

 

[boulderjohn]

I wrote an ascent to altitude article that may help. It fully agrees with they key posts in this thread, but it has a little bit of extra that may be helpful, especially in regard to the US Navy document referenced by Tursiops. The problem with that is the table pressure groups are US Navy pressure groups, so you have to use the Navy tables. Most people do not have them and have no way to guess where their diving falls. My article has a handful of examples of common dive times and depths and tells what their pressure groups would be.

 

[tursiops]

The problem with that is the table pressure groups are US Navy pressure groups, so you have to use the Navy tables. Most people do not have them and have no way to guess where their diving falls.

Yeah, that is why I referenced the US Navy Dive Manual. The only two tables needed to play the table game for non-NDL flying-after-diving according to USN procedures are these two, Table 9-7 to give you your PG, and table 9-6 to give your wait time before flying.