Diving after flying

[Lost Yooper]

There are quite a few divers who believe this subject is one of the biggest falacies of diving. If you get bent at 8000', then you were probably in pretty bad shape anyway.

Good post Dr. D.

Mike

BTW, I certainly misspoke on the 3000' pressurization (6-8K is correct).

Also, for those who deco out correctly, then all this become mute anyway.

 

[The Iceni]

Thanks again DD,

I think we are getting there at last!

I like to act as the devil's advocate and In the UK we are still advised as was malleycat " that you should wait for a certain period AFTER flying before you dive".

I had been trying to get my head around this for some time and had my rear end flamed on the BSAC forum for suggesting it was load of old poppycock.

To summrise, then.

It would seem that the reduction of pressure due to flying, by itself, is not thought to prohibit diving without a break as long as the diver is fit, rested, hydrated and otherwise medically fit to dive.

This is just as well, as to my mind one of the best wreck diving sites in the UK is at Scapa Flow - off the northern tip of Scotland- the site of the scuttled WW1 german high seas fleet. This is most easily reached by airline so there wouldn't be much diving on a long weekend trip there if a whole day (12 hrs) was lost after the flight there as well as on the way back.

thanks again.

 

[Lost Yooper]

I get flamed, harassed, and picked on for all kind of things regarding unconventional scuba related stuff.

Take care.

Mike

 

[joewr]

Originally posted by roakey

Mike,

I flew with a guy that had an altimeter on his watch and set it correctly before takeoff. We saw 6-8k feet throughout the flight, except near the end where they slowly pressurized the cabin to ambient so the descent wouldn't be hard on folks.

Roak

I used to be a private pilot. The "magic number" was 10,000 ft: at that altitude and higher you either had to use an oxygen mask or be in an airplane with a pressurized cabin to avoid hypoxia, lack of O2 to the cells. The effects are a little like nitrogen narcosis, something a pilot would like to avoid!

Commercial jets, as I remember, shoot for the pressure at about 8,000 ft when they exceed that altitude. They could pressurize to 1 atm, but that is costly with little or no benefit.

Also, they repressurize on ascent mainly to be able to open the cabin door when they "dock". It is somewhat difficult to open the door when there is "partial vacuum" in the cabin.


Joewr...

 

[joewr]

Originally posted by Lost Yooper
I get flamed, harassed, and picked on for all kind of things regarding unconventional scuba related stuff.

Take care.

Mike

And, that must be why you are called, "Lost"! When you are "Found", you will only be harassed and picked on. Flaming will be reserved for those times when you stray...

Joewr...lost in space, time and energy...

 

[Liquid]

Originally posted by Lost Yooper
I get flamed, harassed, and picked on for all kind of things regarding unconventional scuba related stuff.

It's only becouse we love you

 

[Lost Yooper]

You guys crack me up!

 

[Dr Deco]

Dear Readers:

I am not aware of any laboratory data on diving following a flight. I do know this, however, that even when test subjects have a great number of Doppler detectable gas bubbles while at altitude, these are gone upon repress to sea level. This loss usually occurs during the repress it self and the longest I have noted them is about ten minutes. This would indicate to me that microbubbles are not present following repressurization to sea level. This is with a depress that produces many vascular bubbles in the test subject (say, a press to 25,000 feet). A small ascent to 8,000 feet should be trivial.

The only way that I could see a problem develop is if, following descent, microbubbles normally present in tissue are not “semi-microbubbles.” These are more easily enlarged with physical activity to form the micronuclei that can grow following the dive.

Thus, I would be skeptical (on little evidence, though)of an increased risk of DCS following a flight, although, I could possibly see how it could be problematic with vigorous post-flight/pre-dive activity.

One should, however, always be aware of musculoskeletal activity and diving, remembering that gas loading is only one half of the equation (micronuclei are the other half).

Dr Deco

 

[JRRKAR]

Thanks for the info. That gives me a little more to go on. I'm not sure how our Sunnto computers would handle it. I'll have to look into that.

Is there any guidlines to "Diving after flying"? A friend said he thought you had to wait 24 hours after flying to dive. I didn't think it mattered?

As per Belize goes...since you made this flight. If you were going to spend an extra couple of days diving and/or sightseeiing....would you stay in San Pedro or Placencia?

 

[DocVikingo]

Some very conservative dive medicine experts recommend a 24 hour break between landing & diving.

Personally, given that it's reasonable I often dive as soon as possible after arrival. For me, this means I just flew to Cozumel, not to Fiji.

You should endeavor to drink as much as possible to counteract the drying effects of air at altitude, and to avoid alcoholic & caffeinated beverages. Also, get as much rest as you can.

If you arrive alert, well rested, well hydrated, feeling fine & in good spirits, diving shortly after flying likely adds no significant additional concerns. If you're jetlagged, dehydrated, fatigued, feeling lousy & irritable, then it might be wise to save the scuba for the next day when you're recovered.

BTW, N2 level from flying is not an issue.

This is educational only and does not constitute or imply a doctor-patient relationship. It is not medical advice to you or any other individual, and should not be construed as such.

DocVikingo