hot tub and diving?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

hbhobby

Contributor
Messages
127
Reaction score
4
Location
GLobe Arizona
I learned in several classes that hot tubbing after diving isn't a good idea. It makes sense that heating something would make the gas move out of solution easier. Over christmas vacation I went to "the crater" in Utah and dove in a hot spring that was 95 degrees at depth, what, if any, relationship is there between heat/cold and nitrogen loading? Would there be a problem hot tubbing after a dive like that since the water I dove in was "hot" itself? Do I need to be more conservative when diving "hot" water vs cold water? When diving cold water am I better off staying cool foir my surface interval? Sorry for so many questions but I never thought about it untill I looked at my temp gauge at 50 feet and it read 94 degrees.:confused:
 
that's a mighty toasty dive! did you make some tea while you were down there? just kidding...

probably a good question for DAN if you haven't asked already...

erik
 
Hi hbhobby:

Experience seems to indicate that diving warm [e.g. a dry suit] and offgassing cold [e.g. doffing your gear on the boat in winter] can result in DCS. The guess is that this effect results from inappropriate dissolved nitrogen exchange.
 
If you call DAN, please post the result here. I have always been curious about that scenario. I do a lot of cold-water diving (4c - 6c water temp) and I wonder about the effects of the warm car-ride home. I would suspect that any-time you are in an environment hotter than your core body temp (37 degrees C) you are going to be expanding that gas more than its natural state in your body, which is a bad thing.
 
Hi hbhobby:

Experience seems to indicate that diving warm [e.g. a dry suit] and offgassing cold [e.g. doffing your gear on the boat in winter] can result in DCS. The guess is that this effect results from inappropriate dissolved nitrogen exchange.

Which is to suggest (I guess) that changing conditions during offgassing is a problem regardless of the direction of change.

You would think that diving cold and then jumping in a hot tube would be the problem since it would indicate slower ongassing and more rapid offgassing.

If diving warm with colder surface conditions is also a problem due to "inappropriate" dissolved nitrogen exchange then most any condition after a dive that is different than the dive conditions is potentially a problem.

Is this a correct interpretation of your understanding? It makes sense but I just want to make sure I'm understanding what you're saying.

It would also lead to the conclusion that the scenario in the original post is not a problem...going from a warm dive to a warm hot tub after the dive.
 
If you call DAN, please post the result here. I have always been curious about that scenario.

Hi Rutger,

DAN's take on post-dive hot tubbing can be found here:

Diving Medicine FAQs
Hot Tubs after diving
http://www.diversalertnetwork.org/medical/faq/faq.aspx?faqid=209

As you are a cold water diver, you might also find the following to be of interest:

Cold Stress Complicates Decompression Risk
http://www.diversalertnetwork.org/medical/faq/download/Cold Stress Complicates Deco GUE Art.pdf

Interestingly, pre-dive exposure to high temperature may have a protective effect against DCS. Here is my Jul '09 Undercurrent (http://www.undercurrent.org) piece on a recent study of the matter:

"Can Saunas Prevent Decompression Sickness?

By adhering to conservative profiles like slow ascents, extended safety stops and appropriate surface intervals, the healthy, fit diver faces only minuscule risk of decompression sickness (DCS). Still, much has yet to be proven about the exact causes of DCS. According to a recent study, a long sit in a hot sauna may help to prevent it.

In their article published in the journal Aviation, Space and Environmental Medicine, researchers from France had 16 military divers take a 30-minute dry sauna heated to 49 degrees Fahrenheit. An hour later, the divers took a simulated dive to 98 feet in a hyperbaric chamber. Then, everyone did the same dive without sitting in the sauna beforehand. Post dive Doppler readings found that circulating bubbles were reduced by about a third in divers who had done the sauna/dive procedure. They also had significant reductions in systolic blood and pulse pressures.

Researchers opine that the decrease in inert gas bubbling may in turn decrease the risk of DCS. Possible reasons include changes in plasma heat shock protein and nitric oxide levels, and sweat dehydration. However, the findings can only be considered suggestive for the time being.

Even if these findings are replicable, various temperature levels will need to be tried to see if lower temperatures can produce similar results. There’s really no safe, workable way to subject the body to temperatures in the 150-degree range other than by dry sauna (wet environments at that level could cause burns). If the reported reduction in gas bubbling in fact does require temperatures at or near this extreme, you’d be out of luck if you don’t have access to a sauna heated to this temperature range.

As a final caution, it’s important not to confuse pre-dive with post-dive sauna, or even with post-dive hot tub, shower or other methods exposing the body to high temperatures. Excessive heat after a dive can accelerate inert gas elimination and increase bubble formation, and so should be avoided. Besides deep stops and slow ascents, spending your first hour of post-dive time in a warm, but not hot (or chilling) setting, is another way to keep DCS at bay. - - Doc Vikingo

“Predive Sauna and Venous Gas Bubbles Upon Decompression from 400 kPa,” by Jean-Eric Blatteau, M.D. et al.; Aviation, Space and Environmental Medicine, December 2008."

Regards,

DocVikingo
 
I have been diving wet here in South Carolina recently. It has been a little chilly (52*F). I have been running deco dives to 135- 175' for 20min. resulting in 49-69min run times. If I am cold during the dive and warmer as I surface, I would assume that I would on gas slower and off gas faster. I have not had a hit, thank God, but I am curious if I should extend my deco stops at 20' and 10' to prevent DCS. Dr. Deco, what is your take?
 
Which is to suggest (I guess) that changing conditions during offgassing is a problem regardless of the direction of change.

No, I dont think that follows. I think there is evidence that being "colder" on the bottom and "warmer" (i.e. enabling a suit heater, or having a thermocline shallow) is "better" (in the case of mandatory deco dives anyway)

Being warm on the bottom and cold on deco I think is demonstrated to increase the risk of DCS in "tech" dives
 
Which is to suggest (I guess) that changing conditions during offgassing is a problem regardless of the direction of change.....It would also lead to the conclusion that the scenario in the original post is not a problem...going from a warm dive to a warm hot tub after the dive.

Hi gcbryan,

Hi Nick,

The solubility of gases is inversely related to temperature. As such (provided that extremes of both ends the temp range are not involved), from a DCS standpoint it is preferable to be cooler at the bottom and warmer at the surface than vice-versa.

But this does not mean that going from a warm dive to a warm hot tub immediately post-dive is without increased risk, particularly when inert gas loading is substantial.

Regards,

DocVikingo
 
Diving cooler than you off gas is always the way to bet.
 

Back
Top Bottom