Driving Over Mountains After The Last Dive Of The Day

[archiebald]

I live in the mountains of Japan at 700m altitude (2,300ft) and when driving to and from the Izu peninsula, the road briefly climbs to 1,000m (3,300ft).

From my home, I can drive down there in the morning, possibly do 2-3 dives and return home on the same day. Based on the distances, after finishing the last dive, I would likely start climbing the mountains about 2-3 hours after the end of the last dive, takng about 20 minutes to get over the peak.

So here are my questions....

1. Is this altitude change high enough to cause me any problems if I dive to normal computer limits?
2. If I preset my computer to a more conservative setting, or maybe to an altitude setting above sea level, would this likely be enough to prevent any issues?

I haven't tried this yet, just thinking of how to get some additional diving in other than the annual family vacation.

 

[boulderjohn]

Most organizations that have set rules related to increasing altitude/flying after diving have said that an increase of 2,000 feet is acceptable without a wait. You should not have a problem.

 

[Doug - aka "Dogfish"]

I've heard the story, (I think it was here) that a dive instructor in the caribbean once had a diver sitting in the boat ask, "what is the altitude here?" pretty funny.......

 

[TSandM]

I have pretty much the same situation. I drive over a mountain pass of about 3500 feet to go to work. A friend who lives on the other side of that pass had contacted DAN, who had told him that it wasn't a problem. If you think about it, if it takes you an hour to get out of your gear and pack it, and 2 to 3 hours to make it to the top of the pass, your ascent rate is pretty darned slow . . .

 

[Doug - aka "Dogfish"]

We dive at Catalina island all weekend and then head home via the Tejon pass, I-5. I think that is 4100 feet. Is that a problem?

 

[archiebald]

Thanks for the responses so far, seems that I have nothing to worry about.

 

[boulderjohn]

We dive at Catalina island all weekend and then head home via the Tejon pass, I-5. I think that is 4100 feet. Is that a problem?

According to the NOAA tables, it all depends upon how much diving you did. Note that the pressure groups in that table are U.S. Navy, which are different from most other agency tables. Still, it should give you a pretty good idea. You should probably not set out for a few hours after your last dive, which is probably happening anyway.

To be honest, there is not really good experimental knowledge here, and there are individual factors in play for each drive to altitude, such as how quickly does your drive get you to your maximum ascent or do you do a series of short climbs with intervals at that same altitude in between (decompression stops).

Divers in the Denver area frequently do dives at a site at 4,600 feet in New Mexico. Going home, we do a fairly rapid ascent of nearly 1,500 feet, followed by a long drive with little change in altitude, followed by a climb over a mountain pass at just over 7,000 feet. That really shouldn't be a big problem, and different people approach that ride with different degrees of caution. One weekend my buddy and I did three days of fairly aggressive diving, with one decompression dive on the last morning there. A snowstorm was coming, so we packed hurriedly and set out. To be safe, we breathed through our regulators on our oxygen tanks until we emptied them, about the time we crossed the pass. It was several more hours until we got back to Boulder, where I went to my home in town and he went up into the mountains to his home at about 8,000 feet. The next day I felt great, better than usual after a long diving weekend, but he was in the chamber. Other than the differences in our own bodies, the only difference in our three days was his ascent to his home in the mountains. Now, that is just one anecdote and it proves nothing, but I am still a bit cautious about this sort of thing, partially as a result of that incident.

 

[dpaustex]

I have to agree with the posters that say "caution". As noted in the NOAA tables, there are some guidelines.

However, you didn't say how deep, how long, how many dives in a series, etc. As pointed out, there are physiological factors that also come into play, that are not addressed by any method. The tables are a guide, only, as are the algorithms programmed into computers. Does it mean you'll never get a DCS hit if you use the tables or computer? No.

As pointed out, a very slow ascent (over the mountains) probably is not an issue, so you PROBABLY are fine, if you have no underlying issues (there are physiological issues that can be a problem).

Certainly be aware of the symptoms of DCS, and do not ignore them if they manifest themselves.

Otherwise, enjoy your diving (I am jealous you have close ocean, btw).

 

[miked]

I've heard the story, (I think it was here) that a dive instructor in the caribbean once had a diver sitting in the boat ask, "what is the altitude here?" pretty funny.......

I was asked that question, and I did post the story on SB. The lady who asked was trying to program the info into her dive computer.
Just for clarification, I'm not an instructor, and it happened (to me) in Bermuda. Could this question have been asked more that once ??

 

[adutto]

From my experience:
A - I normally dive at 900 mts
B - I live at 440 mts
C - In the middle there is a hill that reaches 1100 mts

I've been going from B to A to B (thru C) since I begun diving and never had an issue (that I know of )

This is in Cordoba (Argentina) by-the-way.