Getting bent on Haleakala

[H2ODoc]

We were planning on biking up Haleakala (10,000') on our upcoming trip and until just yesterday, I didn't even think about the risk of riding up there after diving. :shocked2:

I wonder how many people don't think of that, and drive or ride up there with too short of an SI. Any stories?

I think we are going to get the ride in before we do any diving, just to be safe.

 

[pjhansman]

They don't recommend diving and Haleakala on the same day.

No worries.....most of the diving is finished early in Maui anyway, so take the afternoon off and do the bike trip the next morning and catch the sunrise.

 

[MauiScubaSteve]

If you dive with a local operator, every release of liability I have seen on Maui includes a warning to not drive above 2000' until at least 12 hours after a dive.

If you just rent tanks and weights and dive on your own I do not know if there is a release warning you to wait to do Haleakala;

If you do more than one shore dive in a day, especially including Airport Beach (Kahikilli Beach), which can be nearly 100' deep, then you should be waiting at least 18 hours.

Yes, there have been cases of DCS from driving up Haleakala after diving. I complained to nearly every PADI administrator when Sport Diver magazine included a side box to a Maui adver-article that listed Maui highlights something like this;

"You must dive Molokini crater and then you must visit Haleakala crater."

If you have been paying attention you will have noticed that Sport Diver has no "Letters" section; perhaps because the only letters they receive are valid complaints.

 

[acooper]

A problem in my life, but one I do think about. I work a couple days a week at 13,600ft. Weekend dive? Going to the summit on Monday? None of the standard references I have found address this extreme. How long does it take to flush the N? Is 24hrs enough? I have done a dive on Sunday morning and gone to the summit on Monday without problem, but it is generally something I avoid doing.

 

[Damselfish]

Exercise after diving is another thing often recommended to be careful about, so that is another consideration - especially if you're biking UP Haleakala!

 

[H2ODoc]

..... if you're biking UP Haleakala!

Good point.

Yes - we like to earn our downhills!

 

[LeadTurn_SD]

A problem in my life, but one I do think about. I work a couple days a week at 13,600ft. Weekend dive? Going to the summit on Monday? None of the standard references I have found address this extreme. How long does it take to flush the N? Is 24hrs enough? I have done a dive on Sunday morning and gone to the summit on Monday without problem, but it is generally something I avoid doing.

Sort of off topic: Table 9-6 in the USN Dive Manual is what I've used as a reference, but it only goes to 10,000 feet.

I believe local operators will routinely urge a 12 hour interval before driving home to Hilo after a single dive in Kona (or vice versa) due to the altitude change while driving through Waimea or Volcano (and will recommend NOT driving over Saddle Road).

While this is certainly conservative and very prudent advice, many divers for many years (me included) have used considerably shorter surface intervals, depending on the dive profiles, in line with the recommendations in Table 9-6.

But, there is a huge difference between the highway elevations in Waimea and Volcano and the observatories on Mauna Kea, and for "typical" Repetitive Group Designators you might have after a single dive (G or H), the minimum might actually exceed 24 hours.

I'm just guessing/estimating, based on the values for G and H groups, for 10,000 feet, which are 17:27 and 19:18 respectively. The SIT jumps considerably for each 1,000 feet of altitude, and does not appear to be linear.

Back on topic: So, be careful about driving to Maune Kea or Haleakala after diving, even after an overnight surface interval.

For visitors, I'd recommend the visit to Haleakala or Mauna Kea at the beginning of their vacation, then diving afterwards.

Best wishes.

 

[muddiver]

One way to reduce the surface interval need before going to work at altitude would be to dive every dive on Nitrox. If the dive is deep enough (and if ANDI certified or advanced Nitrox certified) you could ascend from the last dive on a rich mix to accellerate decompression.

Also please note that the U.S. Navy Table 9-6 is based on the U.S. Navy diving tables. Therfore you should follow the Navy table to plan your dive if you want to use the ascent to altitude table 9-6.

This might be a good question for the NEDU forum to see how the table was intended to be used and what it's limitations are.

 

[H2ODoc]

We will either do Haleakala the first morning of the trip or at the very least, we'll only do one dive the morning before (24 hours +/-), and like Lead_TurnSD said - use Nitrox. I'll lookup the tables to see what group we'd be in on nitrox vs. air.

I guess one of my points was the casual (clueless?) diver who may not even think of the altitude factor. We have the Blue Hole down in New Mexico where people dive, then drive up and over Raton Pass at 7800' and I've heard of a few cases of DCS happening as a result.

 

[boulderjohn]

I guess one of my points was the casual (clueless?) diver who may not even think of the altitude factor. We have the Blue Hole down in New Mexico where people dive, then drive up and over Raton Pass at 7800' and I've heard of a few cases of DCS happening as a result.

Of course, since the Blue Hole is a little over 4,600 feet, you are really only looking at a little more than a 3,000 foot elevation gain to Raton Pass, and it takes about 3 hours of driving to get there. You real concern is well before that--you have nearly a 2,000 gain before you reach Las Vegas.

But you are right, people have been diving in Santa Rosa, NM, driven back to Colorado and gotten bent after the trip. I know one very well--he did the same profiles I did for three days. I felt great. He was bent--seriously.