Driving to 4000Ft after diving. Need recommendation ASAP.

[divebrasil]

Hi and thanks for reading this.

I was planning to do 3 dives in one day and drive to the Big Island Volcano National Park at 4000ft the next day. I am wondering if it's safe?

The drives profile will most likely be:
50ft - 50minutes - 9am
65ft - 35min - 5pm
40ft - 50min - 7pm

THe volcano park is at 4000 ft, but the drive there is more on the 2500ft range and then goes to 4000 in the end.

I was planning to drive the up to 4000ft around noon. It would be like 16h interval until noon.

What do you think?

THank you so much!

 

[Kstnbike]

You should* be perfectly fine making that ascent to altitude after a 16 hour surface interval. NOAA Ascent to altitude tables have you clear at less than 14 hours and that is following a square dive profile. The tables can be found here for reference.

http://scuba-doc.com/USNTab9.5.html

-Kstnbike



*I put "should" instead of "will" because people all react differently. Sure it's probably a 1 in a million chance you'd get bent but, I've heard of people making dives well within the NDL's (following proper procedures) and still getting bent.

 

[knotical]

I see you are a PADI diver, so a caveat:
The pressure groups in the table Kstnbike refers to are not PADI’s, they are NOAA’s.
You can find the NOAA equivalent of PADIs’ RDP here:
http://www.ndc.noaa.gov/pdfs/NoDecoAirTable.pdf
If you work your dives through that table, you should still find that you’re OK.

 

[jviehe]

Hi and thanks for reading this.

I was planning to do 3 dives in one day and drive to the Big Island Volcano National Park at 4000ft the next day. I am wondering if it's safe?

The drives profile will most likely be:
50ft - 50minutes - 9am
65ft - 35min - 5pm
40ft - 50min - 7pm

THe volcano park is at 4000 ft, but the drive there is more on the 2500ft range and then goes to 4000 in the end.

I was planning to drive the up to 4000ft around noon. It would be like 16h interval until noon.

What do you think?

THank you so much!

Follow your PADI RDP and wait 18 hours, would be my personal reccomendation. The idea is to dive conservatively.

 

[Spade]

18+ IMO.

Tissue Half-time, Nitrogen (mins) Half-time, Helium (mins)
Spinal Cord, 12.5, 12.5
Skin, Muscle, 37 - 79, 14 - 30
Inner Ear, 146 - 238, 55 - 90
Joints, Bones, 304 - 635, 115 - 240

As far as half-times go, it's 6 to completely off-gas
0 half time = 100%
1 half time = 50%
2 half time = 75%
3 half time = 87.5%
4 half time = 93.75%
5 half time = 96.875%
6 half times = a general acception that you're 100% even though realistically it's 98.4375%

Either way, with a multiple dive profile, I'd stay out 24 hours.

 

[Gene_Hobbs]

http://scuba-doc.com/USNTab9.5.html

There are notes associated with this table. You can find them in the USN Manual with table 9-5.

I have a fuzzy copy I keep on a page for myself here.

 

[divebrasil]

Thanks all. I am having a hard time using the NOAA dive table for multiple dives. Do you know in what letter group I fall after that last dive?
Thanks

 

[AzAtty]

I typically use the RDP, so I may be doing the NOAA table wrong, but here are my results:

After your eight hour surface interval between the morning and evening dives, you're in pressure group "A" with 4 minutes of RNT to account for on the first evening dive. After your last dive of the day, I put you in group "I". Pressure group "I" is also the highest pressure group experienced throughout the series. The SI required by the Navy table for an "I" diver before ascending to 4,000 feet is just over five hours.

DAN's guideline for an ascent to 8,000 feet after a profile such as yours is 18 hours. IMO, your profile is pretty benign. If you have a nitrox card, I might suggest diving the last two dives on 36% (dive as air), which would drop a couple of pressure groups and would cut your minimum SI on the Navy table to under an hour and a half.

PLEASE DO YOUR OWN VERIFICATION ON THE RDP BECAUSE YOU MAY DIE HORRIBLY IF YOU RELY ON MY CALCULATIONS!

 

[altitudemike]

Do it. You'll be fine.

 

[Al Mialkovsky]

So are you in a pressurized car while driving up there? I wouldn't do it. It's 18 hours after diving for a pressurized airplane, 24 hours for a non pressurized plane. The only way I would do such a thing is if my dive computer said I was good to go.

Nice vacation, why follow dangerous advice and take a chance of wrecking it. Either postpone the drive or take some dives off.

The surface interval people are responding to is the noon one, you are well above 1000 feet long before noon.

But do what you will, we're all adults. I'd do the dives and forget the drive myself.