What altitude to stay after diving?

[billt4sf]

We will be traveling again to the Big Island for diving in late 2013. We always have this question about how high up is it good to stay at after a dive? Given the topography of the island, I'm sure this question has come up before, I searched but did not find anything. (I am new to ScubaBoard, I'm not sure if I searched correctly.)

I asked DAN and I copied the response below. Basically they said that there is no guideline for night stays but "be conservative". We have a B&B booked for 1500' but I am thinking that we should find a place closer to sea level as we will be diving most days. We are novice divers, we dive to maybe 50 - 60' or so, rarely more and we try to make our safety stops but we do not have the need to make decompression stops.

Thanks for any thoughts.

- Bill



Thank you for contacting DAN Medical Services. The following guidelines are the consensus of attendees at the 2002 Flying After Diving Workshop. They apply to air dives followed by flights at cabin altitudes of 2,000 to 8,000 feet (610 to 2,438 meters) for divers who do not have symptoms of decompression sickness (DCS). The recommended preflight surface intervals do not guarantee avoidance of DCS. Longer surface intervals will reduce DCS risk further. For a single no-decompression dive, a minimum preflight surface interval of 12 hours is suggested. For multiple dives per day or multiple days of diving, a minimum preflight surface interval of 18 hours is suggested. For dives requiring decompression stops, there is little evidence on which to base a recommendation and a preflight surface interval substantially longer than 18 hours appears prudent.
This is the data for altitudes of 2,000 to 8,000 feet. There is no data for altitudes under 2,000 feet, so I can not tell you it is safe or not. I can only recommend that you be conservative with your decision. Feel free to contact DAN with any additional questions.

 

[knotical]

A couple of recent threads:

http://www.scubaboard.com/forums/hawaii/428357-upcoming-trip-hawaii.html

http://www.scubaboard.com/forums/hawaii/412609-altitude-issues-if-staying-captain-cook-area.html

In general, since you’re only going to 1500 feet, you’re probably OK. Especially if you don’t rush to your B&B.
You’ll be off-gassing immediately you leave the water, and will continue as you disassemble your kit, pack, etc.

 

[DiveMaven]

If you plan on diving in the morning, simply have lunch after diving and before heading to your B&B. Although 1500 feet shouldn't be a problem, if it were me, I'd want a good hour or more after my last dive.

 

[GrumpyOldGuy]

At <2000' it's not an issue, it's not considered an altitude dive and there should be no additional precautions needed.

 

[Damselfish]

is your B&B at the highest altitude of the drive or do you have to pass through anyplace higher on the way there?

 

[billt4sf]

The B&B is at or near the highest elevation of the drive.

Frankly I am surprised at everyone's answers so far. According to DAN, flying above 2,000 ft is not recommended until 12 - 18 hours after diving. Yet everyone thinks 1,500 ft is OK an hour or so after diving? That doesn't seem "conservative" to me.

I agree that the chance of DCS are probably low. But the results can be catastrophic. One does not have to troll very far on ScubaBoard to find someone that followed the guidelines and got DCS sick. In my situation there ARE no DAN guidelines. Perhaps I am answering my own question, but I did want to see what others say.

- Bill

 

[GrumpyOldGuy]

The B&B is at or near the highest elevation of the drive.

Frankly I am surprised at everyone's answers so far. According to DAN, flying above 2,000 ft is not recommended until 12 - 18 hours after diving. Yet everyone thinks 1,500 ft is OK an hour or so after diving? That doesn't seem "conservative" to me.

I agree that the chance of DCS are probably low. But the results can be catastrophic. One does not have to troll very far on ScubaBoard to find someone that followed the guidelines and got DCS sick. In my situation there ARE no DAN guidelines. Perhaps I am answering my own question, but I did want to see what others say.

- Bill

Bill,

The DAN recommendation is a blanket, don't fly for 12-18 hours. Without crunching the numbers, its the best they can do and a good all round number. Most flying is done ay 8000' equivalent altitude in pressurized cabins. The 2000' is at the very floor, you are below that. I don't think most dive computers that have altitude sensors would trigger on it either (I know mine does not).

If you care to crunch the numbers, NOAA published an "Ascent to Altitude Table" that does go down to 1000ft, I provided a link. You have to use their tables as its not directly compatible to PADI tables in terms of letter groups, but it will give you a good idea of where you are if you run some dives on their tables to see what a planned dive would do.

http://www.ndc.noaa.gov/pdfs/AscentToAltitudeTable.pdf

In the end its your call, nothing wrong with eating lunch seaside before you return to the B&B

 

[farsidefan1]

I do training dives at the crater (5,700 feet) and go over a pass at 8,000 feet. I have lunch before I come home (5,000 feet). Just read up on altitude diving and give yourself some time before ascent. Of course the maximum depth at the crater is 63 feet.

 

[chrpai]

We have a B&B booked for 1500' but I am thinking that we should find a place closer to sea level as we will be diving most days.

I think that's the key right there. You are going to be doing multiple days of diving traveling from sea level to 1500'. You can probably get away with this one and you can probably get away with this more then once.... but I'd change hotels so that it's not part of the dive plan.

 

[billt4sf]

If you care to crunch the numbers, NOAA published an "Ascent to Altitude Table" that does go down to 1000ft, I provided a link.
http://www.ndc.noaa.gov/pdfs/AscentToAltitudeTable.pdf

Thanks, this is really helpful.

- Bill