No Fly Time Calculation No computer

[JodiBB]

My computer also has a 24-hour default for No-fly time.

 

[bperrybap]

Quite right, early morning mental glitch. I was thinking 8000 and typed 3000 and on the small screen laptop I was using the 3 and the 8 are very similar so I didn't spot it. On the 17" monitor I'm using now it's quite obvious.

I wondered if that might be the case. I have over 40 eyes
as well. I feel for you....

--- bill

 

[Andy_W]

Well thanks guys, I think I'll be on the safe side this time 24 hrs min.

I was thinking to push it a bit further and squeeze for more dive.

 

[Web Monkey]

Hi guys, I need some help from you.
How to calculate No fly time if you don't have any computer? Let say for multiple recreational dive.
or should i limit it to 3 dives a day for 3 days dive = total 9 dives

thank you in advance

DAN recommends 24 hours if you've been doing multiple days of repetitive dives, or deco dives, and 18-24 hours if you've only done a few non-deco dives.

Terry

 

[cummings66]

I'll be a bit different from the other posters, I'll show you how I calculate the proper amount of time from diving to flying without using a computer.

First, I'll give you the proper formula.

It's 6x where x is normally 4.

So to solve it, 6x4=24 hours. There you go, math forumula to solve the mystery and how the computers do it.

The shortest interval I've seen is 18 hours for just a simple dive. On my computer if I go to 5 feet and up I'll get a 24 hour period.

I know this because my last dive was one to answer a question a fellow diver asked about why drysuit training is good to have. I dropped down to 7 feet, added air to the suit while he watched what happened and then I hung upside down for a few seconds with the fins on the surface and then righted myself. Took less than a minute, yet the computer counted that as a dive and my 24 hour period started after that short demo.

 

[halocline]

DAN recommends 24 hours if you've been doing multiple days of repetitive dives, or deco dives, and 18-24 hours if you've only done a few non-deco dives.

Terry

I thought the DAN recommendation was 18 hrs for multiple NDL dives, and "substantially longer" for deco dives. Where does it say 24 hrs?

 

[DandyDon]

DAN recommends 24 hours if you've been doing multiple days of repetitive dives, or deco dives, and 18-24 hours if you've only done a few non-deco dives.

Terry

You might review what DAN actually says. It changed a few years ago.

Most of the posters here seem to think they know more than DAN, tho? The DAN guidelines are really rather conservative. Read their Accident reports for the last few years - see if you find any hits while flying 18 hours after diving. Check our A&I forum. Check the ScubaDoc site. Find me a reason to skip that dive.

If a good dive is availble in the 18-24 hour range, I'm in. I will use Nitrox if available, but if not, I'm still in. Now if you're much older than me, you might want to be more conservative. I'm only 58-11/12.

 

[Floridawannabe]

I vote 24 hours. Also my computer has a 24 hour count down. Better safer than sorry.

 

[DandyDon]

Guess I'm gonna have to agree with GUE again about the dumbing down of divers because of computers.

I guess so. There is no reason for that 24 hour countdown timer to still be on computers, but it is - and most of those posting here are going by it, regardless of the facts.

 

[gcbryan]

Correct me if I'm wrong but I believe the logic for the time to fly is based on clearing the slowest tissue compartment likely to be at issue in recreation diving. Since most dives last no more than 60 minutes and almost all are within 120 minutes the 120 minute compartment is controlling. I believe it is generally accepted that 6 times the half life means that you are as clean as you are going to get. Therefore 6 times 120 minutes (2 hours) is 12 hours. You should be cleared of excess nitrogen after 12 hours. Depending on how many dives over how many days I suppose that it is more conservative to wait 18 hours but in any event I think this is the logic behind how long to wait before flying.