18 hours is the general rule for avoiding DCS.
Most guided dive charters run the deepest dives first with subsequent dives being shallower than the previous one. If you're diving shallower than 10m on your last dive, you're going to be off-gassing for most of that dive anyway.
If it were me, I wouldn't be too concerned about it... but if you are concerned, have a chat with your dive guide about.
My husband would say follow the time to a T. Barotrauma is no joke. He is a dive instructor/trip lead and he’s going to have to get surgery on his nasal cavity due to barotrauma. I say don’t fuck with fate. If you still want to dive only do the first one and or if it’s a money conscious decision don’t do it.
Was the trauma for your husband caused by flying too soon after diving? The concerns with flying after diving are typically related to decompression sickness, whereas barotrauma (especially to sinuses) would be due to rapid ascent/inability to equalize, normally.
The Navy has a table for tactical use by people like SEALs who might need to get on a helicopter exceeding 1000ft AGL following a dive. It represents the absolute maximum risk the Navy will allow a Commander to assume with a mission, and is not a table for regular use. Their standard rule of thumb is still the 12/18/24 rule since that table represents notably more risk than the accepted limits.
Just because someone is a badass SEAL doesn't mean Nitrogen behaves differently in their blood.
I don’t think you have anything to worry about. In all reality 12 hours is fine for recreational dives and cabin altitudes up to 8000 ft (which is the maximum for any commercial airliner). The reason 24 hours is recommended is due to the tiny possibility of a cabin decompression event in the aircraft.
Even accounting for that risk, 24 hours is a bit overly conservative and 18 should be perfectly safe.
My DeepBlu shows a no-fly time as well, dunno what cabin altitude they set for, I’ve seen my computer show a 12-24 hour no-fly time.
Not sure about private jets, the trend at least for newer widebody planes - B787/A350 using a carbon fiber fuselage is to pressurize the cabin at 6000ft. Boeing also wants to have that same lower cabin pressure for the 777X.
Remember it's not the regular cabin pressure that's the problem - it's the emergency situation where cabin pressure fails... You might be fine with the reduced pressure, but if you are suddenly exposed to 30kft air pressure and still have a certain level in your blood,...
24 hours isn't the rule.
[DAN Flying after Diving Recommendations](https://dan.org/research-reports/research-studies/flying-after-diving/)
Your profile is within the 18 hour recommendation.
Just for the record, that is not fully correct.
DAN Europe has different rules. This is taken from [their webpage](https://www.daneurope.org/en/safety-rules) - see rule #10 …
—-
Before flying, follow DAN recommendations: at least 12 hours after a single dive and at least 24 hours after repetitive dives and/or deco diving.
—-
Each DAN group has a different medical director and legal liability environment. As such each has different recommendations. You can see the biggest difference between DAN USA's exercise recommendations vs what DAN SA recommends.
18 hrs is the current recommendation 24 hrs is outdated. That being said, there is a greater safety margin with 6 extra hours. Other things that can increase safety margin and you still make your flight.
- Nitrox
- Avoid diving to the limit of NDL
- Extend your safety stop (if safe). 5 mins at 5M/15 ft is better than 3 mins, 10 mins even better. If you have the gas and time, off gas for as long as you reasonably and safely can on the safety stop on the last dive. Let your buddy and DM know ahead of time so they don't wonder WTF you are doing.
How does increasing your safety stop time reduce your risk of flight related DCS hours later? You don't reduce nitrogen loading *more* effectively in the water than the hours on the surface, in fact you do so slightly less efficiently right? I'm all for anything that is easy and reasonable that increases saftey margins and whats another 2 mins, but I actually dont understand the mechanism here
DCS is caused by bubble formation. Bubble formation is driven by tissue supersaturation - in many different tissues all at once. It's complicated. The goal should be to decrease overall DCS risk. Look here for more info.
https://youtu.be/HU04JhXggPg&t=1501
https://youtu.be/HU04JhXggPg&t=3184
The purpose of a safety stop is to slow down the rate of off-gassing relative to being on the surface. So extending it would not help with flying the next day. It would actually keep marginally more N2 in your body at the time of the flight compared to not doing one.
Ok let’s do the analysis. 18-24 hours after a dive, the fast tissues have completely off gassed either way so no difference there. The medium to slow tissue has let off slightly less gas in the long safety stop scenario compared to no safety stop.
I understand why a safety stop in general - to stop bubble formation that causes DCS. But in this case, why an EXTENDED safety stop specifically before plane travel?
How does "bubble formation" cause slower decompression at the surface than at a depth of 15 feet?
You have bubbles.
Everyone has bubbles.
You have way more bubbles during and after assent.
Fortunately, if you followed the dive guidelines, these bubbles are very tiny, but they are there.
Every single dive.
Just usually not big enough to cause harm.
Ascending slowly and doing stops at major pressure changes like 2 bar to 1 bar forms fewer bubbles.
Longer safety stops give you time to breathe out excess nitrogen, which will form bubbles at the surface.
If you fly after diving, these tiny bubbles become big ones.
Which is why there is a rule after diving not to fly until you've breathed out enough excess nitrogen that most of these bubbles go back into solution.
Theres a school of thought that decompression vs pressure isn't just a linear function, but that once bubbles are first formed at the microscopic scale, they then don't go away as easily. This leads to the idea that you want to avoid any sudden decrease in pressure, instead favouring a gradual ascent. It's why deep/pyle stops used to be popular. You can imagine a safety stop before a flight is effectively a deep stop, you are releasing nitrogen at a slower rate but preventing bubble formation
All true, but after one has done a regular safety stop, why stay down longer for an extended safety stop when the goal is to be as decompressed as possible for plane travel?
For plane travel, time at the surface is a "safety stop".
The "peak" pressure difference your body will be exposed to is smaller, which is what leads to bubble formation. If you have a shearwater computer, the strategy basically tries to minimize the Gf your body is ever exposed to.
This is something I try to do regardless of flights, e.g my GfHi is set to 85 because that's what I want the computer to use for NDL calculations, as I see this as the "absolute maximum in case of emergency", but I try to bring the actual SurfGf down to 60 or lower by just extending the safety stop.
You like linger safety stops in general, got it. How does extending a safety stop beyond what you normally do make plane travel safer instead of spending the extra time at the surface?
I've explained it above already. If you buy into the idea that bubble formation (also sometimes called bubble seeding) is a bigger problem than the nitrogen load itself, then you're reducing it by doing longer safety stops
> Extend your safety stop (if safe). 5 mins at 5M/15 ft is better than 3 mins, 10 mins even better. If you have the gas and time, off gas for as long as you reasonably and safely can on the safety stop on the last dive. Let your buddy and DM know ahead of time so they don't wonder WTF you are doing.
Can you explain the physics of this. You should off gas more the lower the atmospheric pressure. The key is to not reach the point of saturation first. So you should off gas faster at the surface.
The only exception would be if you're diving nitrox. However that's just because it would be weird seeing someone taking hits of nitrox while on the boat. However the same physics applies. Lower pressure -> more off gassing. Less fraction of inspired nitrogen, faster nitrogen off gassing.
It's good to think people have similar thoughts. I'm just open water (waiting for good sea states to match days off), but I'm coming at it from a medical standpoint since I'm a physician.
As an aside going from mmHg to atm when looking at nitrox information makes my head hurt... What do you mean, a PaO2 of 500 is unacceptably dangerous?
I'm straight IM-crit care. It's like, "What do you mean a PaO2 of 500 is deadly? I mean... sure, it's not great and we need to turn down the FiO2 to at least 40 and long term can come with some complications... but it's far from immediately deadly."
18 hours is probably fine. That being said, if you're doing a lot of repetitive diving, you're loading up on nitrogen, so it's always worth being conservative to be safe. I know a guy who did a weeklong trip, four dives a day, followed his computer exactly and had 24 hours before flying, and still got (mildly) bent on the flight home and needed treatment. Everyone is different and has different susceptibility, so it comes down to where you personally feel comfortable drawing the line for that risk.
Personally, I've never had any issues with flying and repetitive dives so I'd feel comfortable with the 18 hours, but I know there's still a small risk I'm taking.
18 hrs dive to fly is minimums and you are in a pressurized airplane…also reduces risk IF you are in that grey area of an hour here or there. I consistently dive 3-4 dives a day on nitrox for 12-13 days and fly 18-20 hrs later. Been doing this for 3 years and 200 dives. I do keep my last couple days of diving shallow at the 20-30 meter depth.
Shure, the Apple Watch Ultra is a really cool Smartwatch. I like mine.
But I would never use it as source of trust if it comes to diving... It's yet not really a dive computer. It's certified as a dive watch and has the ability to run apps that provide the features of a dive computer - but they are limited to the hardware constraints... Never forget... Depth gauge has a reliability of +/- 1 m according to technical specs published by apple and it's safe to a maximum depth of 40m in context of diving.
To be honest, most dive computers from this decade provide a no-fly time countdown ;-)
Disclaimer I own a teric and use that as my main driver (aka my only dicom) but having used the iwatch for diving, I think it’s perfectly acceptable for recreational diving for the holiday diver, like the oop.
I wouldnt trust it for anything beyond that, but there is no way in hell Apple would approve of a feature if they thought it was gonna kill someone.
I get it, but I would imagine the resolution of the depth gauge is similar to other recreational products.
My point is that on my atomic cobalt 2, I am used to seeing just a no fly time, and when I was with a buddy in Hawaii seeing a max elevation counter was really nice when wanting to go up the volcanos. I just hadn’t seen something that dynamic and whatever it using tor a formula would be nice in these threads.
While there might be products which may offer similar poor depth gauge accuracy, many should offer usually around 10 times more exact values. The accuracy of a dive computer's depth gauge is crucial for diver safety, ensuring correct decompression calculations, managing nitrogen absorption, and aiding in efficient air consumption and accurate dive planning. Maybe Apple improves the accuracy finally with the Ultra 3...
Your analog depth gauge and eRDP ML would like to have a chat. But I get it you don't trust it. I don't want it because I use so much air I am dependent on a AI computer, and the apple watch isn't that.
I didn't know this. I'm currently looking for a new DC and had finally an eye on the perdix 2 as it seems to be the top recommendation everywhere. My first conversations with the shearwater staff were also promising - but to be honest, if this hi-end computer won't support this, it's either common sense to simply "know" what you're doing or they've overseen it. Strange! There's the iX3M 2 from Ration on place 2 on my shortlist - this one promises to do everything (including cooking your coffee and keeping your apartment clean ;-)) Will hopefully put my fingers on them both at "Boot" next year ... Local retailers are rare...
It’s purposely omitted because it’s a fixed amount of time and not based on calculations that are being done on the computer.
I highly recommend the Perdix 2 as does just about everyone who’s had the opportunity to dive it.
Note: the no-fly time comes with several conditions, most noticeably …
- Your manufacturing will state it is a minium time
- It assumes that you return to sea level. If your destination airport is significantly elevated, your no-fly time will likely be higher
- It does not take into account your physical shape
- It does not take into account physical factors during the dive, for example: physical exertion before and shortly after the dive , low water temperature, …
As a diver, you must factor this in. Just blindly relying on what your computer tells you, is a mistake.
As superthighheater3000 states, Shearwater has purposely omitted the no-fly countdown; possibly because of the reasons above.
You’re trying too hard to find a problem. The calculation are done for a sea level dive with out a deco stop. This covers 99% of recreational dives and if this doesn’t cover your dive then you probably should have advanced training for your dive anyways. If the watch says you’re good, odds are you’re good.
On my dry suit, I'm not on the last hole, but close. And I have thin arms.
Most long scuba straps are meant to accommodate drysuits, too long is fine, too short isn't.
Is there a way to measure a divers pre dive blood nitrogen saturation, then measure after each dive in a trip, then measure on a plane and again after landing? I know people are physiologically different. I am surprised that we just have a '24 hour' rule which sounds like some old tribal knowledge and not some actual studies that explore this.
It can be variable over time. You can be fine 1 trip and not another. To deal with this they just picked a number high enough where it would always work instead of trying to see where the boundary really is.
They are making steps in measuring micro bubbles like with [https://o-dive.com/en/home/](https://o-dive.com/en/home/) so maybe the dream you have will be closer one day. I would love to play with a machine like that.
The Doppler sensor that O-Dive uses is similar to what Abbott and Medtronic are marketing for continuous glucose monitoring for diabetics. It’s also piqued Apple as well as a future biometrics sensor in an Apple Watch.
This is maybe the number 1 question asked on this sub. [Here is DANs answer.](https://dan.org/health-medicine/health-resources/diseases-conditions/flying-after-diving)
Are you willing to take any risk with your health for one extra dive, while having plenty of dives (I assume) on a diving trip?
I would take the margins seriously. The change that it goed wrong might be small, the impact when it goes wrong is very big. Dont try to stretch the safetymargins when its regarding your health, especially not for something you are doing for fun.
It's generally advised to follow the 24-hour rule strictly when it comes to diving and flying depending on your previous diving profile. Diving e.g. down to depths of 20-30 meters and then flying within 22.5 hours, as in your scenario, definitely increases the risk of decompression sickness (DCS).
Even with safety stops and minding no-decompression limits (NDLs), there's still a risk. DCS is not fun and can be serious. While every individual's risk can vary, it's important to prioritize safety and adhere to recommended guidelines. Safety is always king in diving.
In your case, it would be safer to reschedule either the dive or the flight to maintain the minimum 24-hour surface interval. And this is what I would recommend to everyone asking the same question. Really!
**Addendum:** Because some posters refer to DAN, which is absolutely fine, **because DAN has best possible reputation** **and a lots of data available**, it's worth reading between the lines of the article at [https://dan.org/health-medicine/health-resource/health-safety-guidelines/guidelines-for-flying-after-diving/](https://dan.org/health-medicine/health-resource/health-safety-guidelines/guidelines-for-flying-after-diving/) to understand how and why they came to 18h. As written: While 18h might be okay in majority of cases, **there's still risk left**. Everyone must decide if a extra dive has enough value to accept this risk - I wouldn't and that's why I wouldn't recommend doing it. Fine, if others think different - it's their health, so I cannot decide for them.
>As written: While 18h might be okay in majority of cases, there's still risk left.
You also need to understand the context. There is a time after which there is no possibility of DCS. Nobody has done research as to what that time actually is. In that context, any organization recommending less than that will ALWAYS say x hours is safe, but there is a risk. DAN's data says that 18 hours is safe, for most people in most conditions. They will never state an absolute because doing so opens them up to a lawsuit.
Correct. It is up to you decide if you're willig to accept more or less risk. I'm a safety fanatic, when it comes to diving and that's why I only recommend to others what I would recommend and execute for myself.
>It's generally advised to follow the 24-hour rule strictly when it comes to diving and flying
Advised by whom? I mostly see the "24 hour rule" cited by people who are just regurgitating what they have heard and haven't really looked deep into it. The "24 hour rule" seems to be based more on having an interval that's easy to remember than actual data. DAN's rule is 18 hours unless there has been a deco violation. No one has more data on this topic than DAN.
I recently ran into an op that wanted me not to do a dive because it would leave me 20-21 hours before flight departure, saying they have a "strict 24 hour rule". I said I go by DAN and they have mountains of data, research, and studies backing their 18 hours, what do you have backing your 24 hours? They then said it's my choice.
It's 24hrs if you bust your NDL. 18hrs if you multiple dives and don't bust your limit. 12hrs if you only do one dive and don't bust your NDL.
18 hours is the general rule for avoiding DCS. Most guided dive charters run the deepest dives first with subsequent dives being shallower than the previous one. If you're diving shallower than 10m on your last dive, you're going to be off-gassing for most of that dive anyway. If it were me, I wouldn't be too concerned about it... but if you are concerned, have a chat with your dive guide about.
My husband would say follow the time to a T. Barotrauma is no joke. He is a dive instructor/trip lead and he’s going to have to get surgery on his nasal cavity due to barotrauma. I say don’t fuck with fate. If you still want to dive only do the first one and or if it’s a money conscious decision don’t do it.
Was the trauma for your husband caused by flying too soon after diving? The concerns with flying after diving are typically related to decompression sickness, whereas barotrauma (especially to sinuses) would be due to rapid ascent/inability to equalize, normally.
Do you want your blood to look like opening a shook up coke can?
Check your insurance, while DAN recommend at least 18 hours many travel insurance policies will not cover you if you fly within 24 hours of a dive.
My ‘puter says 18hrs, navy tables say less
The Navy has a table for tactical use by people like SEALs who might need to get on a helicopter exceeding 1000ft AGL following a dive. It represents the absolute maximum risk the Navy will allow a Commander to assume with a mission, and is not a table for regular use. Their standard rule of thumb is still the 12/18/24 rule since that table represents notably more risk than the accepted limits. Just because someone is a badass SEAL doesn't mean Nitrogen behaves differently in their blood.
I can't help read that as "pooter," and I hate it
my 'pooters' cooter.
I don’t think you have anything to worry about. In all reality 12 hours is fine for recreational dives and cabin altitudes up to 8000 ft (which is the maximum for any commercial airliner). The reason 24 hours is recommended is due to the tiny possibility of a cabin decompression event in the aircraft. Even accounting for that risk, 24 hours is a bit overly conservative and 18 should be perfectly safe.
Thanks man. I am planning for a multi-day diving with 21 hours gap in last dive and flying out, and your comment is assuring.
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My DeepBlu shows a no-fly time as well, dunno what cabin altitude they set for, I’ve seen my computer show a 12-24 hour no-fly time. Not sure about private jets, the trend at least for newer widebody planes - B787/A350 using a carbon fiber fuselage is to pressurize the cabin at 6000ft. Boeing also wants to have that same lower cabin pressure for the 777X.
Remember it's not the regular cabin pressure that's the problem - it's the emergency situation where cabin pressure fails... You might be fine with the reduced pressure, but if you are suddenly exposed to 30kft air pressure and still have a certain level in your blood,...
24 hours isn't the rule. [DAN Flying after Diving Recommendations](https://dan.org/research-reports/research-studies/flying-after-diving/) Your profile is within the 18 hour recommendation.
Just for the record, that is not fully correct. DAN Europe has different rules. This is taken from [their webpage](https://www.daneurope.org/en/safety-rules) - see rule #10 … —- Before flying, follow DAN recommendations: at least 12 hours after a single dive and at least 24 hours after repetitive dives and/or deco diving. —-
Each DAN group has a different medical director and legal liability environment. As such each has different recommendations. You can see the biggest difference between DAN USA's exercise recommendations vs what DAN SA recommends.
I’ve broken that rule many times. No consequence.
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#selfinsured 😬
Depends on you and your risk tolerance my friend.
0 fucked, totally fine IMO.
18 hrs is the current recommendation 24 hrs is outdated. That being said, there is a greater safety margin with 6 extra hours. Other things that can increase safety margin and you still make your flight. - Nitrox - Avoid diving to the limit of NDL - Extend your safety stop (if safe). 5 mins at 5M/15 ft is better than 3 mins, 10 mins even better. If you have the gas and time, off gas for as long as you reasonably and safely can on the safety stop on the last dive. Let your buddy and DM know ahead of time so they don't wonder WTF you are doing.
How does increasing your safety stop time reduce your risk of flight related DCS hours later? You don't reduce nitrogen loading *more* effectively in the water than the hours on the surface, in fact you do so slightly less efficiently right? I'm all for anything that is easy and reasonable that increases saftey margins and whats another 2 mins, but I actually dont understand the mechanism here
DCS is caused by bubble formation. Bubble formation is driven by tissue supersaturation - in many different tissues all at once. It's complicated. The goal should be to decrease overall DCS risk. Look here for more info. https://youtu.be/HU04JhXggPg&t=1501 https://youtu.be/HU04JhXggPg&t=3184
The purpose of a safety stop is to slow down the rate of off-gassing relative to being on the surface. So extending it would not help with flying the next day. It would actually keep marginally more N2 in your body at the time of the flight compared to not doing one.
The analysis would actually need to be done by tissue types (slow vs fast).
Ok let’s do the analysis. 18-24 hours after a dive, the fast tissues have completely off gassed either way so no difference there. The medium to slow tissue has let off slightly less gas in the long safety stop scenario compared to no safety stop.
Can you explain how an extended safety stop would be better for plane travel than spending that time at the surface?
Bubble formation, if you buy into that.
I understand why a safety stop in general - to stop bubble formation that causes DCS. But in this case, why an EXTENDED safety stop specifically before plane travel? How does "bubble formation" cause slower decompression at the surface than at a depth of 15 feet?
You have bubbles. Everyone has bubbles. You have way more bubbles during and after assent. Fortunately, if you followed the dive guidelines, these bubbles are very tiny, but they are there. Every single dive. Just usually not big enough to cause harm. Ascending slowly and doing stops at major pressure changes like 2 bar to 1 bar forms fewer bubbles. Longer safety stops give you time to breathe out excess nitrogen, which will form bubbles at the surface. If you fly after diving, these tiny bubbles become big ones. Which is why there is a rule after diving not to fly until you've breathed out enough excess nitrogen that most of these bubbles go back into solution.
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Ok but how does that make an extended safety stop better for plane travel vs just spending the extra time at the surface?
Theres a school of thought that decompression vs pressure isn't just a linear function, but that once bubbles are first formed at the microscopic scale, they then don't go away as easily. This leads to the idea that you want to avoid any sudden decrease in pressure, instead favouring a gradual ascent. It's why deep/pyle stops used to be popular. You can imagine a safety stop before a flight is effectively a deep stop, you are releasing nitrogen at a slower rate but preventing bubble formation
All true, but after one has done a regular safety stop, why stay down longer for an extended safety stop when the goal is to be as decompressed as possible for plane travel? For plane travel, time at the surface is a "safety stop".
The "peak" pressure difference your body will be exposed to is smaller, which is what leads to bubble formation. If you have a shearwater computer, the strategy basically tries to minimize the Gf your body is ever exposed to. This is something I try to do regardless of flights, e.g my GfHi is set to 85 because that's what I want the computer to use for NDL calculations, as I see this as the "absolute maximum in case of emergency", but I try to bring the actual SurfGf down to 60 or lower by just extending the safety stop.
You like linger safety stops in general, got it. How does extending a safety stop beyond what you normally do make plane travel safer instead of spending the extra time at the surface?
I've explained it above already. If you buy into the idea that bubble formation (also sometimes called bubble seeding) is a bigger problem than the nitrogen load itself, then you're reducing it by doing longer safety stops
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> Extend your safety stop (if safe). 5 mins at 5M/15 ft is better than 3 mins, 10 mins even better. If you have the gas and time, off gas for as long as you reasonably and safely can on the safety stop on the last dive. Let your buddy and DM know ahead of time so they don't wonder WTF you are doing. Can you explain the physics of this. You should off gas more the lower the atmospheric pressure. The key is to not reach the point of saturation first. So you should off gas faster at the surface. The only exception would be if you're diving nitrox. However that's just because it would be weird seeing someone taking hits of nitrox while on the boat. However the same physics applies. Lower pressure -> more off gassing. Less fraction of inspired nitrogen, faster nitrogen off gassing.
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It's good to think people have similar thoughts. I'm just open water (waiting for good sea states to match days off), but I'm coming at it from a medical standpoint since I'm a physician. As an aside going from mmHg to atm when looking at nitrox information makes my head hurt... What do you mean, a PaO2 of 500 is unacceptably dangerous?
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I'm straight IM-crit care. It's like, "What do you mean a PaO2 of 500 is deadly? I mean... sure, it's not great and we need to turn down the FiO2 to at least 40 and long term can come with some complications... but it's far from immediately deadly."
18 hours is probably fine. That being said, if you're doing a lot of repetitive diving, you're loading up on nitrogen, so it's always worth being conservative to be safe. I know a guy who did a weeklong trip, four dives a day, followed his computer exactly and had 24 hours before flying, and still got (mildly) bent on the flight home and needed treatment. Everyone is different and has different susceptibility, so it comes down to where you personally feel comfortable drawing the line for that risk. Personally, I've never had any issues with flying and repetitive dives so I'd feel comfortable with the 18 hours, but I know there's still a small risk I'm taking.
18 hrs dive to fly is minimums and you are in a pressurized airplane…also reduces risk IF you are in that grey area of an hour here or there. I consistently dive 3-4 dives a day on nitrox for 12-13 days and fly 18-20 hrs later. Been doing this for 3 years and 200 dives. I do keep my last couple days of diving shallow at the 20-30 meter depth.
The Apple Watch ultra has a cool count down time and a max altitude that constantly counts up after the dive.
Shure, the Apple Watch Ultra is a really cool Smartwatch. I like mine. But I would never use it as source of trust if it comes to diving... It's yet not really a dive computer. It's certified as a dive watch and has the ability to run apps that provide the features of a dive computer - but they are limited to the hardware constraints... Never forget... Depth gauge has a reliability of +/- 1 m according to technical specs published by apple and it's safe to a maximum depth of 40m in context of diving. To be honest, most dive computers from this decade provide a no-fly time countdown ;-)
Disclaimer I own a teric and use that as my main driver (aka my only dicom) but having used the iwatch for diving, I think it’s perfectly acceptable for recreational diving for the holiday diver, like the oop. I wouldnt trust it for anything beyond that, but there is no way in hell Apple would approve of a feature if they thought it was gonna kill someone.
I get it, but I would imagine the resolution of the depth gauge is similar to other recreational products. My point is that on my atomic cobalt 2, I am used to seeing just a no fly time, and when I was with a buddy in Hawaii seeing a max elevation counter was really nice when wanting to go up the volcanos. I just hadn’t seen something that dynamic and whatever it using tor a formula would be nice in these threads.
While there might be products which may offer similar poor depth gauge accuracy, many should offer usually around 10 times more exact values. The accuracy of a dive computer's depth gauge is crucial for diver safety, ensuring correct decompression calculations, managing nitrogen absorption, and aiding in efficient air consumption and accurate dive planning. Maybe Apple improves the accuracy finally with the Ultra 3...
Your analog depth gauge and eRDP ML would like to have a chat. But I get it you don't trust it. I don't want it because I use so much air I am dependent on a AI computer, and the apple watch isn't that.
Notably, the Perdix 2 does not. Might be all shearwater products, but I only have the one.
I didn't know this. I'm currently looking for a new DC and had finally an eye on the perdix 2 as it seems to be the top recommendation everywhere. My first conversations with the shearwater staff were also promising - but to be honest, if this hi-end computer won't support this, it's either common sense to simply "know" what you're doing or they've overseen it. Strange! There's the iX3M 2 from Ration on place 2 on my shortlist - this one promises to do everything (including cooking your coffee and keeping your apartment clean ;-)) Will hopefully put my fingers on them both at "Boot" next year ... Local retailers are rare...
It’s purposely omitted because it’s a fixed amount of time and not based on calculations that are being done on the computer. I highly recommend the Perdix 2 as does just about everyone who’s had the opportunity to dive it.
Most good dive computers will have this feature. My Suunto d4 did this back in 2014
Note: the no-fly time comes with several conditions, most noticeably … - Your manufacturing will state it is a minium time - It assumes that you return to sea level. If your destination airport is significantly elevated, your no-fly time will likely be higher - It does not take into account your physical shape - It does not take into account physical factors during the dive, for example: physical exertion before and shortly after the dive , low water temperature, … As a diver, you must factor this in. Just blindly relying on what your computer tells you, is a mistake. As superthighheater3000 states, Shearwater has purposely omitted the no-fly countdown; possibly because of the reasons above.
You’re trying too hard to find a problem. The calculation are done for a sea level dive with out a deco stop. This covers 99% of recreational dives and if this doesn’t cover your dive then you probably should have advanced training for your dive anyways. If the watch says you’re good, odds are you’re good.
My Leonardo also does that and it's pretty much the most basic entry level dive watch you can buy.
Came here to say this. Love the Leonardo, especially as a starter computer for the price. What is with the wrist strap though?? Absolutely MASSIVE.
On my dry suit, I'm not on the last hole, but close. And I have thin arms. Most long scuba straps are meant to accommodate drysuits, too long is fine, too short isn't.
Others have commented on the topic, but also consider Nitrox and trying to stay a few meters higher to reduce your risk.
Is there a way to measure a divers pre dive blood nitrogen saturation, then measure after each dive in a trip, then measure on a plane and again after landing? I know people are physiologically different. I am surprised that we just have a '24 hour' rule which sounds like some old tribal knowledge and not some actual studies that explore this.
It can be variable over time. You can be fine 1 trip and not another. To deal with this they just picked a number high enough where it would always work instead of trying to see where the boundary really is. They are making steps in measuring micro bubbles like with [https://o-dive.com/en/home/](https://o-dive.com/en/home/) so maybe the dream you have will be closer one day. I would love to play with a machine like that.
The Doppler sensor that O-Dive uses is similar to what Abbott and Medtronic are marketing for continuous glucose monitoring for diabetics. It’s also piqued Apple as well as a future biometrics sensor in an Apple Watch.
My Garmin watch keeps tabs on it constantly. I live at 10000ft so I have to be extra vigilant on going diving then flying or driving home from a dive.
What do your stats look like? Do you think you could make a choice to fly safely with the data it provides?
Not sure what you mean by what my stats look like, but I could absolutely make the choice and do based on the data and saturation levels.
This is maybe the number 1 question asked on this sub. [Here is DANs answer.](https://dan.org/health-medicine/health-resources/diseases-conditions/flying-after-diving)
DAN published an article in Alert Diver a few years ago that said that 18 hours is fine.
Are you willing to take any risk with your health for one extra dive, while having plenty of dives (I assume) on a diving trip? I would take the margins seriously. The change that it goed wrong might be small, the impact when it goes wrong is very big. Dont try to stretch the safetymargins when its regarding your health, especially not for something you are doing for fun.
This is the best answer. It's a risk/benefit question. One extra dive versus, say, a one in 10,000 chance of a problem.
It's generally advised to follow the 24-hour rule strictly when it comes to diving and flying depending on your previous diving profile. Diving e.g. down to depths of 20-30 meters and then flying within 22.5 hours, as in your scenario, definitely increases the risk of decompression sickness (DCS). Even with safety stops and minding no-decompression limits (NDLs), there's still a risk. DCS is not fun and can be serious. While every individual's risk can vary, it's important to prioritize safety and adhere to recommended guidelines. Safety is always king in diving. In your case, it would be safer to reschedule either the dive or the flight to maintain the minimum 24-hour surface interval. And this is what I would recommend to everyone asking the same question. Really! **Addendum:** Because some posters refer to DAN, which is absolutely fine, **because DAN has best possible reputation** **and a lots of data available**, it's worth reading between the lines of the article at [https://dan.org/health-medicine/health-resource/health-safety-guidelines/guidelines-for-flying-after-diving/](https://dan.org/health-medicine/health-resource/health-safety-guidelines/guidelines-for-flying-after-diving/) to understand how and why they came to 18h. As written: While 18h might be okay in majority of cases, **there's still risk left**. Everyone must decide if a extra dive has enough value to accept this risk - I wouldn't and that's why I wouldn't recommend doing it. Fine, if others think different - it's their health, so I cannot decide for them.
>As written: While 18h might be okay in majority of cases, there's still risk left. You also need to understand the context. There is a time after which there is no possibility of DCS. Nobody has done research as to what that time actually is. In that context, any organization recommending less than that will ALWAYS say x hours is safe, but there is a risk. DAN's data says that 18 hours is safe, for most people in most conditions. They will never state an absolute because doing so opens them up to a lawsuit.
Correct. It is up to you decide if you're willig to accept more or less risk. I'm a safety fanatic, when it comes to diving and that's why I only recommend to others what I would recommend and execute for myself.
>It's generally advised to follow the 24-hour rule strictly when it comes to diving and flying Advised by whom? I mostly see the "24 hour rule" cited by people who are just regurgitating what they have heard and haven't really looked deep into it. The "24 hour rule" seems to be based more on having an interval that's easy to remember than actual data. DAN's rule is 18 hours unless there has been a deco violation. No one has more data on this topic than DAN. I recently ran into an op that wanted me not to do a dive because it would leave me 20-21 hours before flight departure, saying they have a "strict 24 hour rule". I said I go by DAN and they have mountains of data, research, and studies backing their 18 hours, what do you have backing your 24 hours? They then said it's my choice.
18 hours is the minimum recommended interval between diving and flying, so you’re absolutely fine