When to do a safety stop?

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I have my dive computer set to the most conservative setting. Spending time below about 30’ is the threshold where it will trigger a safety stop requirement. That being said, I end up proactively doing a safety stop if I spend much time at all below “safety stop” depth, even if the computer doesn’t call for it.

If you’re doing a 10’-20’ dive (I had one like that this past Friday), then no...I’m not doing a safety stop.
 
So, I've seen blanket statements that you should always do a safety stop. However, this can't really be the case. If I'm diving in 10-12' of water, surely I don't descend to 15', wait 3 mins and then ascend.

I feel sure that at 60' I would do a safety stop, but what about less than 33'? And even in-between; would you do a safety stop at 40'?

I want to be safe but also not ridiculous. Thanks for your help
To answer your question. No, if the dive is shallower then it isn’t necessary.

The stop is a ‘safety stop’ not a ‘mandatory stop’. it accomplishes a number of purposes, one being; to control the ascent by ensuring you can stop.
 
I dove for 17 years before one of the certifying agencies began to recommend safety stops around 1984. Even then, most of our group didn't give it much thought even after longer and deeper dives. I started doing them sometime in the 1990's but only on dives over 30 feet. I guess my point is that they are a good idea but IMHO not really necessary on shallow dives. Now where did I put my wheelchair, cane and backbrace... :)
 
You do not need to do a safety stop above 35 feet, below that it is not a bad idea to do a 3-5 minutes safety stop or longer after keepers dives. Don't forget too look around during the stop I have had some really cool encounters on safety stops including many sea turtles, a Mako shark, dolphins and a scary cool encounter with a bait ball where I ended up going through the middle of it! Just make sure that you have enough air to make the stop.
 
Above 30 naw, below 30 sure. What you got to lose other than some air in your tanks.

And if you aren't filling your own, what you would rather take it back to the shop, or stay wet a few more minutes.
 
that said.....technically speaking.....a safety stop is a "recommendation", it is not a "requirement".
Even more technically speaking, a safety stop can't hurt.

one last suggestion.....when you do a stop, do not just race to the surface after the time is up. practice ascending as slow as possible. not only is it good buoyancy control practice but it is the greatest relative pressure change, so take your time.
THIS is the most important thing posted in this thread so far! Any value from a safety stop is negated by racing to the surface afterwards. What is racing? Taking less than 30 seconds to ascend from 15 ft. Even slower is better.
 
No reason not to unless its going to compromise your safety. I usually hang out for longer than 3 minutes if I have the time and air supply. As mentioned before, memorable sightings happen at the safety stop, especially when you are the last pair in the water. First time I saw a Hammerhead was at a safety stop in Turks and Caicos, everyone else on the boat was very jealous. It's also a great time to practice holding depth in the deep blue, with few visual references.
 
Even more technically speaking, a safety stop can't hurt.


THIS is the most important thing posted in this thread so far! Any value from a safety stop is negated by racing to the surface afterwards. What is racing? Taking less than 30 seconds to ascend from 15 ft. Even slower is better.
I generally do the ‘jaws’ music in my head when the safety stop is up from 15ft and surface on the ‘du NUH NUUURRHHH!’
 
I hesitate to write this because so few recreational divers have the right equipment for it, but some computers can give you real insight into the need. Since I have such computers, I will describe how it has changed my personal procedures and what I have learned about safety stops from following those procedures. That learning may be instructive to people without those computers.

The idea of a slow ascent during an NDL dive is to allow tissues to off-gas enough nitrogen to make it safe to go to the surface and the greatly reduced pressure there. The last 10-20 feet of the ascent is when pressure drops dramatically, so the idea of stopping at that level for a few minutes just to be sure was developed, and that is the purpose of the safety stop. Some modern computers will give you a reading of what your surfacing pressure will be relative to that theoretical maximum safe pressure (gradient factor) if you were to surface at that moment. In theory, that will tell you how necessary it will be to do a safety stop, or how long to do it. If the reading (surfGF) is 70, then if you were to surface at that moment, the nitrogen pressure in your tissues would be about 70% of what is considered safe, so that would be considered a pretty safe pressure. If you were to arrive at safety stop depth with a surfGF of 70, you would probably not have much of a need for a safety stop.

So after doing this for a while, I see that if I do not come all that close to the NDL on a mid range dive (say 70-90 feet), I don't really need one. If I do get close to NDL on such a dive, then the typical 3-5 minute stop will get me to a nice, safe range. In general, if I get within a few minutes of NDL on ANY dive, a safety stop does a pretty good job.

Note that I am using how close you get to NDL as a metric rather than depth. That is because I dive mostly with nitrox. (The place in Florida where I get my tanks filled where I do my NDL diving gives me nitrox for a good price, so why not?) This past winter I did a number of shallower (50-60 feet) reef dives with friends, and we did those dives with EANx 36. Those dives lasted an hour (by captain's orders), and when we reached safety stop depth, my friends' computers started counting off their safety stops. The surfGF reading on my computer was usually 45-50 at that point, meaning we were only about halfway to the highest safe pressure for surfacing when we started that safety stop. I stayed with them for those stops, of course, but they were completely unnecessary except for the fact that their computers were requiring it.
 
I found myself getting very complacent about safety stops because most of my shore dives, the last part of the dive would be shallow as I got closer to shore. That seems reasonable, when I spend 15 minutes at 20' to not do a safety stop.

But complacency creeps up - if my 50' max depth dive ended around 30' I would often just blow the safety stop. Probably not a big deal, but this is how standards are ignored.

So now I've made a conscious effort to do safety stops. If my computer says do a stop, I do a stop. So Ive found im doing stops where max depth 40' and I spent the last half of the dive around 25' or so.

Better to be cautious than cavalier about it.
 

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