Required Safety Stop a decompression stop?

[notrab]

Hi All,

Forgive me if this has already been covered. When the RDP lists a required safety stop is this essentially a decompression stop?

Thanks,
Sean

 

[DuckyDiver]

No, a required satey stop is just that. I beleve, technicaly your still in the NDL and can still assend to the surface without stoping. I becomes 'REQUIRED" because you have gone below a certain depth or come close the the NDL.
Basicaly is a very good idea to always do a safety stop, but if something happens where you can't. Its still ok.

This is my understanding of it.

 

[jvilalta]

The safety stop is not a required decompression stop, in the sense that if you skip it you are not at an increased risk for DCS if you are within the limits of the table. However, it does allow your body to offgas, so technically it is a decompression stop.

 

[Reg Braithwaite]

Here are some things I wonder about:

• Are all dives decompression dives since on all dives I on-gas Nitrogen and must off-gas it at some point?
• What is more important on a "recreational dive"? Ascent speed or a safety stop?
• I read on the Internet that the safety stop was put in the tables because divers were either ignoring or lacked the skills to ascend at the table's recomended rate, so stopping them at 15' would slow them down. is this true? If so, is there any empirical evidence that safety stops matter for people ascending according to the table's ascent rate?
• Why 15'? Why not 10'? Or 20'? Do surface conditions such as waves or swells have anything to do with this? How about buoyancy skills? If you could hold a stop at 10' +/- 2' would it be better than 15'+/- 2'? What if you tried to hold a stop at 10' +/- 5'? Is that worse than 15' +/- 5'?
• Is a slow ascent more important near the surface, half way up the ascent, one quarter of the way up the ascent, or near the bottom. Why?
• Some tech divers were talking about deco the other day and they said that older deco protocols had them decompressing at the surface, while newer deco protocols have them decompressing in the water. What does this mean, and does it have any relevance for recreational diving?

 

[Rick Inman]

A couple of things that "they" say seem to contradict each other.

• A safety stop is not a decompression stop.
• Every dive is a deco dive.

When I first learned to dive, there were no safety stops. We just dived, ascended slower than our bubbles and got back in the boat. Today I see people do 20 mins at 20' and then do a 3 min safety stop. Both kinds of diving show a lack of thinking through the reason for ascending at a specific rate.

Off gassing doesn't suddenly begin at 15'. And you can't off gas what you haven't on gassed. The goal is to get out clean - breath off the excess nitrogen below the surface. And there are many ways to do that.

GUE has an excellent system that has a diver beginning the off gassing process at 80% of max depth and then doing short stops every ten feet on the way up.

Your question shows you want to know more about managing your profile. Good for you! With a little searching here on ScubaBoard, you will discover an encyclopedia of knowledge on the subject.

The "safety stop" is not a deco stop, unless you need it to off gas so you can ascend safely, and that would be dive specific.

 

[Walter]

A safety stop is not required. If the stop is required, it's a decompression stop.

 

[Reg Braithwaite]

A safety stop is not required.

Nevertheless, I and many other OW divers were taught that for certain profiles, a "safety stop" is "required." So by your statement, either the agency is wrong to call it a safety stop or the agency is wrong to tell us it is required.

If the stop is required, it's a decompression stop.

Do I infer from this that you are saying the problem is the nomenclature and therefore the required stop is actually a decompression stop? If so, the answer to the OP's question would seem to be "yes." Is that what you are saying?

 

[notrab]

On the PADI RDP tables even though the max bottom times specify no deco limit they also indicate that a 3 min safety stop is required. Just curoius more than anything why they don't call it a deco stop if they consider it required. In fact, on the RDP, any dive over 100' calls for a required 3 min safety stop at 15'. I just find it misleading to not call it a deco stop if it's required...

 

[Joe-Diver]

I just find it misleading to not call it a deco stop if it's required...

2 things:

1. PADI teaches no stop (no decompression diving) diving with a recreational model. So, if you miss it.....it's not like missing a stop when deco diving. It's "required" only to impress on you how important it is to add that safety cushion when diving near the model limits. Especially now that research into the RGBM model discovered micro bubble nucleation with doppler flows.

2. Semantics. If we profess no stop, no decompression diving....it's silly to put in a deco stop. Some lawyer, somewhere, would use that in accident litigation.

 

[jtivat]

Here are some things I wonder about:

• Are all dives decompression dives since on all dives I on-gas Nitrogen and must off-gas it at some point?
• What is more important on a "recreational dive"? Ascent speed or a safety stop?
• I read on the Internet that the safety stop was put in the tables because divers were either ignoring or lacked the skills to ascend at the table's recomended rate, so stopping them at 15' would slow them down. is this true? If so, is there any empirical evidence that safety stops matter for people ascending according to the table's ascent rate?
• Why 15'? Why not 10'? Or 20'? Do surface conditions such as waves or swells have anything to do with this? How about buoyancy skills? If you could hold a stop at 10' +/- 2' would it be better than 15'+/- 2'? What if you tried to hold a stop at 10' +/- 5'? Is that worse than 15' +/- 5'?
• Is a slow ascent more important near the surface, half way up the ascent, one quarter of the way up the ascent, or near the bottom. Why?
• Some tech divers were talking about deco the other day and they said that older deco protocols had them decompressing at the surface, while newer deco protocols have them decompressing in the water. What does this mean, and does it have any relevance for recreational diving?

You wonder too much!