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CheatinDeath
09-01-2007, 15:28
I have a question. I was told this summer by a divemaster (in the U.S.)that since we were going to be doing shallow diving (30 ft max), that the "new" PADI rules said the safety stop was 1 minute.

I have found no reference to this in all of my material and online search, and was wondering if anyone knows if PADI has changed their stance on the 3-5 min safety stop at 15 ft?

finflippers
09-01-2007, 15:35
This is news to me.

I will still be doing my minimum 3 minutes for shallow or longer for more indepth or deeper dives.

scubasamurai
09-01-2007, 15:38
as far as i know still doing it at 15ft /5meters. 3 to 5 minutes or depending if you blew any limits. at that depth i go up slow and if i am bored i do the stop, but i usually do safety stops anything greater than 40 ft and if i been down for more than 30 minutes at depths less than 40 feet for good measure
but the rule safety stop 15ft/3mins

in_cavediver
09-01-2007, 16:43
First, the idea of a safety stop has two purposes. The first is to stop the ascent before hitting the 'critical' area of the ascent - IE the last 10'-20'. The second part is to provide a cushion deco stop. Its optional deco so they don't call it a stop.

Now, here's another interesting question, can you get bent in the first 33ft of the water column? According to many models you can't. In which case, the safety stop is simply to control the ascent.

Your opinions may vary.

WV Diver
09-01-2007, 16:53
No such new PADI standards have some across my desk.

Recreational NDL's do not dictate a safety stop, but any safety stop, unless you run out of air while doing it, will not hurt. Err on the side of caution. It probably would not hurt you doing shallow NDL diving to ascend without any SS, but why take a chance.

This DM either didn't know what he was talking about or had a hot date and figured 2 extra minutes would ruin it. Remember, ultimately you are responsible for yourself, do not follow anyone blindly if you are in doubt.

Hemlon
09-01-2007, 16:59
I haven't heard of a change to the safety stop requirement.

georoc01
09-01-2007, 17:37
If anything, I have been hearing the reverse, that the three minute rule is being upped to five minutes. I wonder if there is a way to update my computer, I love the countdown when I get to 15 ft.

scubasamurai
09-01-2007, 18:00
you never know , heard some diver shot up from 30 ft and did get bent, but did survive with minimal affect. not too sure how true the story is, maybe it is an instructor trick to get us to do our safety stop

plot
09-01-2007, 18:34
maybe the DM doesn't like you? either that or he was PADI bashing by making fun of how lenient they are and you just didn't catch on ;)

scubasamurai
09-01-2007, 18:52
neither i would guess, she, yes a women, does like me :smiley32:. but i think she was trying to instill some "fear' if we don;t follow the procedure tilll we get more dives in :smiley29:

but bash all you want , i am having fun :smilie39:

plot
09-01-2007, 19:31
neither i would guess, she, yes a women, does like me :smiley32:. but i think she was trying to instill some "fear' if we don;t follow the procedure tilll we get more dives in :smiley29:

but bash all you want , i am having fun :smilie39:

:bash:

cudachaser
09-01-2007, 20:13
I believe the Safety Stop is DAN recommendation to the RSTC...It's not a "PADI Innovation"

Our NASE table rules (Which are based on Navy Doppler Data) clearly state that a 3 to 5 min stop will be conducted at the termination of the dive.

in_cavediver
09-01-2007, 21:43
you never know , heard some diver shot up from 30 ft and did get bent, but did survive with minimal affect. not too sure how true the story is, maybe it is an instructor trick to get us to do our safety stop

Shooting up is more like an embolism not a bend. Different issue and yes, its VERY possible to embolize in 5 feet of water, let alone 30.

The reason many claim a safety stop is not needed in less than 30ft of water come from the Haldanean tissue model based decompression algorithm (and actually, all tissue models, the Haldane is what DSAT/PADI tables use as well as several brands of computers such as genesis and oceanic). The idea is to divide the human body into a number of 'tissue compartments'. Each compartment is characterized by a specific ongassing rate (exponential rate usually), off gassing rate (again usually exponential but have variants), and a max gradient differential.

Its the last part, the max tissue saturation/gradients that come into play in the less the 30ft dives. In some models, you can fully saturate your tissues to the ambient pressures (at 30ft) with N2 and not exceed the surfacing gradient or M0 value, therefore, its not possible to get bent. (Tissues will absorb only so much N2 given an ambient PN2).

All of that said, there is absolutely nothing wrong with stopping for safety stop after every dive. On deeper (sub 60') dives, its even more of a good idea.

BuzzGA
09-01-2007, 22:45
In addition to safety the way I look at is another three minutes in the water and living in AZ I'll take all the time I can get

Zenagirl
09-02-2007, 07:45
We rarely do 3 min stops anymore.....they are all at least 5 min. ;) Not only does the longer stop give us more time to off gas, but we simply enjoy watching the blue water for big stuff swimming by. Thus far we've been treated to turtles, manta rays, eagle rays, and a few sharks.

scubasamurai
09-02-2007, 08:54
you never know , heard some diver shot up from 30 ft and did get bent, but did survive with minimal affect. not too sure how true the story is, maybe it is an instructor trick to get us to do our safety stop

Shooting up is more like an embolism not a bend. Different issue and yes, its VERY possible to embolize in 5 feet of water, let alone 30.

The reason many claim a safety stop is not needed in less than 30ft of water come from the Haldanean tissue model based decompression algorithm (and actually, all tissue models, the Haldane is what DSAT/PADI tables use as well as several brands of computers such as genesis and oceanic). The idea is to divide the human body into a number of 'tissue compartments'. Each compartment is characterized by a specific ongassing rate (exponential rate usually), off gassing rate (again usually exponential but have variants), and a max gradient differential.

Its the last part, the max tissue saturation/gradients that come into play in the less the 30ft dives. In some models, you can fully saturate your tissues to the ambient pressures (at 30ft) with N2 and not exceed the surfacing gradient or M0 value, therefore, its not possible to get bent. (Tissues will absorb only so much N2 given an ambient PN2).

All of that said, there is absolutely nothing wrong with stopping for safety stop after every dive. On deeper (sub 60') dives, its even more of a good idea.

if there was any nitrogen in the system it could still be related to dcs, even though the "bubble" did block the blood supply to a vital part. for a true emboli affect there would have to be air introduced in the blood stream, ie pneumothorax, of some kind. the nitrogen came out of the tissue and need time to return to the tissue, where as an emboli, air or another object, was actually introduced in to the system.
all in all either way there was still an injury results from an uncontrolled ascent. a safety stop is a good thing to practice no matter who "requires" it.

CompuDude
09-04-2007, 15:06
They recommend full safety stops for all dives, I have not heard of anything from PADI changing that.

However, I'll admit that I don't bother with one for dives that never reach 40', with the majority at 30' and under .

That said, I don't think I have ever done a dive that meets that profile that wasn't a shore dive, where significant time was spent approaching the surf zone in the 10-20' range, effectively spending the last 5-10 minutes in the same zone as a "moving safety stop" anyway.

techgnostic
09-04-2007, 18:42
A few months ago, when I was late to get home, I unclicked my seatbelt a few blocks from my driveway (don't ask my why, I just did it). Not only was it a bad idea, but now, for some reason, I have an unconscious urge to repeat that mistake every time a return to the nest. The mind is funny thing. :smiley11:

I have no wish to start another bad muscle memory. I'll be taking my full safety stop.