Two safety stops?

[eelnoraa]

I use GUE min deco ascent profile for dive with max depth of 100ft:
1. ascent with 30ft/min rate to half of max depth
2. spend 1 min at half max depth
3. ascent with rate of 10ft/30section, then stop for 30 second for every 10ft. This is effectlively 10ft/min ascent rate.

For a 100ft dive, I make 5 stops, 1min at 50ft, 30 second at 40, 30, 20, 10. It take some pratice to hold a 10ft and 20ft stop tho.

 

[nimoh]

I use GUE min deco ascent profile for dive with max depth of 100ft:
1. ascent with 30ft/min rate to half of max depth
2. spend 1 min at half max depth
3. ascent with rate of 10ft/30section, then stop for 30 second for every 10ft. This is effectlively 10ft/min ascent rate.

For a 100ft dive, I make 5 stops, 1min at 50ft, 30 second at 40, 30, 20, 10. It take some pratice to hold a 10ft and 20ft stop tho.

me too.

As was mentioned earlier, the safety stop was introduced to slow a diver's ascent during the final ascent in shallow water since many divers were ascending too fast, and in the last 15' it is critical to go slow. The GUE min deco profile makes it easier to slow down your entire ascent to a proper rate. All you have to do is stop every 10' and count to 30 (don't even need to look at your timer).

 

[billt4sf]

I use GUE min deco ascent profile for dive with max depth of 100ft:
1. ascent with 30ft/min rate to half of max depth
2. spend 1 min at half max depth
3. ascent with rate of 10ft/30section, then stop for 30 second for every 10ft.

This is effectlively 10ft/min ascent rate.

Nice!

 

[Abdullah]

Another way to look at the deeper safety stop is the point at which your ascent rate slows (a waypoint). The ascent rate below the waypoint is significantly faster than the ascent rate above the waypoint. The ascent rate to the surface after you've completed your shallow safety stop (another waypoint) should be even slower than the ascent rate you used to get there.

Assuming your deeper stop is above the point at which you begin to off gas (ceiling), there isn't a disadvantage to pausing for a minute before continuing your ascent at the slower rate. Half your average bottom depth should be a good rule of thumb that your waypoint is shallower than your off gas ceiling.

The few times I haven't used this ascent profile, I have felt absolutely wrecked after the dives.

 

[Hatul]

Another way to look at the deeper safety stop is the point at which your ascent rate slows (a waypoint). The ascent rate below the waypoint is significantly faster than the ascent rate above the waypoint. The ascent rate to the surface after you've completed your shallow safety stop (another waypoint) should be even slower than the ascent rate you used to get there.

Assuming your deeper stop is above the point at which you begin to off gas (ceiling), there isn't a disadvantage to pausing for a minute before continuing your ascent at the slower rate. Half your average bottom depth should be a good rule of thumb that your waypoint is shallower than your off gas ceiling.

The few times I haven't used this ascent profile, I have felt absolutely wrecked after the dives.

That's consistent with the Uwatec Galileo algorithm, which uses a variable ascent rate, and Profile Dependent Intermediate Stops that are optimally chosen above the off gas ceiling. As long as I have NDL time I try to stay way below the shown ascent rate since most of the time I'm not trying to optimize my ascent time during shore diving.

 

[drbill]

Diving along the steep underwater profiles off Catalina and being a videographer, I have long employed multiple stops although not with precise planning about the depth at which I do them. I try to film critters to film at increasingly shallow depths as I ascend up slope. When doing square profile dives (as on a deep pinnacle, etc.) I plan on at least one deep stop as I inch up along the anchor line. Back when I was diving to max depths of 200 ft, I'd often use 3-4 stops even if I wasn't approaching NDL.

 

[dumpsterDiver]

Diving along the steep underwater profiles off Catalina and being a videographer, I have long employed multiple stops although not with precise planning about the depth at which I do them. I try to film critters to film at increasingly shallow depths as I ascend up slope. When doing square profile dives (as on a deep pinnacle, etc.) I plan on at least one deep stop as I inch up along the anchor line. Back when I was diving to max depths of 200 ft, I'd often use 3-4 stops even if I wasn't approaching NDL.

Hard to imagine a 200 ft dive that incorporates deep stops and does not result in just (alittle?) deco penalty accruing somewhere on the ascent..At least for my computer, anyway.

 

[tracydr]

I was certified NAUI in 1992 on Grand Cayman. We did this on every deep dive. Then I came back and started geting certs through other agencies and did not continue the practice. I cant tell any difference personally. Usually after back to back deep dives(100ft plus) Ill spend a little extra time at 15' but that is based on no sciemce whatsoever!

These studies were done with Doppler. Until you actually take a DCS hit, you usually won't be able to feel a difference.

 

[Searcaigh]

This is a very interesting and informative thread.

This is also very informative as well as this one

 

[racerx_]

This is a very interesting and informative thread.

This is also very informative as well as this one

This is getting more confusing! LOL