Deep Stops Increases DCS

[boulderjohn]

Yup, the RGBM algorithm is promoted by Naui tech. However, it is not the only algorithm used by Naui tech divers...Many algorithms are discussed, and certainly the pro's, cons and limitations of each are discussed as well. The reality is that unless you can teach tech courses in a location(or on a vessel) where a 3hr SIT is attainable, you are better off jumping to Buhlmann (unless of course you feel the need to spend a couple hundred bucks on Gap software) as the software is readily available and relatively cheap, and the Multi level dive computers that are capable of planning decompression dives generally support that algorithm(as well as VPM and now Liquivision supports RGBM on the Xeo).

RGBM is not the only answer, although neither is Buhlmann.

I am not sure of this, but doesn't NAUI also teach the use of deep stops in recreational diving as well?

 

[Divetech99]

for what it's worth I've done a ton of VPM diving and have never been bent. but there is a growing number of divers that are having issues with it
i'm with GUE these days on deep stops. slow your ascent but making it a 'stop' is probably not the way to go.

Liteheaded, what is the new GUE standards for ascent rates and deep stops?

Btw, great videos on your cave dives.

 

[tomfcrist]

I am not sure of this, but doesn't NAUI also teach the use of deep stops in recreational diving as well?

The direct answer is that NAUI instructors are not required to teach deep stops, but it is recommended. Section 2 of the S&P:

Dive Tables.​

NAUI endorses the use of U.S. Navy-based dive tables using NAUI’s reduced time limits, RGBM-based tables, the Canadian Department of Defense, Civil Institute of Environmental Medicine (DCIEM) dive tables, and Bühlmann tables. It is recommended that following dives in excess of 40feet (12 m), divers make a two to three minute stop (with two and one-half minutes being optimum) at a depth that is half that of the deepest depth reached during the dive and make a precautionary stop in the 10-20 feet (3-6 m) zone for one minute before returning to the surface. The precautionary stop time maybe considered “neutral” time- not counted as either dive time or​

surface interval time.

 

[LiteHedded]

Liteheaded, what is the new GUE standards for ascent rates and deep stops?

Btw, great videos on your cave dives.

it basically amounts to a slower ascent rate when you get to 'deep stops' territory. pauses rather than stops
beyond this you can take tech 1 and 2 to find out

 

[PfcAJ]

How did Naui come up with a 2:30 stop time at half of max depth as "optimum"? What's that based on?

 

[tomfcrist]

How did Naui come up with a 2:30 stop time at half of max depth as "optimum"? What's that based on?

I can't seem to find that answer in writing...so don't quote me on this, but if I recall that recommendation came from Dr Peter Bennett.

 

[cerich]

I can't seem to find that answer in writing...so don't quote me on this, but if I recall that recommendation came about based on research done by Dr Peter Bennett.

It came about when Bruce was on the BOD, he has done some work on deco....

Dr. Bruce Wienke - Vanguard Diving & Exploration

 

[tomfcrist]

Cerich, are you referring to deep stops being referenced in the S&P, or the change in duration that came in 2008ish

 

[ajduplessis]

How did Naui come up with a 2:30 stop time at half of max depth as "optimum"? What's that based on?

Nothing is optimum..... My understanding

Half the max depth = half the total pressure. The 2 or 2:30min is generally thought to be the time required to fully circulate the enitre respiratory system and thereby getting rid of most of the microbulles within the systems during that window.

Example (30m max depth):
1st deep stop @ half the total pressure (30m/2=15m).
Second stop would then be half the remaining pressure (15m/2=7.5m) The pressure at the second stop is 1.75 ata where the surface contribute 1ata pressure. Because the difference is less than half they add a precautionary stop at 3-6m as "saftey".

 

[cerich]

He had his hand (as did Tim) in both.

Cerich, are you referring to deep stops being referenced in the S&P, or the change in duration that came in 2008ish