Exceeding NDL on an al80?

[Kharon]

I think most folks with a lot of dive experience, basically "comfortable in the water", can easily get into some level of mandatory deco at normal recreational depths with an al80. For resort, vacation, or most newer divers I think an al80 will keep them out of deco.

Kind of chauvonistic and a bit dangerous advice. Anyone can get into deco with an 80cf if they are being still, simply observing in a single spot or small area and not continually cruising along. Also, for less experienced divers on a slope or a wall they could easily find themselves much deeper than they expect for longer than they want.

 

[RayfromTX]

Smaller divers tend to sip air and are more likely to be NDL limited. I know women that could be in deco in the first 800 psi on an AL80 on a liberal computer algorithm. Context counts.

 

[scubadada]

Smaller divers tend to sip air and are more likely to be NDL limited. I know women that could be in deco in the first 800 psi on an AL80 on a liberal computer algorithm. Context counts.

Anybody with a reasonable RMV could fairly easily be NDL limited on air using an AL80. It would be a little harder on nitrox.

As an example, if I descended directly to 100 feet, stayed at that depth for a little under 19 minutes (DSAT NDL for air), and then made a normal ascent and safety stop, I would surface with a little under 1700 psi. On the same dive with 32%, where the DSAT NDL is 30 min, I would surface with just a little over 1000 psi. You would not do this dive on 36%, as pO2 is 1.45, the MOD is 95 feet.

Anybody who knows their RMV can do similar calculations

 

[Jack Hammer]

Kind of chauvonistic and a bit dangerous advice.

You should report this.

 

[nquinn]

For those that do get close to your NDL limits, I'm curious how conservative people are when decide to start ascending. 1, 2, 3, 4, 5min of NDL left?

 

[BRT]

For those that do get close to your NDL limits, I'm curious how conservative people are when decide to start ascending. 1, 2, 3, 4, 5min of NDL left?

A younger man with my name used often ride the computer all the way up at the 1 minute marks. I don't unless there is really something to be gained.

 

[CWK]

I think of ceilings as having 2 parts, a true deco ceiling and a safety ceiling. Think of a tec diver doing a deco dive that exceeds the M-value with GF on xx/85. The true deco ceiling gets him from xx/M-value plus to xx/100. The safety ceiling takes him from xx/100 to xx/85.

On recreational dives, I regularly have a safety ceiling but as I do not exceed the M-value, I do not have a true deco ceiling. I could probably exceed M-value on a single Al80 but I choose not to.

 

[CWK]

BTW, I dive with 2 computers. My Shearwater is set to 50/80 and regularly shows a ceiling. My Suunto is set to 0 which is similar to xx/95. I don’t exceed the NDL shown in my Suunto, so I never have a true deco ceiling on recreational dives.

 

[KeithG]

For those that do get close to your NDL limits, I'm curious how conservative people are when decide to start ascending. 1, 2, 3, 4, 5min of NDL left?

"Do" or "can"? This thread is about "can". The topic of "do" likely warrants a new thread about riding your computer.

 

[CWK]

NDLs shown on computers do not exactly equate to M-values. Does anyone exceed M-values on a single Al80?