Mares puck pro and deco question

[BoltSnap]

If you missed a deco obligation you would not be locked out, but would put the computer into gauge mode.

Computer going into a gauge mode for the reminder of the day is defined as "lockout" in this context.

 

[Manatee Diver]

It must be noted that the Mares, Cressi and Suunto computers that are based on the RGBM deco algorithm get real uptight when the diver doesn't stop for the required deco stop or the "required" safety stop. These computers have two types of "safety" stops, "optional" and "required" safety stops in addition to the required "deco" stop. If you violate either of the "required" safety stop or the required "deco" stop, you get locked out for the next 24 hours (I think 24 hours or perhaps more).

I've blown off Suunto mandatory safety stops a couple of times, all it does is issue you a little warning on the dive screen. Also if you go in the log you will see the safety stop ceiling error along with a tissue warning. But it doesn't lock you out that is only reserved for skipping a deco stop.

 

[BoltSnap]

I've blown off Suunto mandatory safety stops a couple of times, all it does is issue you a little warning on the dive screen. Also if you go in the log you will see the safety stop ceiling error along with a tissue warning. But it doesn't lock you out that is only reserved for skipping a deco stop.

You are probably right, I don't have access to the Suunto manuals now but I'll check again when I have access to them later. It probably just put severe limits on your NDL's for the following dives when you ignore the "required" safety stops but no lock you out.

 

[dberry]

Its interesting that the total is 8 minutes wonder if that is just a coincidence same total as padi RDP recommends. Ascent rate with padi is 60fpm vs the mares 40fpm

Is this correct? I thought PADI teaches 30 fpm for ascents; I'm not sure if they still recommend 60 fpm for ascents from greater depths (still in Rec, of course) and then 30fpm for the more shallow ascents.

 

[Jiminy]

Is this correct? I thought PADI teaches 30 fpm for ascents; I'm not sure if they still recommend 60 fpm for ascents from greater depths (still in Rec, of course) and then 30fpm for the more shallow ascents.

I was looking at Padi RDP Ver 1.2 (Rev. 02/03) Interested to know if this was revised

 

[rjack321]

I was looking at Padi RDP Ver 1.2 (Rev. 02/03) Interested to know if this was revised

PADI has only recommended a max 60fpm for a long long time (30+ yrs)
They suggest 30fpm but the tables have not been retested and validated with that rate. So they haven't been reprinted with a 30fpm "max" mostly for litigation reasons.

 

[dberry]

Interesting... So the PADI OW book recommends 30, not 60, but the tables (DSAT?) are based on the faster rate?
I just checked, and the Navy Dive Manual (2008, rev6) says to use 30fpm for non-emergency ascents, and I assume their tables are based on 30fpm ascent.

The dive computers I've used (Perdix and Oceanic) also trigger a warning at an ascent rate above 30fpm. However, the warning (Perdix) becomes much more insistent above 60fpm. The Perdix manual says deco calcs are based on 33fpm (10mpm) ascent.

It's surprising that PADI hasn't the max rate changed everywhere.

 

[Jiminy]

Interesting... So the PADI OW book recommends 30, not 60, but the tables (DSAT?) are based on the faster rate?
I just checked, and the Navy Dive Manual (2008, rev6) says to use 30fpm for non-emergency ascents, and I assume their tables are based on 30fpm ascent.

The dive computers I've used (Perdix and Oceanic) also trigger a warning at an ascent rate above 30fpm. However, the warning (Perdix) becomes much more insistent above 60fpm. The Perdix manual says deco calcs are based on 33fpm (10mpm) ascent.

It's surprising that PADI hasn't the max rate changed everywhere.

Its just listed as a general rule on the back of the RDP. That is the problem with general rules there is no context.
60 max is probably better for most people in a OOA emergency and 30 max has a safety margin built in for general diving.i would guess

 

[dmaziuk]

60 max is probably better for most people in a OOA emergency and 30 max has a safety margin built in for general diving.i would guess

There is an equation to calculate gas (un-)loading during ascent. It needs ascent rate. When your computer calculates the NDL, it uses that formula and makes an assumption about your ascent rate. I expect most computers that do it that way assume 33 fpm. If you go faster than that, the pre-computed NDL may be off, as in you didn't "unload" as much gas during ascent as the computer expected. You may end up blowing a "mandatory stop" and locking yourself out for a day. (It's unlikely you'd actually get clinical DCS in this scenario, but not impossible.)

 

[Jiminy]

There is an equation to calculate gas (un-)loading during ascent. It needs ascent rate. When your computer calculates the NDL, it uses that formula and makes an assumption about your ascent rate. I expect most computers that do it that way assume 33 fpm. If you go faster than that, the pre-computed NDL may be off, as in you didn't "unload" as much gas during ascent as the computer expected. You may end up blowing a "mandatory stop" and locking yourself out for a day. (It's unlikely you'd actually get clinical DCS in this scenario, but not impossible.)

That is an interesting thought I wonder how much you unload on 100ft vs a 40ft ascent...I imagine the deeper the dive the higher the risk?