PADI Screws Up With Nitrox Publication Again

[DandyDon]

(Please correct me if I'm wrong here, before I contact them about an immediate recall need.)

I convinced my buddy that he needed to get Nitrox certified - in part, to dive with me on two trips we plan to do together, and by the time he signed up, the course had gone up $25 to offset the cost of the new VCR video now included.

We watched the flick together, and it's probably a good idea - in helping introduce a recreational diver to the somewhat technical course. But in the scene illustrating how a diver verfies and marks the tank with the O2 percentage and MOD, it shows: :dontgetit 29% / 110 feet. hyeah20:

Unless it's me who screwed up here, the MOD for 32% is 111 feet, and the MOD for 29% is 126.

thanks, don
:help:

 

[theskull]

Dandy,

Your math is absolutely correct. However, that does not mean there is anything wrong with a diver using limits that are more conservative.

Or perhaps even more lazy. . . often when I ask for 32% and get 29% I will just mark the tank EAN 29/MOD 110 . . . because I only planned 110 ft. dives anyway and I KNOW that EAN 29 is safe to that depth. Of course, I will set my computer to 29% and dive the correct tables!

I think you're making too much of it. And if we wanted to do the same, we could point out that not everyone uses 1.4 as a limiting factor, especially for cold water or repetitive dives.

theskull

 

[MSP Rescue Diver]

Did it say what PPO they were using? Using a PPO slightly lower than 1.3 would get the results shown in the video.

Marc

 

[chrpai]

New videotape? My class had a tape 2 1/2 years ago.

 

[DandyDon]

Did it say what PPO they were using? Using a PPO slightly lower than 1.3 would get the results shown in the video.

Marc

PADI teaches using 1.4, as compared to NOAA and US Navy using 1.6 - which Paid teaches as a Contingency depth. Padi also teaches in the book and course to calculate the MOD based on the O2 content, so this simply strikes me as an incongruent mistake. While a diver might chose more conservatism after the diver has the basics down pat, teaching one approach but illustrating something different seems odd.

New videotape? My class had a tape 2 1/2 years ago.

Was that PADI Nitrox course? I took one 1-1/2 years ago, and it wasn't included. Perhaps it was an option? It was not included with this small LDS in the recent past, but is now, or - maybe the LDS recently decided to require it in their courses? All interesting points.

But back to this apparent mis-illustration...??

 

[Damselfish]

Did PADI Nitrox 4 years ago, and the first thing we did was watch a video. Wasn't a video to keep though.

 

[roakey]

I got a video to keep back in '98 when I took PADI Nitrox. The copyright on the tape label is 1996.

Roak

 

[DepartureDiver]

Yes, PADI teaches a 1.4 as max and I believe a 1.3 in general ... and as everryone as pointed out, your math for a 1.4 MOD was right on. While PADI has always done this, I think the trend in general is to pull to ppO back these days ... which I have always agreed with. I have never advocated for a 1.6 bottom mix. I think it is fine to let a diver know that a 1.6 is acceptable in case they go deeper, but for CO2 reasons and others, I think a 1.3 to 1.4 is a better max in general. Of course there are always exceptions.

 

[JohnF]

Dandy,

I think you're making too much of it. And if we wanted to do the same, we could point out that not everyone uses 1.4 as a limiting factor, especially for cold water or repetitive dives.

theskull

You're right that it probably doesn't matter to someone who's familiar with Nitrox, but since this is in a learning context, shouldn't there be a little more care given to consistency? The idea of the course is to help nitrox newbies understand it, and throwing errors, albeit erring to the safe side, at them in the course material isn't particularly conducive to easy comprehension. I think the KISS principle applies here.

JohnF

 

[Dive Source]

TDI uses 1.6 to calculate/ID the MOD with 1.4 being used for planning the dive.

IMO using a PO2 of 1.4 to mark MOD leaves the student with room for interpretation while underwater since they will be thinking "oh my MOD is based on 1.4 but it's ok if I go a little deeper as I have a contingincy". - But that 1.6 max depth number won't be right in their face.

Using 1.6 as a max screams do not go past this depth - stay away.

I guess it's a matter of perception but I hate to see people using different standards for basic terminology as it leads to confusion.

I believe IANTD, NAUI and GUE use 1.6 as MOD/tank marking with working PO2 of 1.4 ( please correct me if I am wrong here as I want to know) - Why does PADI have to be different?