Nitrox for the PS diver

[NorthWoodsDiver]

as a huge proponent of Nitrox I wanted to here the argument about using it in a public safety divers tanks.

break cost away from the scenario, as everyone knows it costs more. but increased bottom time or probably more importantly shorter surface intervals seems to make nitrox really make alot of sense in the PSD world.

Sure you need a source and an analyzer and I suppose it increases training requirements but...

 

[tc]

In California CalOSHA still applies to PS diving. No problem using nitrox as long as you have a chamber at the dive site.

 

[mntdiver]

 

[1_T_Submariner]

I would think speed of getting in the water would be more important than bottom time.

Also in a lot of locations the diving would not be that deep to worry about it or deep enough that Ox Tox could be more of a worry.

I could be wrong but, just seems like a complication they would not want to add.

Maybe good to have a few tanks around for a longer search for something I guess when there would be more time to plan the profiles etc....

 

[Gary D.]

Simple answer; Higher % Nitrox takes more dive planning than 21% does. In the PSD world it isn’t a problem for RECOVERY teams. But it could be deadly for RESCUE teams who DO NOT have the option of planning a dive.

Long bottom times should not be done in PSD. Shorter bottom times with more dives should be the norm.

Gary D.

 

[Anti-Hero]

In California CalOSHA still applies to PS diving. No problem using nitrox as long as you have a chamber at the dive site.

Why would you need a chamber at the dive site for Nitrox? We don't use Nitrox, but I've never heard of any Cal OSHA requirements regarding it's use.

I just did a *very* cursory look on the OSHA site and didn't find any reference to PSD or using Nitrox.

 

[tc]

California Code of Regulations, Title 8, Section 6061. Specific Operations Procedures.

And please note- I think it's ridiculous too, but there it is.

 

[DA Aquamaster]

I agree with the distinction between rescue and recovery as with the former time is critical and you never know quite what you are going to get. With the latter greater planning and preparation should occur as the time is available.

On the other hand, how many PSD divers are really qualified to dive below the 110ft (PPO of 1.4) or 130 ft (PPO of 1.6) MOD of 32% or the 120 ft or 140 ft MOD's of 30%? How about the 140 ft or 170 ft MOD's of 26%? At some point there is a depth below which the team's divers are not or should not be allowed to go due to lack of training/skills/experience, narcosis or very short NDL's and that depth then becomes the determining factor for what mix is put in the tank.

I understand not wanting to have PSD's engage in deco diving, but let's say you are attempting a search and rescue in 110 ft of water. Your NDL with air is 15 minutes while you have 25 minutes with 32% offering significantly more bottom time or alternatively greater safety on the shorter dive and/or a shorter surface interval between subsequent dives.

From that perspective, Nitrox is just another potential tool in the tool box.

 

[DA Aquamaster]

California Code of Regulations, Title 8, Section 6061. Specific Operations Procedures.

And please note- I think it's ridiculous too, but there it is.

The regs make perfect sense in terms of "mixed gas" if it is defined as mixes such as heliox or trimix, but the intent clearly is directed at deep diving, not dives shallower than 100'.

I'd be interested in a legal opinion as to whether "mixed gas" applies to nitrox that is by definition intended for shallow water use - unlike mixed gases utilizing helium. I supect the regs and underlying statute pre date the common use of nitrox mixes and that nitrox has just been swept up in the "mixed gas" terminology that used to be synonymous with helium based mixes with no regulatory intent to ever include nitrox in this category.

Then again, it is the PRK and getting them to unforbid anything they've already forbid, intentional or otherwise, is a daunting task.

 

[Gary D.]

My argument is if you’re on a RECOVERY team go ahead and use higher percentages. But to eliminate the chance of someone making a mistake in the confusion of a RESCUE, NO mixes over 21% should be used on a RESCUE team period.

Many times we go from one call to another. We fill off the compressor trailer or directly off the trucks. Way to easy to get mixes fubared and tanks confused.

On the deep dives Rescue becomes Recovery much faster than at shallow depths. If it’s beyond what 21% can do it’s going to be a Recovery and not many searches should be done at the deeper depths unless you have a good target.

Gary D.