OK to Bounce Dive to 220 Fsw as...

[OneBoatNut]

I was sitting at a table of beginner and newly acquired advanced level divers (they were rewarded their advanced cards at dinner) the instructor told one of the divers it would be fine to drop down to 220 and come right back up…

What are the issues here especially if the diver is pretty overweight and out of shape…

 

[Michael_Lambert]

Like any dive you need to measure out your risk and way them and decide is it worth it.

At best diving a Po2 of 1.6 ( 21%) you would still be limited to 218 feet. So to awnser your question 220 feet okay... NO!

 

[Rainer]

Sounds awesome. What could go wrong?

 

[OneBoatNut]

I understand partial pressure isn't really the issue, since hyperbaric chambers help people heal and they are at 2.0

My question was geared toward narcosis and ascent rates
and that they would be making a fast decent to hit 220.

The instructor that mentioned this is an SSI instructor and I see problems with anyone diving outside their bounds just to hit a depth mark. Narcosis would be an increased risk with the rapid decent and ascent –

More thoughts?

 

[M_Bipartitus]

You would likely be fine "drop(ing) down to 220" coming back up may not be so easy.

 

[HowardE]

I understand partial pressure isn't really the issue, since hyperbaric chambers help people heal and they are at 2.0

My question was geared toward narcosis and ascent rates
and that they would be making a fast decent to hit 220.

The instructor that mentioned this is an SSI instructor and I see problems with anyone diving outside their bounds just to hit a depth mark. Narcosis would be an increased risk with the rapid decent and ascent –

More thoughts?

Isn't "Advanced Diver" still a recreational certification? Wouldn't the accepted depth limit for recreational diving still be 130' ??

Even a bounce dive to 220 would require decompression. This seems a tad bit beyond the level for "advanced diver"??

 

[OneBoatNut]

Howard I agree with you, I said the diver would need to check for a stop, deco or otherwise, since the statement didn't include his dive record for the day etc.
I was ridiculed by the dive instructor as he stated he was right and it is fine to bounce.
I stopped talking and said wow, and then I asked "are you a tech diver instructor?" the answer was "no"

 

[Blackwood]

What would be the point?

Unless I have a crucial task like clearing an anchor or something like that, I don't ever see myself planning a bounce dive. I like to, you know... dive, not just descend and ascend.

 

[boomx5]

Howard I agree with you, I said the diver would need to check for a stop, deco or otherwise, since the statement didn't include his dive record for the day etc.
I was ridiculed by the dive instructor as he stated he was right and it is fine to bounce.
I stopped talking and said wow, and then I asked "are you a tech diver instructor?" the answer was "no"

Tell him there's a real friendly place called Scubaboard.com and that he should join us for a discussion on the subject.

 

[gcbryan]

I was sitting at a table of beginner and newly acquired advanced level divers (they were rewarded their advanced cards at dinner) the instructor told one of the divers it would be fine to drop down to 220 and come right back up…

What are the issues here especially if the diver is pretty overweight and out of shape…

Are you sure you understood the context of this discussion?

Was the instructor saying this is no big deal perhaps you should try it?

Was he just using this theoretical scenario to discuss PPO2 and limited N2 loading?

I have a hard time believing that he was suggesting this as something appropriate for the students at that table.

By the way, being over weight and out of shape would be the least of my concerns with this scenario.