Found a near-miss on youtube

[iztok]

kaerius, my title is correct. But if this is correct answer then "correct" answer is simply wrong.

 

[kaerius]

I had a look through my DM exam booklets and it seems that question must've been on the IDC rather than the DM course. The IDC exams were a bit of a mixture of official exams and exams written by the course directors, it's quite possible that this was a mistake by a course director, they are afterall human, but perhaps it's simply a prudent industry praxis, due to the fact that much blending is done with air and pure oxygen. It would afterall be bad to take a nitrox tank that isn't oxygen cleaned to be filled, if the filling station ends up being one that blends directly, this being perhaps the most common way to produce nitrox.

 

[iztok]

Kaerius, think about it. If filling station does partial blending then their air has to be O2 compatible. Thus filling tanks with that air will not contaminate it.

 

[dumpsterDiver]

Kaerius, think about it. If filling station does partial blending then their air has to be O2 compatible. Thus filling tanks with that air will not contaminate it.

I just checked the PADI manual. thinking for yourself was not mentioned. I think the prudent thing is to destroy the tank and shut the dive shop down.

 

[ff1diver]

Amen burna!
I am going to feel sorry for the poor diver who is going to be behind him for the wreck penetration class...lol

 

[Thalassamania]

I just remember old questions from the tests for DM and IDC, where the correct answer what to do if you accidentally fill a nitrox tank with regular air is to have it oxygen cleaned. It may just be a PADI thing.

Might be something to remember for you iztok if your forum title is correct and you're with PADI.

I remember because I got it wrong on the test, my gut reaction was also that it should be fine.

Regardless of whose test, that answer is WRONG!

Amen burna!
I am going to feel sorry for the poor diver who is going to be behind him for the wreck penetration class...lol

The diver in the video is over weighted, has not concept of trim and thinks that he is riding a bicycle.

 

[carrielsal]

Regardless of whose test, that answer is WRONG!
The diver in the video is over weighted, has not concept of trim and thinks that he is riding a bicycle.

How can you tell he is overweighted?

 

[Thalassamania]

Feet down, constantly kicking, no progress up.

 

[sydney-diver]

I just remember old questions from the tests for DM and IDC, where the correct answer what to do if you accidentally fill a nitrox tank with regular air is to have it oxygen cleaned. It may just be a PADI thing.

Might be something to remember for you iztok if your forum title is correct and you're with PADI.

I remember because I got it wrong on the test, my gut reaction was also that it should be fine.

I just dug out my PADI manual. It says

"Enriched air cylindars should never be filled from a station that does not handle enriched air" pg27

"If you ever need to use air in an enriched air cylindar, take it to an enriched air fill centre. The fill is treated as enriched air in all respects, including marking it EANx21, analyzing the contents and completing all records. If an enriched air cylindar that has been prepared for oxygen service (for partial pressure filling) is accidentially filled from a conventional air source, it must be serviced and cleaned by someone qualified to service enriched air equipment before being exposed to more than 40% oxygen again." pg28

(emphasis by PADI).

So yes you would get this question wrong if doing a PADI exam (and depending on the wording, i.e. you don't have to get it cleaned but you cannot get a partial blend fill until you do).

 

[fisheater]

How can you tell he is overweighted?

He's so negatively buoyant that he has to keep kicking while at an angle (above horizontal) just to keep from sinking.