Valve Drill Sequence

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elan

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While doing valve drill with few people I found 3 different sequences are being used.

1. (as well shown on UTD video) right post shutdown, switching to the backup, right post opening, isolation shutdown and opening, left post shutdown, switching to primary, left post opening.

2. One person who recently finished Fundamentals was showing the same but he was switching back to the primary right after the right post is back.

3. One person who was doing Fundamentals some time ago was doing the isolation valve at the end, after left post is back.

So the question to the audience is which one is correct as of today and why ?

Thanks in advance.
 
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GUE is uniformly settled on #2 - switch back to primary after the right post drill.

As far as I know, UTD is settled on #1, which used to be the way GUE did it.

I haven't heard of the isolator-at-the-end method, though I imagine it doesn't really make much difference one way or the other.
 
i've seen both methods 1 and 2 ... haven't seen 3 yet though

my .02 is that i personally like method 1 since you actually breathe down both posts. for me it gives another tangible confirmation that the post is completely closed
 
I was taught the way outlined in #2 as well in my fundies class. I was also told that anyway you do it is correct. The purpose of the drill is to teach you muscle memory and get you good at manipulating valves.

IIRC, the reason they changed the DRILL to the sequence outlined in #2 was that it ensures you will always have a working regulator. First thing you do is check the backup for air delivery before shutting down R post. After manipulating R post, you switch back to primary, so you know your primary is working and turned on before shutting down the L post. I see the logic in this, but some people will still get the sequence wrong anyway, and shut down both posts on accident.

Tom
 
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i've seen both methods 1 and 2 ... haven't seen 3 yet though

my .02 is that i personally like method 1 since you actually breathe down both posts. for me it gives another tangible confirmation that the post is completely closed

Method #2 also involves purging the backup regulator after the left post is shutdown to verify it is shutdown all the way.

Tom
 
So the question to the audience is which one is correct as of today and why ?

There is no right or wrong unless you are referencing a particular agency's method.

I can do either #1 or #2 if you ask, I don't have a preference. #3 isn't necessarily "wrong", but it does not lead into failure management at all since after shutting down a post, if the bubbles don't stop we always shut down the isolator to preserve gas while we call in our buddy to fix the problem or tell us its unfixable.
 
I think its a typo. Shouldn't it be "right post shutdown, switching to the backup, RIGHT post opening"?

I was taught the way outlined in #2 as well in my fundies class. I was also told that anyway you do it is correct. The purpose of the drill is to teach you muscle memory and get you good at manipulating valves.

IIRC, the reason they changed the DRILL to the sequence outlined in #2 was that it ensures you will always have a working regulator. First thing you do is check the backup for air delivery before shutting down R post. After manipulating R post, you switch back to primary, so you know your primary is working and turned on before shutting down the L post. I see the logic in this, but some people will still get the sequence wrong anyway, and shut down both posts on accident.

Tom

Ok, understood, On UTD video they mention that before switching to the other reg one should purge it to make sure the air is on, but #2 looks more reliable.
 
There is no right or wrong unless you are referencing a particular agency's method.

I can do either #1 or #2 if you ask, I don't have a preference. #3 isn't necessarily "wrong", but it does not lead into failure management at all since after shutting down a post, if the bubbles don't stop we always shut down the isolator to preserve gas while we call in our buddy to fix the problem or tell us its unfixable.

So basically the idea is if bubbles start one closes the right post if they still go shutdown the isolator to make sure we have at least half reserve, then open the right, switch to primary and shutdown the left if bubbles stop, open the isolator, if they do not just leave the isolator closed. Is that a correct understanding ?
 
Ok, understood, On UTD video they mention that before switching to the other reg one should purge it to make sure the air is on, but #2 looks more reliable.

#1 is training your brain to associate what you are breathing with a particular knob

#2 is closer to a plausible failure management scenario (if you are breathing the left post you are unlikely to be shutting it down, although this is possible with multiple failures going on)

Do valve drills with a buddy so switching to a post turned off or shutting off all your gas isn't an issue. Modifying a drill to mitigate the risks of botching it is not the right way to approach safety, that's what your buddy is for.
 
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