Valves "full open" or not?

[lamont]

That said I always thought it was one of those things you just heard about. But I actually saw a DM turn off a persons air when he could not get the valve to move when he checked it before the guy went in the water. Lots of people on the boat he was busy and just made a mistake. Luckily the guy's buddy caught it. I always tell the DM my air is on and don't touch my gear.

On charter boats you'll sometimes get the surface support habitually turning people's air on before they jump in. Its probably a good idea on those dives to make sure that you breathe your long hose enough breaths to ensure your valve is on enough for surface breathing, and then do a quick valve check at the surface or right upon descending.

Haven't seen this ever for divers in doubles though...

 

[Dive-aholic]

Haven't seen this ever for divers in doubles though...

Impossible to do it for divers in sidemount since our valves are in our arm pits...

 

[lamont]

Impossible to do it for divers in sidemount since our valves are in our arm pits...

finally! a reason for me to dive sidemount! =)

 

[theITdiver]

I brought this question up at the LDS last week. they said they recommend turning a half turn back after opening because leaving the valve full-open compresses the teflon (or nylon) seal in the valve. the longer it is compressed, the less life you get from it. by closing the valve the half turn, you relieve the compression from that seal.

 

[Dive-aholic]

Sure, if you jam open the valve, you might compress the teflon seal in it, but if you just open it so that it comes to a stop you won't be compressing anything. I open my valves all the way and I service all my own valves and haven't had any issues. Apparently someone at your LDS likes to manhandle the valves...

 

[wreckchick]

To compromise between the old-skool 1/4-1/2 turn back people and my personal "all the way on" beliefs, I've gone to teaching "all the way on and a millimeter back." This way you barely have to touch the valve to realize it's on but it's never cranked open.

Rachel

 

[GDI]

To compromise between the old-skool 1/4-1/2 turn back people and my personal "all the way on" beliefs, I've gone to teaching "all the way on and a millimeter back." This way you barely have to touch the valve to realize it's on but it's never cranked open.

Rachel

AND if the valve gets bumped it reduces the risk of it jamming open

 

[Ann Marie]

I'm curious... when your student goes to jump off the back of the boat and you're checking their valve and it doesn't turn, how do you know for certain that it isn't jammed shut, rather than open all the way?

Sorry, haven't read this thread in a few days.

I guess I should have clarified my answer just a little as I went with the OPs question, "full open or not?".

I do teach my students to back off a little but not near the 1/4 turn that I was taught. I don't check the valves, I don't touch a students gear unless it is to help them don it. If something isn't routed correctly, I let them know and they can fix it. We do buddy checks which include inflating BCs, breathing off each regulator a few times while looking at the SPG to make sure that the air pressure remains constant (as well as other steps in the buddy check). I tell my students that I don't like people touching my equipment and that I am ultimately responsible for how it is set up since I am the one using it. I try to teach personal responsibility not babysitting diving.

I also realize that I am posting in a tech forum, my original post was to the poster that was asking about the PADI standard.

 

[SlowRain]

In regards to tech diving....fully opened and back maybe an 8th of a turn, simply because in the confusion of something gone wrong, I don't want to end up having myself or someone else wasting the time turning the valve the wrong way.

If it costs me having the valves overhauled more often....who cares.

 

[fishyangel]

I just took PADI OW and the book said that it was not necessary to turn the 1/4 turn back but to expect that many people would tell you to do so, since it was standard practice for so long.