Prebreathing regs

[cerich]

Puget sound really isn't that cold.

 

[gcbryan]

You're not going to die

 

[TSandM]

I've had my free-flow rite of passage. I would just prefer not to have to do it again.

So, what I'm gathering is that this is something mostly to worry about when air temperatures are well below freezing, or water temperatures are close to freezing, or both?

 

[Mr.X]

You're not going to die, although you might have some short dives. If it starts to freeze, you should have a procedure in place to mitigate the risk.

The easiest way to mitigate those risks is to watch other people do it. It's the best! Have a steaming hot dog while they dive. Watch boogers freeze into hard snot shards. Whatever you do - don't volunteer to drive your car onto thin ice.

If anything, having taught this kooky elective - it's an experience that everyone wants to say they have done, but rarely decide to repeat.

 

[cerich]

I've had my free-flow rite of passage. I would just prefer not to have to do it again.

So, what I'm gathering is that this is something mostly to worry about when air temperatures are well below freezing, or water temperatures are close to freezing, or both?

when air temps are close or below and water temp is below 40 or so.

Your Mk25 is not the most freeze resistant by far, but the right technique is more important than the most freeze resistant reg out there.

 

[djanni]

FWIW ...

Up heeya in (well I won't say where) the air temp drops well below freezing and the water temp will reach low 30s.

I use SP Mk16 1sts on Atomic seconds. I've pre-breathed (inhale only while watching the SPG needle) the regs, with no subsquent problems when the air temp was in the teens and the water temp in upper 30s/low 40s. I also double check the valve just before donning the rig. Most of the problems I've ever encountered have been in that "zone" where all of me is wet but the tank valve/reg is now out of the water because I am talking to the skipper of boat who is hauling the traps I cut free.

Wow! I've gotten a chill just reading this. I humbly submit that you have to be the most dedicated diver I've come across so far. I love to dive but most likely, I'll never dive north of the Mason-Dixon line. My greatest respect goes to you.

 

[Kwbyron]

Does it get that cold here in the sound? I know it dropped below freezing every now and then, but I was under the impression that the water temp was fairly constant, not really getting below 45 or above 55. So if the risk is the reg icing up from watervapor in our breaths, wouldn't we be able to just submerge the reg for a minute while bobing on the surface? Seems not only the warmer water, but salt would melt it off rather quickly..... i dono though...

 

[TSandM]

Well, I did dive when it was 25 degrees this winter. So I thank you for the advice about avoiding breathing off the reg when the first stage is wet but not immersed.

 

[Snowbear]

You're going to die. But none of us can tell you when that will be.
Freezing your new regs shouldn't be any more of a problem than freezing your old Apeks was.

Up here, in winter I avoid "pre-breathing" my regs before entering the water. I have not died from it yet, though once or twice I have had to reach back and turn on my tank valve after I submerged :11:

No-one I know who does pre-breathe their regs has died yet either... though they sometimes delay the dive while we submerge their rig to thaw out the first stage so we can turn the valve back on without it freezeflowing again

I seriously doubt you should have this problem in Puget Sound, so keep doing what you're doing and don't worry about what the SBers from Georgia do

 

[lamont]

i'd prebreathe. the water temp never gets below 45F and the air is rarely below 32F around here, and if it doesn't freeflow while you're still on the surface it isn't going to spontaneously freeze up while you're diving around here.

typically we do our prebreathing before bubble checks as well, and the bubble check involves dunking your first stage below the surface of the water, which should warm it up if its freezing...