Hypoxia

Duncan Price

Was diving a popular inland commercial dive site yesterday evening with my significant other who was on open circuit. We were just returning to the shore when we became separated. I was at 6-8m. Did a 360 to look for her (she was above me on the surface). Then another, so also headed for the surface. Met topside and it wasn't until I stuck my head back in the water to surface swim back to shore that I heard the alarms on my Oxyguages going off. There was 17% O2 in the loop. I'd kepth my mouthpiece in all the time.

Basically during the last few minutes I'd been concerned with other things and had not monitored my ppO2 during search and ascent.

No noticable ill effects. But...

Duncan

Mdemon

Glad you spotted it and got out OK Duncan.

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"Once the agenda-monkeys and perfect-worlders have moved on, perhaps we can do some diving?"

ROB DAVIE

Glad for both of you that it worked out without harm. It's a note of caution to us all!

Rob

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[SIZE=2]"CC Rebreathers will become a viable part of tech diving [U]WHEN PIGS FLY[/U]!!"--GI3[/SIZE]

Mark Chase

Thats the trouble with CCR, no matter how many hours you have on the thing a laps of concentration can have serious side efects. I dont care how much of a dive god people claim to be we all suffer from these distractions / lapses.

Thanks for the reminder.

Hey,,, I have a great idea. How bout putting an electronic system in the unit that monitors your PP02 and automaticly injects some 02 to maintain a set point pre set by your self.??


ATB

Mark Chase

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Is it supposed to make that noise ?

I took my unit to the dive shop and demanded they bolt on every thing that would fit.

Join my elite diving teem and get a Tshirt

"Doing It Chasey"Hammerhead Eccr Advanced Diving System

Beanie

agreed
fine unless your on the wrong set point

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UWSojourner

True, but it's hard to be on a set point much "wronger" than 17%.

Drmike

Easily done mate (too easily!)

On an 80m dive I was busy and not really keeping an eye on the HUD or checking my handset enough. As luck would have it my unit decided to switch itself off. Luckily I was at 80m at the time and not ascending. I didn't notice the HUD light go out. When I did I immediately gave a little squirt of O2 and then checked the secondary. Fortunately as I was at const. depth it hadn't dropped much and it was still over 1.0. I switched the unit back on and it seemed ok.

However - being the twit that I am I didn't learn from this and at the end of the dive as I was ascending up the side of the wreck to the upline there was a short time that the unit switched off again. When I realized I checked the display and it was 0.7ish.

Obviously nowhere near life threatening - but it did mess up my deco schedule somewhat and brought home the dangers of not monitoring enough especially on ascents.

I think it was a good wake up call. I was getting complacent with the frequency of checking my handset/hud. (I find I have to still make a conscious effort to 'look' at the hud, even though its in view all the time)


The reason the unit kept switching off was the magnet on the on/off reed switch was corroded and it was loosing contact.

Duncan Price

My significant other and dive buddy from this dive is now reading "Mastering Rebreathers" - I did brief her before the dive that I would be unable to do rapid descents/ascents and also the "lost buddy" protocol. We've now been through rebreather operations in a lot more detail and she's now more aware of issues which might arise. We should have done this before the dive but it is a lot to take in but it would probably have helped. Notwithstanding the need to check your ppO2 regularly, this incident also highlights the problems diving with someone who is not familiar with your rig.

caveseeker7

You're a real trooper, Duncan, you came through for me again.
Nice little reminder, thanks.

That's something I've been thinking about of late, folks.
With a regular dive buddy some in-depth knowledge of rebreathers and the particular unit used is the way to go. But how much do you guys and gals tell occasonal buddies (who isn't intrested in reading a textbook) or worse, a dive master selected stranger? Do Madmole's and APD's lists suffice? Do you tell them more? Less? To keep away 10 ft. at all times as long as you're concious?

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Stefan



"Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media,
which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.'!"

narked at 90

glad it worked out ok duncan sorry i couldnt make it the other day what with a cold and a broken breather, this is a worry i have on the surface as in bright day light i cant see my diplays, so when i arrive to the surface i purge my loop and keep purging regular until i come off loop.

i tend not to tell buddys to much on the first dive apart from the very basics.. dont remove my dsv with out closing it and how to switch my oc/dsv them give me a slap if im looking like im passing out, if they become regular they get the hole lot but it try not to over do it to start

kind regards john routley

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