stretchthepenn
Contributor
A story from today's dives, for your edification and amusement.
My dive buddy and I primarily dive SM, and today, we dived a quarry to practice our AN/DP skills -- swim a route, ditch-and-don two deco tanks, blow a bag, practice two NOTOX gas switches on the way up. Not a huge deal...we were only in 20-40' of water and running drills we've done over and over again, but these are perishable skills, and we need to knock some of the rust off after a regrettably dive-light winter. And I was using new deco regs, so I needed to learn their quirks.
The first dive was chill. The second got exciting.
On the second dive, everything up to the second simulated deco hang went fine. We swam our route, completed skills along the way, blew our bags, and ascended to the target depth of 30'. There, we made our initial NOTOX switches, chilled out for 2 minutes, prepped the next switch while waiting, and then ascended to 20' for the second gas switch.
Everything went well until about a minute into the second hang, when I heard and felt a nearly deafening BANG and the water around me turned white. And, when I tried to inhale, nothing came in.
You guessed it...my second stage had popped off the hose, and a loose hose was whipping around, venting NOx50 like mad.
I kept my head. Mostly. I felt dazed from the blast, but reason quickly returned. I pulled the loose second from my mouth and replaced it with my necklace reg. In doing so, I lost my downline in the bubble storm and must've started sucking air like mad because I started to ascend, and went up faster -- much faster -- than I wanted to. Happily, I exhaled constantly so I didn't embolize, and I was right next to a buoy line, so I used it to arrest my upward motion at 10'. I then vented my bladder and drysuit, closed the offending tank, breathed air while I generally got my crap reorganized, and surfaced with my buddy.
So, basically, I experienced a lost-gas scenario/OOA during (simulated) accelerated deco and dealt with it successfully. But I could've done better.
Lessons:
1. Tighten down the second stage connections, especially when diving a new reg.
2. Chill, yo. Breathe evenly, especially when there's a problem.
3. Keep hold of my personal downline. If I exhale enough to sink and/or I emergency-vent, I can return to my target depth and avoid bending myself.
4. Air is a good choice, but once the situation is handled, think about switching to the next-deepest deco gas. It'll still probably be useful.
My dive buddy and I primarily dive SM, and today, we dived a quarry to practice our AN/DP skills -- swim a route, ditch-and-don two deco tanks, blow a bag, practice two NOTOX gas switches on the way up. Not a huge deal...we were only in 20-40' of water and running drills we've done over and over again, but these are perishable skills, and we need to knock some of the rust off after a regrettably dive-light winter. And I was using new deco regs, so I needed to learn their quirks.
The first dive was chill. The second got exciting.
On the second dive, everything up to the second simulated deco hang went fine. We swam our route, completed skills along the way, blew our bags, and ascended to the target depth of 30'. There, we made our initial NOTOX switches, chilled out for 2 minutes, prepped the next switch while waiting, and then ascended to 20' for the second gas switch.
Everything went well until about a minute into the second hang, when I heard and felt a nearly deafening BANG and the water around me turned white. And, when I tried to inhale, nothing came in.
You guessed it...my second stage had popped off the hose, and a loose hose was whipping around, venting NOx50 like mad.
I kept my head. Mostly. I felt dazed from the blast, but reason quickly returned. I pulled the loose second from my mouth and replaced it with my necklace reg. In doing so, I lost my downline in the bubble storm and must've started sucking air like mad because I started to ascend, and went up faster -- much faster -- than I wanted to. Happily, I exhaled constantly so I didn't embolize, and I was right next to a buoy line, so I used it to arrest my upward motion at 10'. I then vented my bladder and drysuit, closed the offending tank, breathed air while I generally got my crap reorganized, and surfaced with my buddy.
So, basically, I experienced a lost-gas scenario/OOA during (simulated) accelerated deco and dealt with it successfully. But I could've done better.
Lessons:
1. Tighten down the second stage connections, especially when diving a new reg.
2. Chill, yo. Breathe evenly, especially when there's a problem.
3. Keep hold of my personal downline. If I exhale enough to sink and/or I emergency-vent, I can return to my target depth and avoid bending myself.
4. Air is a good choice, but once the situation is handled, think about switching to the next-deepest deco gas. It'll still probably be useful.
