I have an old Doctor friend who happens to be an expert in hyperbaric medicine, especially as it pertains to sport divers (although his training was in the Navy) and he spent much of his career studying and treating rec. diver accident victims. One of his more memorable lines is, "We can fix bent, we can't fix dead."
Back in the day, before silent bubbles and dive computers were invented, we had a way of amusing ourselves during a mundane dive. We'd swim down maybe 60 or 70 feet, hang on to a giant rock, inflate our "life-vests" (And I was using a Fenzy at the time, which has, I think, about 12,000 pounds lift, just slightly less than my 20' Zodiac) and let go. We would come rocketing to the surface, clearing the water to our waists. We were breathing REALLY fast on the way up, but it was pretty amusing. Nobody ever got bent or embolized or anything of the sort. I'm not suggesting in any way that this is a good idea, but my point is that this whole ascent speed thing really only matters when you're already somewhat bubbled up. As long as there is no air being trapped anyplace, nobody is going to burst anything either.
(And just to be clear, we were young, stupid and perhaps a titch reckless, and I am NOT suggesting that this, in hindsight, was a great idea.)
In this case, you were minutes into a dive, so everyone had lots of air and no nitrogen loading to speak of. You describe the free-flow as fairly minor, so I think simply calling the dive and herding the two students up would have been an entirely appropriate response, perhaps with a firm grip on the dude, just in case he became overly enthusiastic in his with to reach the surface.
Having said that, I wee freeze-up can turn into a MOAFU (Mudder Of All Freeze-Ups) pretty quickly, potentially... so your response was also entirely appropriate.
Well, all except the worrying about the SBA (Screaming Buoyant Ascent). 'Cause if you had done anything wrong while you were "in transit", then you probably wouldn't be here talking about it!
How about this lets thread on the side of safety, we can crunch all the numbers we want and say no safety stop is required. How about not making a third victim? We do not know the physiology of the diver, We are not doctors, No one can truly guarantee or say by this guy missing his stop he wont get bent or experience some kind of DCS. Diving is theoretical
I'm going out on a limb here and I'm going to say that I think we can guarantee that. At 6 minutes into a dive and only a few minutes actually at 85', I think we can say with a high degree of certainty that the risk of DCS is statistically zero, unless the third guy is a freak of nature. Conversely, this is a teaching situation and the OP, who is the Instructor, has the responsibility for the well-being of all of his students, not just the guy with the fizzy reg. If the second student had stopped to do a safety stop, that's three minutes where he is out of sight of the instructor, and on his own. (And I get the impression that this was the guy with only 15 dives). That's exactly how an "interesting" dive becomes a tragic one... A novice diver, "abandoned" by his Instructor and left alone.
In this situation, the worst thing that might have happened is that all three of them would take a minor hit... which would be easily treated. In your preferred situation, the third guy (with a handful of dives) loses control of his buoyancy, sinks, spooks himself, freaks, panics and rockets toward the surface embolizing along the way. And now we're back to where we started: You can fix bent. You can't fix dead.
So I am going to respectfully disagree with you WF21. The OPs reaction was to keep his little guppies together and get them to the surface. He did that, and that was the right thing to do. There were no "victims" of any sort in this dive... Just a diver or three who are a little wiser than they were when they entered the water.
If it was an emergency situation I would of course abort the safety stop - otherwise it is a safety stop for me. Meet you at the top after a 3 min stop @ 20 feet. But my buddies would know this before we hit the water.
