As always TSandM, a thoughtful, detailed, considered response. Thanks for your contributions on SB. I find you provide a valued perspective here.
To the Original Post - The term "required" for a safety stop is perhaps a bit imprecise. Yes, safety stops are valuable and definitely should be done. My understanding is that research on how offgassing occurs in the nervous systems (spinal column tissues etc) demonstrates that those few minutes maintaining the 15ft of water pressure helps significantly to manage the pressure differences key in bubble formation in tissues of this type given their half times - important for safety. However, if I'm separated from my buddy, I will miss the stop.
Sure there are tough scenarios - what if it was the very end of a dive where I had pushed my tables/computer to the max and only had 1 minute left for my NDL when my buddy got separated from me?... I'd be cursing myself for being so stupid - since I shouldn't be working tables, or a computer, that close (IMO)... and i'd still be looking for my buddy at depth for 1 minute if possible, and ascend to the surface without the safety stop to find him/her.
In my view - with Basic OW training or AOW training -keep within a safety margin so you could look for a minute and surface safely and find your buddy either at depth, on ascent, or on the surface. Also, remember that without your buddy you are now solo diving without redundancy...
To the Original Post - The term "required" for a safety stop is perhaps a bit imprecise. Yes, safety stops are valuable and definitely should be done. My understanding is that research on how offgassing occurs in the nervous systems (spinal column tissues etc) demonstrates that those few minutes maintaining the 15ft of water pressure helps significantly to manage the pressure differences key in bubble formation in tissues of this type given their half times - important for safety. However, if I'm separated from my buddy, I will miss the stop.
Sure there are tough scenarios - what if it was the very end of a dive where I had pushed my tables/computer to the max and only had 1 minute left for my NDL when my buddy got separated from me?... I'd be cursing myself for being so stupid - since I shouldn't be working tables, or a computer, that close (IMO)... and i'd still be looking for my buddy at depth for 1 minute if possible, and ascend to the surface without the safety stop to find him/her.
In my view - with Basic OW training or AOW training -keep within a safety margin so you could look for a minute and surface safely and find your buddy either at depth, on ascent, or on the surface. Also, remember that without your buddy you are now solo diving without redundancy...