I wrote the following sometime last December, but never got it onto the other thread. Here it is, with some other comments below it:
I have been solo diving for approximately two decades now, and will discuss my own approach to it, and my background so you can make your own judgements.
My solo diving has been mostly, but not exclusively, fresh water lake or river diving. Much of it was in conjunction with either aquatic life observation, or photography. What I do, not too many others want to do or would tolerate for behavior from a buddy. For instance, Ive been known to spend ten to twenty minutes on a sandy bottom following the trail of freshwater mussels, observing very small critters interact with other critters (invertebrates like insect nymphs) or the aquatic environment, and photographing mating fish in a current. The red-sided shiners mate in May and June in the North Umpqua River, when the water temperature goes over 60 degrees, which I've documented with observations over the years.
But how many buddies could, much less would, dive with me to be tethered to the bottom in a 5 to 7 knot current to watch these mating interactions of the red-sided shiner, and the feeding of the Umpqua Northern Pike Minnow on the shiners? Not many would have the skill to follow me, much less the desire. So I did these kinds of observations alone on my lunch breaks from work. Much like runners go out for a run, or bicyclers go out for a ride, I went diving on my lunch break, and I saw some fascinating things too.
I should state that most of my solo diving occurred in freshwater rivers and lakes and in water less than 60 feet deep (usually less than 25 feet deep). Had I not begun diving solo, I would have given up the sport. Family comes first, and family activities precluded travel for diving most of the time.
So why would I continue diving, and dive solo, when I also am a safety professional? Well, it has to do with training and experience, a love of both biology and diving, and the need to commit to my family the time necessary to raise kids in todays world. I dont recommend solo diving to others, but will give you the training that I decided qualified me to do this kind of diving.
I started diving many years ago, and received training from both the US Navy and US Air Force in diving. In the Navy, solo diving was prohibited, and those who got too far from their buddy slept with and carried for 24 hours a buddy line, which was about 15 feet of 6 inch diameter rope used to tie up ships.
But in the US Air Force, one of our primary responsibilities was to parascuba jump from an airplane into the ocean to render aid to injured people. We usually jumped with other jumpers, but on occasion (either because of separation in the air, or mission requirements) jumped alone. Anyone who has seen James Bond in "Thunderball" has seen pararescue parascuba jumpers, as PJs performed the last scenes jumping from a C-97 to rescue Bond. Our mission to provide this aid was developed during the US Space Program, and Commander Scott Carpenter was a direct benificiary.
On helicopter rescues, we often jumped (either parascuba or from a hover) and trained to swim alone. When we jumped, we sometimes needed to recover things like a parachute from the water, on the end of a 60 foot tether (Apollo recovery). If it sank, we needed to get it back. At times, we needed to jump on different survivors, or to a different point to make a recovery. So in the US Air Force, we became comfortable solo divers.
As a diving instructor in the 1970s, we began discussing the buddy system, and what sometimes when wrong with it. Solo diving was a topic even then. One of the diving pioneers in underwater medicine, Dr. Standley Miles, had discussed accident prevention as a balancing act between the environment and the chance of accidents, accident proness, risk acceptance and physical factors that could produce an accident, balanced by training, maturity and safety measures which tended to keep accidents from occurring. My choice to do solo diving included an examination of my qualifications to dive, my own experience, and the ability to accomplish what I wanted to do while diving. It was always balanced by an examination of the diving conditions, and how I felt at the particular moment concerning the dive. There were times when I did not dive too.
Diving solo is mainly a question of how comfortable a person is in the water, what the person is actually doing, and how that person is equipped through both training and actual equipment. I have dived solo with double-hose regulators, for instance, and no redundancy at all. But this was shallow diving (less than 35 feet), mostly in fresh water. Now, I usually dive with at least an octopus second stage, and at times with a separate regulator.
Dr. Paul Thomas said below:
If you indend to dive solo my advice is to get a test to exclude a patent foramen ovale, first.
This is very good advise, and testing for PFO should be included in a diving physical. I've taken many USAF flight physicals, and think that would have been caught for me some time ago if I had it.
SeaRat
