I have been diving now for about 10 years, logged hundreds of dives and have never, ever been alone on a dive. Yes, experience does make a huge difference, but when something does go wrong like a failed regulator, out of air condition, entanglement in vegetation like kelp, disorientation inside a wreck, narcosis at depth, etc. (and it eventually will if you dive long enough) it is paramount that you have someone with you to help out. When I first started diving back in the mid 90's, I too had it beat into my head to NEVER EVER dive alone. I thought, ok I am a pretty smart and level-headed person. I was in the military at the time and had gone through lots and lots of highly specialized and pressure-intense training. I was a Naval Officer and had been trained to remain level-headed even during chaotic circumstances. I thought to myself, "This is nothing. If I ever get into trouble, I can take care of myself and I won't panic. I'll just use the training I have and respond the way I have practiced so many times." Well, that sounds really good in your head, but the honest truth is that when you do get into trouble the first few times, YOU DO PANIC a little and fear does some strange things to that rock-hard ego inside that tells you that you can handle anything. And even with a buddy next to you or a few meters away, you still feel a little isolated and alone. It was not until after 100 or so dives that I built up the confidence in my own abilities and skills to venture 20-30 feet away from my dive buddy or out of their line of sight. Because getting into trouble (like getting caught on something, having your tank come loose, or losing a piece of equipment in strong current , etc) is only compounded when your are alone or far from your buddy. I recently (after 10 years of diving experience) completed the Advanced Open Water course and am enrolling in the Emergency First Responder course as well. I had certainly experienced (many many times) the types of diving we did during the advanced course, but I still learned a great deal about diving and how to respond to emergencies in advanced circumstances.
So to answer your question about what are the inherent risks of diving alone, I would have to say(especially for a new diver) that mistakes made due to FEAR are probably the most important additional risks you assume if you choose to dive alone. I do know several people who routinely dive alone on a regular basis. They are all extremely experienced divers that are either at the Master Diver level or beyond. I do not agree with their decisions to dive alone, but I do understand their love for the sport. Experience is one thing, and goes a long way when something goes wrong. But it does not take the place of another person's ability to remain level-headed and calm during a diving emergency. Having a buddy with you increases the probability that you will respond appropriately during an emergency and they can assist you and possibly save your life should you suffer any medical trauma on your way back to the surface. Imagine you have an out-of-air condition and you have to do a controlled emergency ascent to the surface. Well, if you have never actually done this for real (I have once), controlling your emotions and general tendencies to "freak out" is a little harder than you might think. Having a buddy's spare regulator or pony bottle, or spare air can make this emergency a more controlled one. Also, if you are injured, who is going to help you once you make it to the surface. You certainly cannot give yourself CPR, for instance. How would you make it out of the water, back into the boat, or back to shore without assistance? This is just one circumstance out of hundreds that you could find yourself in if you are diving alone.
The choice is obviously still your's to make, but I would highly recommend that one not feel so confident in his/her skills that common sense gets pushed aside in the process. Depending upon your skills, equipment, and training is a necessary component in this sport, but common sense is also pretty important. Your ego and faith in your ability is not going to save you in an emergency, but a buddy certainly can and probably will.
DavidHickey:
I probably should have kept this on the post below, but I'm just curious guys I'm really new to diving, and I've read alot on the horrors of solo diving here on the board. I've read how dangerous it is and how you should have 1000's of dives before ever attempting it and should by NO means EVER consider it unless you can snatch the pebble out of the masters hand. BUT I have never read any reasons why people are so strongly against it. For instance my dives to date have been in shallow gravel pits 30' or so and in shallow tropical areas about the same depth. From these depths in good dive conditions can you explain the dangers you may face that would make this any more dangerous than snorkeling solo in the same waters? I am by NO means trying to say there are not dangers but being new and naive, I think to myself that in a worse case scenario you simply do a CESA inflate your BCD and swim to shore. Once again I'm not advocating solo diving, just wondering what hidden dangers await that basic scuba skills we are all taught could not remedy at these shallower depths. Most the answers I've read are to the extent of "If you have to ask your not ready" well thats not a real informative answer.
