DIVE DRY WITH DR. BILL #846: (**)IT HAPPENS!
There is a saying that goes something like this... remember the days when reproduction was safe and diving was dangerous? Well, OK... they did use a slightly different word, but I don't want parents to have to explain that to their five year old reading this. Today, with all the modern advances in SCUBA gear and the deadly STDs that have surfaced, the reverse may be true. I thought I'd spend some time focusing on the dangers I have experienced during my 57 years on SCUBA. I have little to no experience in that other activity so I can't comment there.
In the good old days, I dove with what is now referred to as "vintage equipment." Back then we had no BCDs, SPGs, octos or dive computers. A few of my students could afford inflatable Mae Wests or horse collars, but that wasn't prudent on a teacher's salary. We had to weight ourselves according to the depth we planned to dive. When our air supply got low, we pulled the rod connected to our J-valve and had a bit more gas to surface on. We relied on dive tables to tell us how much residual nitrogen we had to avoid getting the bends. Those were the days... NOT!
One day in the fall of 1969 one of my marine biology students wanted me to descend with him to 90 ft to photograph a "worm" with a Nikonos underwater camera. We grabbed two tanks off the "filled" rack but there was no topside pressure gauge to check them. Relying that someone followed proper procedures and the tanks were full, we descended to depth.
As soon as we found the "worm," my student started waving his hands frantically. It took a few seconds for me to realize he was low on air, so I checked his J-valve rod. It was already down. We started our ascent buddy breathing and my tank began breathing hard. My J-valve rod was down too. Apparently someone had placed "empty" tanks on the filled rack. Fortunately we made it to the surface... or you would never have had the chance to read all my scintillating columns.
Years later, I planned to descend to 40 ft and didn't carry my pony bottle. A smart solo diver will carry this redundant air supply in case the main tank fails. I ended up following a bat ray down to 80 ft when my air supply suddenly failed. Good training and experience had me instinctively rising to the surface as soon as that happened. I ascended for 70 seconds, reaching the surface huffing and puffing. It turned out that a tiny particle of debris inside my tank had fallen directly into the tank valve's debris tube, cutting off all air. A highly unlikely scenario, but it happened.
Of course even with modern gear things still can go wrong. Back in 1989 I was told I had to wear a buoyancy compensator (BCD) while diving with a Cousteau team off Santa Cruz Island. In 27 years on SCUBA, I had never used one. I tried descending several times, but the BCD popped me right back to the surface. I told the dive master that I thought it was automatically filling up with air. She watched me try again and agreed, then asked me what we could do. I said I would disconnect the inflator hose and dive without the BCD! She seemed surprised a diver could do that.
I got my first dive computer, an Orca Skinny Dipper, back in the 1990s. A few years later I decided I needed a newer one so I bought an Aladin Pro Nitrox. It was much easier to use and I quickly forgot dive tables. However, just as with my first BCD, even this valuable technology can fail. I was slowly surfacing from a 180 ft dive with many minutes of deco ahead of me when the computer battery died. The display had said the battery was still 38% full, but I learned later that it used an algorithm to estimate battery charge rather than measuring it directly. I soon started diving with two dive computers for redundancy.
Today I wouldn't dive without the modern conveniences we lacked back in the "good old days." I rely on my SPG to tell me how much air remains in my tank. Fortunately it is pretty accurate. Although I still make small adjustments in my buoyancy using my lungs, I wouldn't dive without a BCD. I dive solo almost exclusively (except when I travel and am buddied up) so I usually don't have an octo attached to my reg.
The one thing I've been lax on the past few years is taking my pony bottle with me on solo dives. I really should, but several years ago I had minor abdominal surgery and couldn't risk the extra weight. So instead, I create additional risk to my life. The odds are with me, but... I could also win the lottery. I really need to be more prudent as I evolve into a real old geezer! Still not sure if I'm ready to tackle that other activity that they tell me has become far more dangerous. Gulp!
© 2020 Dr. Bill Bushing. For the entire archived set of nearly 850 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Things we didn't dive with way back when: SPG, BCD, octo and dive computer.
There is a saying that goes something like this... remember the days when reproduction was safe and diving was dangerous? Well, OK... they did use a slightly different word, but I don't want parents to have to explain that to their five year old reading this. Today, with all the modern advances in SCUBA gear and the deadly STDs that have surfaced, the reverse may be true. I thought I'd spend some time focusing on the dangers I have experienced during my 57 years on SCUBA. I have little to no experience in that other activity so I can't comment there.
In the good old days, I dove with what is now referred to as "vintage equipment." Back then we had no BCDs, SPGs, octos or dive computers. A few of my students could afford inflatable Mae Wests or horse collars, but that wasn't prudent on a teacher's salary. We had to weight ourselves according to the depth we planned to dive. When our air supply got low, we pulled the rod connected to our J-valve and had a bit more gas to surface on. We relied on dive tables to tell us how much residual nitrogen we had to avoid getting the bends. Those were the days... NOT!
One day in the fall of 1969 one of my marine biology students wanted me to descend with him to 90 ft to photograph a "worm" with a Nikonos underwater camera. We grabbed two tanks off the "filled" rack but there was no topside pressure gauge to check them. Relying that someone followed proper procedures and the tanks were full, we descended to depth.
As soon as we found the "worm," my student started waving his hands frantically. It took a few seconds for me to realize he was low on air, so I checked his J-valve rod. It was already down. We started our ascent buddy breathing and my tank began breathing hard. My J-valve rod was down too. Apparently someone had placed "empty" tanks on the filled rack. Fortunately we made it to the surface... or you would never have had the chance to read all my scintillating columns.
Years later, I planned to descend to 40 ft and didn't carry my pony bottle. A smart solo diver will carry this redundant air supply in case the main tank fails. I ended up following a bat ray down to 80 ft when my air supply suddenly failed. Good training and experience had me instinctively rising to the surface as soon as that happened. I ascended for 70 seconds, reaching the surface huffing and puffing. It turned out that a tiny particle of debris inside my tank had fallen directly into the tank valve's debris tube, cutting off all air. A highly unlikely scenario, but it happened.
Of course even with modern gear things still can go wrong. Back in 1989 I was told I had to wear a buoyancy compensator (BCD) while diving with a Cousteau team off Santa Cruz Island. In 27 years on SCUBA, I had never used one. I tried descending several times, but the BCD popped me right back to the surface. I told the dive master that I thought it was automatically filling up with air. She watched me try again and agreed, then asked me what we could do. I said I would disconnect the inflator hose and dive without the BCD! She seemed surprised a diver could do that.
I got my first dive computer, an Orca Skinny Dipper, back in the 1990s. A few years later I decided I needed a newer one so I bought an Aladin Pro Nitrox. It was much easier to use and I quickly forgot dive tables. However, just as with my first BCD, even this valuable technology can fail. I was slowly surfacing from a 180 ft dive with many minutes of deco ahead of me when the computer battery died. The display had said the battery was still 38% full, but I learned later that it used an algorithm to estimate battery charge rather than measuring it directly. I soon started diving with two dive computers for redundancy.
Today I wouldn't dive without the modern conveniences we lacked back in the "good old days." I rely on my SPG to tell me how much air remains in my tank. Fortunately it is pretty accurate. Although I still make small adjustments in my buoyancy using my lungs, I wouldn't dive without a BCD. I dive solo almost exclusively (except when I travel and am buddied up) so I usually don't have an octo attached to my reg.
The one thing I've been lax on the past few years is taking my pony bottle with me on solo dives. I really should, but several years ago I had minor abdominal surgery and couldn't risk the extra weight. So instead, I create additional risk to my life. The odds are with me, but... I could also win the lottery. I really need to be more prudent as I evolve into a real old geezer! Still not sure if I'm ready to tackle that other activity that they tell me has become far more dangerous. Gulp!
© 2020 Dr. Bill Bushing. For the entire archived set of nearly 850 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Things we didn't dive with way back when: SPG, BCD, octo and dive computer.
