The modern scuba diving regulator is a simple yet complicated piece of equipment. Without modern regulators divers would still be wearing diving bells on their heads. They have evolved from humble beginnings to be a very complicated piece of equipment. And if you want to dive it is an essential piece of a divering equipment.
The original setup for scuba diving involved a regulator set with 2 main pieces. The first stage that connects to a scuba tank and a second stage that delivered low pressure air to the diver. This was a simple setup compared to the modern regulator system. It shows just how far the sport has come.
With the original set of regulators your first stage would suffer from the pressure as you went deeper. The first sign was always the 2nd stage got harder to breath. The reason was simple and it comes down to physics. The water pressure would restrict the air flow. The deeper you went the harder it was to breath. This was solved by the invention of the balanced first stage regulator.
There was no SPG available at a price that was even affordable. To solve this problem came the J valve on scuba tanks. Any divers that have used this tank valve will tell you in was not good. It was great idea at the time I was once told. You had a lever on the tank valve. When your tank ran out of air just pull the cord on your left shoulder. This was connected to the lever. (Reminds you of the low on air signal closed right fist on the left shoulder). This opened the reserve section of your tank. By doing this you had access to more air. About 25%, enough to begin accent and safety stop.
If the tank lever wasn’t engaged when you were having your tank filled the reserve would remain empty. Remember you had no SPG. So your tank would not fill totally. You would not know it wasn’t filled totally. You then pulled the lever during the dive and got an out of air situation. During the dive if you accidentally pulled the lever or bumped it in a tight area. You would be using your reserve without knowing. It would then give you an out of air situation that was not expected. The J valve system is now gone and very few divers have even seen a J valve setup on a tank.
Octopus or Alternate air source regulators were very rare. The cost of a regulator was very expensive. Divers would have their 2nd stage and no alternate.. This was considered enough for a dive. It gives a whole new meaning to the term share air. And the old way of sharing was just that, you would share the regulator that was working between 2 divers. With development of BCD’s some manufactures added a regulator to the BCD inflator. This was a cheap way of having a second regulator. It makes sharing a little difficult during an emergency situation. But it was a good idea at the time.
With manufacture of diving regulators using modern methods and materials. For example modern plastics, mass production, we have seen the simple regulator set become cheaper, better designed, and with many more features.If you handed a diver today an old regulator set it would be rejected. We all use SPG, alternate regulators and low pressure fillers for BCD’s.
Today safety is the corner stone of the scuba diving industry. The days of going diving with 1 regulator and no air pressure gauge are history. The cost of the equipment has not changed a lot. But what you receive for your investment now is of far greater value. A set of balanced regulators with a combination of gauges. Low pressure inflators. And 2 regulators that you can rely on to deliver your air on demand. We have come a very long way.
PADI IDC Staff Instructor 331032
AUS DIVING ACADEMY