Debborah Lecocq and Samuel G. Lecocq

Until the mid-1950’s most diving equipment was tested in a very rudimentary fashion. The testing methods were similar to those employed by the Wright Brothers with their early airplanes. With no wind tunnels, laboratories or other facilities to test their flying machines they just fired up the engines and took to the air hoping they could manage a safe landing. It took guts and bravery, some might even say a reckless disregard for their own welfare. Likely it was a combination of these traits. The same situation existed in the design and testing of dive equipment until the mid-1950’s.

In January 1943 one of the first prototypes of the Aqualung was tested in the cold muddy water of the River Marne in Paris where visibility is practically zero. Jacques Cousteau jumped into the water without a wetsuit loaded down with bulky tanks and a demand valve regulator. Emile Gagnon watched from shore as Cousteau went below the surface. Dear Emile couldn’t swim at all and became quite frantic when Cousteau remained underwater longer than planned. He emerged from his dive shivering and coughing, with the report that the equipment worked, but just barely and certainly needed some modifications.

Later on an improved version was tested in the Mediterranean Sea off the coast of France by two brave swimmers. A risky proposition considering the equipment they used had never been tested to assure flow and resistance at depth.

When the first Aqualungs manufactured in France arrived in the U.S. partially assembled, the only testing device we had available at Rene Sports (later to become U.S. Divers) was a high pressure tank with a medical valve mounted on a test bench. We would simply attach a regulator to the medical valve and try to take a few breaths of air from the mouthpiece to see if there was sufficient air flow to deem it safe for diving. Again, there was no testing under pressure for flow or resistance, or testing under strenuous circumstances or in the unusual positions encountered by divers.

From time to time we would take a regulator mounted on a tank into the pool at the Bel Aire home of Rene Bussoz, the owner of Rene Sports and U.S. Divers. At the bottom of the pool in about ten feet of water we would breathe on the Aqualung. Then we began to take the units to Catalina Island, twenty-three miles off the Southern California coast. Descending into the beautiful clear water to 100 feet or so we would sit on the bottom and take a few breaths to test the inhalation and exhalation performance of the regulator. Then we would hang in the towering forest of giant kelp and try the inhalation and exhalation in various positions: prone, on our backs, with the head elevated and head down.

We soon discovered some flaws in the system. Breathing became more difficult at 100 feet. Breathing also seemed to vary with the position of the diver in the water. But what was more serious, we discovered if we took the mouthpiece out of our mouth and even a small amount of water entered the hoses it was extremely difficult to clear water from the system in order to begin breathing again.

If the diver had sufficient air in his lungs he could roll over onto his side so the exhalation hose was above his lungs, exhale forcefully and clear some of the water. But the distance from the exhalation valve to the mouthpiece made it difficult to remove all the water and the diver would usually aspirate some saltwater on the next inhalation cycle. More importantly, the diver had to be forewarned that this technique was necessary any time the mouthpiece was removed or accidentally dislodged from the mouth which allowed water to enter the hoses.

It was only with the introduction of the Hope Page non-return valve in 1954, a component with two one-way check valves that was installed in place of the standard mouthpiece, that the Aqualung became safe. The Hope Page valve was a beautifully designed unit manufactured from a solid block of a special aluminum alloy that was hard anodized.

When water entered the mouthpiece the first one-way valve prevented the water from entering the intake hose. On the other side of the mouthpiece another one-way valve kept any water in the exhalation hose from entering the mouthpiece. It made it easy to clear the mouthpiece and prevented any residual water in the corrugated hose from entering the mouthpiece where it could be inhaled during the next cycle of breathing. The Hope Page design of two one-way check valves was incorporated into all Aqualung regulators manufactured from that time on.

One of the first people to buy an Aqualung from Rene Sports was Perry Bivens, a young engineer from Douglas Aircraft in Santa Monica. Perry and I soon became friends. He had a passionate interest in the effects of different gases on the human body, especially under pressure. He designed a decompression chamber and contracted to have it built by a local steel company. The chamber was installed on his parent's property, a few hundred yards below their home in Mandeville Canyon, an exclusive wooded area near Los Angeles.

During a weekend of diving at Catalina Island with Perry, Zale and some friends, we decided to incorporate a more scientific approach to the testing and evaluation of diving apparatus by using Perry’s hyperbaric chamber. Some of our friends volunteered to become guinea pigs and test equipment in the chamber. Bill Milham, who remains to this day one of my closest friends, was one of our best test subjects. He had a low tolerance for nitrogen narcosis and at the relatively shallow depth of 90 feet (simulated by pressure in the chamber) his responses to our questions over the intercom were often very interesting and amusing.

Perry, Zale, and I became very good friends and our mutual interest in diving equipment led to more and more testing in his chamber. As new diving units were introduced on the U.S. market we tested each one: the Divair Regular manufactured by Arpin Company, which was the first single stage two-hose regulator, and Aqualung’s Jet Air regulator, which later became the DY and DX, just to name the first two. As a result of our tests on the Jet Air I redesigned it to make it a more reliable unit.

Then in 1956 I began designing a single hose regulator and for the following two years, with the help of Perry Bivens and his chamber, we tested what was to become the Waterlung. Each modification of the single hose prototype was tested, first in a lab I had set up, then in the chamber and later in the ocean.

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Perry Bivens and his wife Zale Parry helped with the testing during dives at Catalina. Another friend, Captain Walter Miller who was director of the Pacific Missile Range at Point Mugu, California provided us with PT boats and together with his Navy divers we

controlling the depth by changing the pressure inside the chamber. I worked in the chamber for over an hour as Perry simulated various depths by increasing the pressure. During that time we had been communicating over the intercom about the performance of the unit, and then chatting and joking about life in general just to pass the time. After reaching a maximum simulated depth slightly less than 200 feet, Perry started reducing the pressure to simulate an ascent. After a few decompression stops, at a depth of 10 feet, Perry simulated the final decompression stop and told me we would remain at that depth for about 30 minutes. He said he was going to the house to have a cup of coffee and would be right back to bring me to the surface.

Photo by Zale Parry

After a few minutes I realized I was captive in the chamber, under pressure with all the controls outside the chamber. There I was, virtually helpless, with nobody around if something went wrong. I had no watch and no concept of how much time had elapsed since Perry had left for coffee. My anxiety level began to rise. My mind raced through the dire consequences I could face if Perry had been injured on his way to the house. What if he’d forgotten me? I was in a steel tube at the bottom of a canyon with a limited supply of air and no way to escape. I started to shout and bang on the heavy steel door, but the chamber was so remote that no one could hear me. Just then I heard the alarm bell of the timer that Perry had set to signal the end of the decompression stop. After a few very nervous moments I heard Perry’s voice on the intercom, very calm and nonchalant, telling me he just got back in time for the next ascent.

After he brought the chamber back to atmospheric pressure and opened the chamber I stepped out into the sunlight, blinking, and grateful to be free. I told him I had been near panic realizing the predicament I was in, captive within the chamber with no way to control my own ascent. We abandoned testing for the rest of the day, went up the hill to his house for a stiff drink. We decided in the future to conduct all testing with two people inside the chamber and two outside at the controls. To my knowledge Perry and I were the first to test diving equipment under a simulated depth in a hyperbaric chamber.

The Waterlung was introduced in 1958. Perry Bivens interest in the effects of pressure, gases and chemicals on the human body led him to enter medical school. He became a medical doctor, continued his research and died tragically a few years later.

Zale Parry became one of the most accomplished women divers and a star of movie, television and print media. She endorsed the

the University of Southern California. Thanks to all of these friends and many others. Without their help the Waterlung would not have evolved to become the single hose regulator that changed the world of diving.

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The above is an extract from the book by Samuel G. Lecocq Unfogging the Mask; Evolution, Intrigue and Controversy in the development of Scuba.

© 2008 Samuel G. Lecocq and Debborah Lecocq
All Rights Reserved.