Reminiscing about the early days of SCUBA – Part 1

This desire to participate in underwater experiences, and there are several in SCUBA (Tech, Wreck, Hunting, Cave, and many more) doesn’t just materialize in our heads. Instead, I believe it’s a result of the total sum of our life-long experiences, inspired through our education, culture, family, religion, school, television, peers and other sources.

I for example grew up watching black and white episodes of Sea Hunt on television. For me, Lloyd Bridges and the character he portrayed in his TV series shaped many of my own desires for underwater exploration. Later on, Jack Cousteau’s adventurous episodes about ocean research helped me understand many important principles of marine science and SCUBA diving as well. So it’s only natural that about a year ago when I noticed a lady bring an old school regulator to Peter Friedman’s dive shop in Stuart Florida I wanted to buy it. That regulator, one that looked just like the one Lloyd Bridges used in his series, was not in working condition but to me that didn’t matter, it was a part of history which I personally identify with.

Peter gifted me the regulator – I can’t tell you just how much this meant to me especially when I examined the back plate and inscribed there, saw “Aqua-Master 2 Stage Regulator” and the names “Cousteau – Gagnan.” Wow, what a thrill to own a small part of SCUBA history.

Almost a year later, another friend, Scott Beckham, owner of Sea Level SCUBA in Melbourne, Florida repaired the regulator. Now that I own a piece of SCUBA history that works I can’t wait to try it. But whoa – that won’t be as easy as it sounds. There are important differences between my old school demand regulator and the modern regulators in use today. These differences will require changes to my equipment configuration and how I dive. Here are a few important things I must consider before attempting a dive with this older regulator.

Note that this is not a guide on how to use this old type of regulator and I am in no way providing any technical specification but instead, a short view of my experience as a diver who is happy and anxious to use it.

1. Pressure Limitation. – Scott had me test the regulator using an LP Steel 72 tank rated at 2250 PSI while holding 64.7 cu ft of air and sternly warned me that I should NEVER exceed that pressure with this old regulator. And while I could use a tank with more capacity I am still limited to 2250 PSI. So I am purchasing an LP Steel 72 tank – I’ll have to explain to my wife later why I need yet another SCUBA tank LOL. I believe an LP Steel 72 would be perfect for short shore dives like Blue Heron Bridge, one of my favorite dive spots. The other reason for buying the LP Steel 72 is that it’s a perfect era match for this regulator.

2. No low or high pressure ports. – The regulator has a built-in low pressure connection that delivers air on demand to a fixed hose and mouthpiece. There are no low pressure ports for octo, inflator hose, or high pressure ports for a surface pressure gage (SPG). Without an SPG you would not know how much air is left on your tank until you run out. Back in the day when this regulator was in use, divers used K valves on their tanks. With a K valve, when a tank reaches a pressure of 300-500 PSI, the air supply stops. A small manual lever on the valve allows air flow to resume so the diver can surface.

3. Safety measures. – From a safety point of view, a 300-500 PSI tank pressure would not provide an adequate supply of air to ascend from depth and perform a 3 minute safety stop. I would not use this equipment configuration for a dive exceeding a depth of 20 feet – that is a personal choice. I understand that some may disagree with this estimate and that’s fine. I would rather play it safe.

4. Surface Consumption Rate (SCR). – Another consideration has to do with Surface Consumption Rate (SCR) at depth. I would not try to use the abovementioned equipment configuration and should calculate my SCR to time my dives with this new configuration, and ascend before my K valve cuts off the air supply. What else could I do in order to make this a fun and safe experience? In my case, I plan to bring a 30 cubic foot deco bottle just to make sure I will have sufficient air to return to shore or reach surface if anything goes wrong.

5. Flotation device. – I can certainly use my Buoyancy Control Device (BCD). However, because there is no connection for an inflator hose, I will have to inflate my BCD orally and deflate it manually. This is a skill we learn in Open Water training but also one which we do not practice enough.

6. Purging the regulator. – There is no purge valve on this regulator and as it was explained to me, you must shift your body to one side in order to accomplish this.

7. Skills required. – Using this regulator is not something I recommend for a novice diver, or any diver for that matter unless they have assistance from a diver who is well experienced in the use of this piece of equipment.

Diving with this old regulator presents risks and requires physical strength, knowledge, and experience. Do not use this regulator unless you thoroughly understand how to use it. Also, have a knowledgeable individual examine the regulator to make sure it works properly and that the interior components are in good condition. Furthermore, you should have an experienced diver assisting you the first time you use this regulator and begin your immersion in water shallow enough so that you can stand up in the event anything goes wrong.

In Part-2, I will share my experience diving with the regulator. Hopefully I will have some underwater photos for you.

Until then, calm seas and please stay safe.

Uncle Ed Zayas