TIPS CURIOSITIES

Regulator

Text WOJCIECH A. FILIP

Photo Tomasz Płociński

In 1867, Jules Verne saw the first diving suit at the Paris expo – the suit later worn by protagonists in his book “20,000 Leagues Under the Seas”.

The book mentions two names: Rouquayrol and Denayrouz. The former was an inventor, who patented a breathing apparatus in 1860 to help miners escape from flooded mine galleries and several years later Rouquayrol and Denayrouz patented a classic diving suit equipped with a breathing system. A little earlier – in 1838 – another Frenchman called Guillaumet invented a reducer to use gas in a controlled manner by effectively decreasing its pressure. And some time after that – in 1943 – two well-known individuals appear in the diving world: J.Y. Cousteau and E. Gagnan. Cousteau and Gagnan modified the device invented by Rouquayrol and Denayrouz. Does that mean that a regulator first came onto the market at that time? Not exactly. The breathing apparatus, which was later modified by Cousteau and Gagnan, had been mass-produced since 1865. Their company, La Spirotechnique, started to commercially market the regulator called CG45, which was later renamed to... Aqua Lung (finally, a name we’ve heard of!). Initially, Aqua Lung was the property of U.S. Divers, a US company, which later changed its name to Aqualung America. And Bob's your uncle 

Do we know who invented the first regulator? No. We know that your regulator is a version of Cousteau’s and Gagan’s invention that has been modified to various extents. Does it mean that all regulators are the same and just look differently? In a way, yes.

What regulator should I buy?

What to do when a regulator falls into water (with no cylinder attached)? We will discuss it the second part of the article.

Is it a good idea to use the adjustment wheels on the second stage, and if so – how to do it?

Enjoy the material on regulators. You will find out how to make full use of your regulators, how to prepare them for different types of dives and maintain them. Answers will also be provided to some questions you didn’t think to ask. To make information interesting both for beginners and advanced divers, Tecline Academy articles will be more clearly divided. Check out which version suits you best. I encourage you to read the entire issue and if you have any questions, do not hesitate to write in one of the Perfect Diver’s social media channels.

For advanced divers:

How to entirely prevent a regulator from freezing? How to replace regulators underwater? Is an increased breathing resistance beneficial when decompressing on oxygen?

Is my regulator the best there is?

If you have bought it recently, it is very likely. Important for every diver, regardless of their skill level. In 2014, the standard governing requirements for diving regulators was drafted and came into force. Compared to the previous EN250 standard, it imposes greater requirements for easy breathing (less respiratory work is required), even when a regulator is used by two divers. It meant that many manufacturers had to significantly modify their products. Certain regulator models of less – and well-known manufacturers disappeared from the market. They were replaced by new regulators that meet the strict requirements of the standard and, consequently, improve our breathing comfort underwater. What is a ”standard”? What does it mean for us divers? What a diver buying their first regulator should know about the standard?

Photo Michal Sevecek Photo Tomasz Płociński

The EN 250/2014 standard is (from a diver’s point of view) a set of requirements imposed on the regulator manufacturers by the European Union, allowing for determining exactly how a regulator should behave under different conditions, e.g. in very cold water, when used by two extremely stressed out people, when a regulator is very hot or... under standard conditions.

Buying a regulator compliant with EN 250/2014 The latest standard made shopping much easier. The requirements imposed on regulator manufacturers, forcing them to increase safety, eliminated poor-quality equipment from the market. It means that beginners may buy regulators almost at random. Each new regulator meets the same technical requirements in terms of breathing comfort and operation in cold and warm water. We only need to take into account our personal preferences: hose configuration, shape or color of the regulator. Each regulator that meets the requirements of EN 250/2014 has permanent marking on the first and second stage regulators: WHAT TO TAKE INTO CONSIDERATION WHEN BUYING A REGULATOR?

` make sure that the manufacturer has a network of easily accessible service points in your country; ` check whether your selected first stage regulator model has hoses that fit close to your body (and do not create loops); ` (ask the seller to show you how hoses are arranged on an assembled rig); ` put on your diving gloves and check whether you are able to easily handle all the adjustment knobs when holding the regulator in your mouth; ` if you always dive with the same team, ask you teammates about the regulators they use – do not buy a regulator if none of your teammates uses it (it will be important when you go together on trips and need spare parts).

Photos Bartek Trzciński

Are you not certain which first and second stage regulator to choose? Do you lack experience with proper hose configuration? Ask an authorized equipment consultant or an advanced diver you know Before you ask for help, review information on the new EN 250/2014 standard once again to make sure that your consultant tries to be objective. Remember that you will be the one using your regulators and you should be happy with them.

What does it mean that a regulator is intended for warm water? At most diving sites all over the world, water is much warmer than in Central and Northern Europe, and, consequently, divers use regulators with a lighter design that are not suitable for very cold water (below +10 degrees Celsius). On a global scale, such regulators are sold the most often. In Europe, they meet the requirements of the aforementioned standard, but only for dives in water with a temperature above 10 degrees Celsius. Such regulators are great for travelling, as they are lighter and usually less expensive than cold water regulators. If you live in a region where water is below 10 degrees and you like ice diving, make sure that your regulator is not marked as suitable for “+10 degrees Celsius”.

Cold water regulators are also suitable for tropical waters.

EXPERIENCE

Conduct a short and educational experiment: ` sit straight on a chair and bring your chin to your chest, ` pinch your nose with your fingers and breathe through your mouth, ` now, raise your head and look at the ceiling, ` pinch your nose and breathe deeply through your mouth. Open airways (with your head raised high) create much less breathing resistance. This position may make you think of providing CPR, when keeping the airways maximally open is also important.

Photo Bartek Trzciński

Breathing underwater The most important underwater breathing rule is this: the easier you breathe, the safer your dive is: ` you consume less gas, ` your gas narcosis level is lower, ` you will control buoyancy better. A perfectly adjusted regulator will help you breathe, but... it will be most effective when your head is tilted backwards and, consequently, your airways create the least resistance during breathing.

Head position underwater and breathing comfort What does it mean that your head should be tilted backwards, like in our exercise, when you were looking at the ceiling? It means that you need to position your equipment (mainly the first stage regulator) behind your head in such a way that it does not prevent you from tilting your head all the way backwards. If you learn to swim in such a position, you will breathe easier and control buoyancy better. What happens when you dive with your chin close to your chest? Breathing will be difficult. As a result, your diaphragm (a large muscle helping you to inhale and partly to exhale) will be forced to work harder than usually. Great exertion means that you generate more CO2 (carbon dioxide) than usually and you start to breathe faster in an uncontrolled manner. You changed the position of your regulator: in the case of a single cylinder – the regulator and cylinder are positioned as low as possible; in the case of twin cylinders – first stage regulators form a “V” so that your head fits between them, the manifold is tilted backwards, and you should remember to have your heads tilted backwards as well during the entire dive. The benefits are twofold: 1. Lower gas consumption. Initially, you will use approx. 5–10% less gas, but after several dives you may discover that your gas consumption is lower by even 30%! Why is that? The position of your head caused you to produce less CO2, which slowed your breathing. 2. Better performance during buoyancy control exercises. The reason for that is the same: less CO2, smoother breathing instead of uncontrolled inhales and exhales resulting in uncontrolled jumps to the surface.

Photo Mariusz Czajka

Your breathing is largely dependent on the carbon dioxide levels in your body. The higher the CO2 level, the faster (but usually not deeper) you breathe. The need to breathe is not caused by low oxygen levels, but by high CO2 levels. Fast and shallow breathing caused by lowering your head means that you get more tired, which causes your CO2 levels to climb even higher and your breathing gets faster still.

Do you remember your “Rescue diver” training? ` stop, ` breathe deeply, ` think

These three steps may help you get rid of some CO2 and slow your breathing. If you notice that your breathing gets faster, you should: ` tilt your head backwards, ` exhale slowly and deeply, ` hold on to something or someone.

Can it be improved further?

Proper use of regulators reduces gas narcosis More than a century ago, two anesthesiologists, Overton and Meyer, found that the narcotic effects of carbon dioxide are 20 times as strong as those of nitrogen. Some divers disregard the scientific research and think that only nitrogen causes narcosis. However, CO2 poisoning results in numerous disorders in our bodies. We know that elevated CO2 levels cause us to breathe faster, which may bring about underwater shortness of breath – it may be very dangerous and even lethal. We also know that there is a simple solution to that: keep your airways open so that you do not overproduce CO2. If you could also adjust your regulator to make breathing even easier, than... CO2 levels would drop even lower, your breathing would stabilize, you would have better buoyancy control and use less gas.

What about narcosis? 1. CO2 intensifies nitrogen narcosis that we are intimately familiar with. A minor Martini effect, coupled with a little exertion, may cause you to see predatory underwater monsters everywhere – better to avoid it. 2. Increased CO2 levels affect not only breathing, but also the perception of your surroundings. The specific narcosis related to high CO2 levels in the diver’s body causes them to get stuck on their recent task. The diver does not react to their surroundings, but has a vague impression that, for instance, they were supposed to follow their partner. So they swim and their CO2 levels are continuously increasing. Their breathing gets faster and shallow and without help, after some time the diver sinks to the bottom… 3. Do you usually use nitrox? You surely do, as the benefits of Nx are well known to every diver. So you know that the increased oxygen partial pressure results in oxygen being “stored” in your body. Too much stored oxygen (exhausted oxygen toxicity clock) is not ideal, as you may experience the most dangerous situation in diving – oxygen toxicity, called o-tox or just tox by divers. It almost always has a tragic end. Can you guess what may cause an oxygen toxicity attack, when there is too much oxygen in your body? CO2! This gas is particularly dangerous, which is why it is very important for each diver to limit exertion in any way possible.

RETENTION

A persistent elevated CO2 level in your body is called “CO2 retention” by divers.

Let’s sum up The way you breathe underwater directly impacts your safety. With each breath you produce carbon dioxide, which is dangerous for a diver. Diving with your head lowered or fast breathing will result in CO2 levels increasing and, consequently: ` you will use more gas, ` you will have poorer buoyancy control, ` you will start having trouble with inert gas narcosis.

What is the solution? Always dive with your head tilted back – it will help you control your breathing. Additionally, your regulator also affects your breathing.

Photo Karolina Sztaba

What are the adjustment knobs on the second stage regulator for? 1. Cracking pressure adjustment knob – the outermost adjustment knob used to control breathing resistance. The tighter it is (turning it clockwise), the harder it gets to breathe (and the higher CO2 levels will be). If the cracking pressure adjustment knob is completely unscrewed (by turning it counterclockwise), the regulator will supply gas with the least resistance (and the CO2 levels will be lower).

When diving, you always want to have your cracking pressure adjustment knob unscrewed!

2. Breathing adjustment lever called “Venturi effect lever”. We are interested in two lever positions: “+” (plus) and “–” (minus). Your breathing will be supported the most when you adjust the lever to the “+” (plus) position by bringing it close to your mouth. You can turn off the support by adjusting the lever to the “–” (minus) position, which can be done by withdrawing the lever from your mouth.

When diving, you should adjust the adjustment lever to the “+” (plus) position, i.e. bring it close to your mouth.

Please keep the following in mind: While the cracking pressure adjustment knob may be left in the least resistance position, the Venturi effect lever should be treated similarly to the gas pedal in your car – you need to learn how to use it to achieve the maximum effect, i.e. to reduce your CO2 levels 

Photo Bartek Trzciński

How to position the Venturi effect lever 1. When assembling the regulator, check whether the lever is in the “–” (minus) position before attaching the regulator to the cylinder. 2. When you test the regulator on the surface, the lever should be in the “–” (minus) position. 3. When you step/jump into the water, the lever should be in the “–” (minus) position. 4. When you talk on the surface before descending, the lever should be in the “–” (minus) position. 5. After you descend, the lever should in the “+” (plus) position. 6. When you ascend, the lever should in the “+” (plus) position. 7. After emerging from the water and before removing the regulator from your mouth, the lever should be in the “–” (minus) position.

Exceptional situations: ` when you descend head-first, the lever should in the “–” (minus) position. ` when performing underwater exercises that require removing the regulator from your mouth, the lever should be in the “–” (minus) position. ` when you are on a DPV, move the lever towards the minus position far enough so that the regulator does not supply you with gas between inhales.

When your diving position is untypical, e.g. when you take measurements or stabilize a reel line, it may be a good idea to slightly screw in the cracking pressure adjustment knob to adjust the regulator performance to a given situation.

Important! If you screwed in the cracking pressure adjustment knob and did not unscrew it until the end of the dive, you should unscrew it before placing the regulator in a storage bag. When you leave the cracking pressure adjustment knob screwed in for long periods of time, the material wears off faster.

If you adjust pressure adjustment knob and Venturi effect lever both to the “plus” position and press the by-pass button, while not holding the regulator in your mouth, it will trigger the regulator and cause it to supply a large amount of gas. In such a case, you should move the Venturi effect lever to the “minus” position. You should not hit the regulator against your palm or the water surface. Experienced divers change the position and setpoints of their regulators many times to adjust them to their current activities. They always strive to control their regulator so that it supplies gas with the least resistance possible. Practice makes perfect!

Types of adjustment wheels and levers. Some regulators do not have both adjustment knobs and levers. Sometimes, the Venturi effect lever is located at the top of the second stage regulator, right in front of the mouthpiece. Some regulators do not have any manipulators. Examine your equipment closely and check what each part is for.

For advanced divers This part will include specific methods for improving the quality of your dives, as indicated in the article titles. Please treat each method as a proposition and not as the only proper solution. Instead of detailed descriptions, you will get abridged versions – it should be sufficient. If it is not so, let me know through the Perfect Diver channels!

This part is intended for experienced divers, who are pretty good at diving. They use several decompression gases for their dives and their average diving times range between 2 and 4 hours.

Ask your instructor for help or conduct several tests together with your partner to learn how to block the free gas flow in the regulator. Prepare an additional cylinder and try to trigger the regulator my pressing the by-pass button next to the Venturi effect lever and adjusting the pressure adjustment knob to the “plus” position. After triggering the regulator, move the Venturi effect lever away from your mouth (to the “minus” position) and the regulator will stop supplying gas. Many beginners are afraid of triggering the regulator and dive with the lever in the “minus” position. It may be compared to driving a car with a secondary brake on; however, not using the Venturi effect lever has much more serious consequences for us – increase in CO2 levels. 1. Our regulators fixed to stage cylinders independently bring down to the ambient pressure level. To do that, they need gas supply from the cylinder – otherwise, they leak and fill with water. When you dive with one or two stage cylinders, you may easily avoid that by levelling the pressure when descending* – you do a modified valve drill.

` During multistage dives, flooding first stage regulators is normal** – it is part of the dive*** (it is impossible to perform the mod-v drill with four to six cylinders on several lanyards). In such a case, you do a mod-v drill a cylinder that will be switched before starting the actual gas switching procedure.

` Replacing the regulator between the cylinders does not pose a problem for its operation. You should replace the entire regulator (first and second stage) and do it in a stable position. It may be a good idea to protect regulators against loss (e.g. by securing it with a double-ender) during replacement. Disassembling regulators may result in the loss of parts.

* you will not flood the regulator when diving at a stable depth, despite the pressure gauge showing “zero”, if you had done a mod-v drill at that depth. ** flooding the first stage regulator will not cause it to freeze up *** that is why regulators used for such dives are serviced much more often, if you dive in salt water

2. In deep diving, regulators do not freeze up. If the gas mixture consists of more than 40% of He, it is impossible for the regulator to freeze up. ` If you dive in shallow but very cold water, I recommend using triox 30/30, which effectively protects against regulator freeze-up.

3. Long oxygen decompression may be counterproductive due to vasoconstriction and, consequently, increased blood pressure. The vasodilation caused by a gas break may be insufficient, so, unlike in the previous part of the article, where I describe methods to lower your CO2 levels, a little exertion here (e.g. by increasing breathing resistance) may prove useful.

I hope that by the time the next issue of Perfect Diver is published, every one of you will have checked and reconfigured your regulators to be able to dive with your head tilted backwards and done a series of dives, leveraging the full potential of your regulator. The next issue will be even more interesting. Come and read the second part of our article on regulators!

WAF

Photo Mariusz Czajka As usual, I would like to invite you to take part in mini-seminars on diving techniques for every proficiency level. We prepared a presentation and practical exercises to help you learn to use each configuration on your regulator so as to minimize the effects of CO2 on your body and make your diving safer. Seminars are held at the Tecline Academy.

https://teclinediving.eu/tecline-academy/#/