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How Scuba Regulators Work

Regulators on the air pressure tank at ambient pressure is reduced for us to breathe underwater. The controller is in two stages, the first of the cylinder pressure is reduced to an intermediate pressure, the second step, usually in the lead in modern equipment, spare time is taken, he further reduced, so that we can breathe at ambient pressure.
Regulators provide air on demand, which means that if the diver is breathing into the regulator open to allow air flow when the diver breathes air, the demand valve is closed and air is discharged into the water.
First stage regulator
The first stage regulator is connected directly to the scuba tank. The connector is a standard A-clamp that fits over the valve at the top of the tank and is secured by a screw yoke, even though some European divers use a DIN connector. DIN offers a secure attachment by screwing directly into the tank valve and can be used with higher pressure than the A-cylinder clamp, but divers with DIN controller can use a converter to convert their equipment to create a U.S. armored diving style.
It is not only the type of connector that may change if the mechanism for detecting changes in pressure to either a piston which acts on the external pressure of the water, or a flexible membrane to a push rod. Both types of control can be either symmetrical or asymmetrical, offset to the former situation, variations in cylinder pressure and thus a greater openness to supply more air to the order.
Finally, some regulators are sealed first stage, which means that instead of water acting directly on the mechanism, it acts on a fluid that transmits pressure to the piston or diaphragm. The advantages are that it reduces the risk of internal corrosion or sediment is reduced to prevent the inside of the first stage and the thermal mechanism, which is important too, at low temperatures to the controller prior to freezing.

The second step
The second stage is the first stage through a pipe, which is usually worn on the right shoulder, attached. It consists of a diaphragm and exhaust valve at the front, back, top to bottom and rear tailpipe.
As with the first step there are different types of second stage regulators - the most common is the downstream valve, where a membrane associated with a lever opens or closes a one-way valve. In the alternative lever opens a valve driver, which in turn opens the main valve, a more complex design that provides more air circulation for less effort. The greater complexity of making both more expensive and difficult to maintain.

Certification

With the increasing popularity of the sport, there were numerous dive centers and certification programs in recent years. In the U.S. alone there are nearly 2000 professional diving centers. The first thing you should do before a program is to test the various centers and find out who of them be the most appropriate for you.

PADI Certification

Open Water Diver Certification:

You must be at least 15 years to receive the Open Water Diver certification. Certifications of the more open water, you can immerse yourself without the presence of the teacher (if the charter does not permit required). There are also Junior Open Water Diver for people 10 to 15 before your certification, it is almost every center that you are in good physical condition recommended. Some even require that you obtain a medical certificate before enrolling in a certification program. You must also know how to swim if you are not necessarily good. However, you should be able to swim 200 meters each shot and be able to swim or walk on water for about 10 minutes.

Diving Centers for certification:

There are many diving centers around which you can teach the basics techniques and skills of diving, but not all of them are absolutely reliable. Try doing a little research before you enroll in a program. See also an agency that provides internationally recognized certification card if you travel a lot.

Some of the organizations diving's most popular and largest certification diving PADI, NAUI, YMCA, Scuba Schools International, and PDIC. These organizations provide some of the best courses and diving instructors are available. But the training method, duration, etc. Teaching can not be equal to all of them. For example, NAUI are often more technical in the classroom than other programs, but can not say better or worse than others. Thus the result of the training and education will ultimately depend on your effort and individual trainers.
Bubble Makers midshipmen, and said, are some popular agencies specializing in the provision of Junior Open Water Diver certification for people 10 to 15

Course:
The duration of a diving certification usually depends on you and your schedule. Basically, it takes about two to three months for full certification, which would cost between $ 175.00 and $ 250.00 and can be accessories such as books, tables and equipment rental, etc. (you must purchase or rent your equipment Diving own) for a party. A certification course includes instruction in general, examinations, practical skills sessions and four open water dives 56. The working class can once a week with weekends more intensive, which will include the reading progressed, while the open water dives usually last two days.
The Scuba Diver allows you to base, 60 to 100 meters below the surface dive, while allowing an advanced diving certification allows you to make deep dives of about 130 meters. Advanced dive certification is more focused on safety, physics, navigation, night diving, diving physiology and dive tables.

Conquering Fear

            We all have to overcome fear at some point in our lives. Fear can be a good thing, think twice about what we can to save our lives, but if too seriously, it can mean that we do not finish what we start, or worse, simply do nothing .
            Diving is like an extreme sport .Finally, try to learn exist in an environment that is not for the human body. Diving can certainly learn to be a challenge. You can not just throw on the gear and swim off into the sunset as beautiful as it sounds. There are some technical devices that work like you who is bulky and cumbersome, but it also is the fact that you are to be under water far longer than you're used to getting used to. Some people find it easy, but if you're one of those who fight without an excessive burden, are you, if you successfully stay the course.
            I think anyone who has dived, had moments where they were afraid, and if they say they do not appear very often or not they are lying! For some people this is the case during the course, but even after 500 dives, there is still potential for something to throw you a curve ball.

There are two important steps to learn how to get your anxiety under control:
1 . Breath.
As the golden rule of diving is never hold your breath, the other golden rule is to overcome fear and to stop, it's something uncontrollable with your breath to calm down. If you run in fear, you will begin to hyperventilate - breath control has a number of things. First, you will slow the heart rate and start making you feel calmer. Second, it gives you something else to focus and distraction is a good thing.

2 . Stop thinking.
This may sound strange, it is also the best way to overcome what you fear. Think from the theme music from Jaws, and always you will not be able to hide from the head and sharks around every corner, think about how difficult it is to help breathe a controller and more, it becomes harder and harder to start thinking that you can not clear the water in the mask, without coming to the surface and suddenly you are not able to.

It must be said that diving is not for everyone. It could be just someone who will never be comfortable under water and it is important to be able to differentiate between the fear of something new and the sport is not easy to achieve good for you. Do not underestimate the importance of not even teachers. If you click on the two missing, or the teacher can not spend time to make you feel good, then it might be interesting to try someone else before you throw in the towel.

An Introduction to Technical Diving

The desire for dives deeper and deeper under the water and led to the development of special gas mixtures. The use of these techniques in diving offers an exciting range of new skills and the marine environment for qualified technical divers to explore.
Pushing the boundaries.
Divers are limited by simple physical laws, (depending on the depth of the dive) at a time under water and a maximum depth overall. Education organizations recommend that divers using compressed air goes no deeper than 130 to 165 feet (40-50 meters). In addition, nitrogen can accumulate dangerously fast in the body, greatly increases the risk of decompression sickness. In addition, increased levels of nitrogen in the blood below 165 ft (50 m) may Leah. i too heavy nitrogen narcosis. The oxygen content of air is also more and more deeply toxic to the nervous system dive.

To extend the dive time and therefore the exploration have been developed in greater depth special blends of gas for which the balance between oxygen and nitrogen has been changed, or that contain new gas to dilute the effects oxygen or nitrogen. The use of these mixtures is known as technical diving, and includes three types of gas mixtures: Nitrox, which allows for longer dive times, and trimix and heliox to reach greater depths.

Extend The Dive Time

Normal air is approximately 21 percent oxygen and 79 percent nitrogen. Nitrox is a gas mixture containing a higher proportion of oxygen and low nitrogen content than usual, so the dive time is longer from the diver's body to store too much nitrogen, and fatigue-free diver after the dive. Nitrox can be mixed in various ratios, from 22 to 50 percent oxygen. But is increased beyond a certain depth of the oxygen in the Nitrox mixture of toxic and can cause seizures. The more oxygen in the mixture, the shallower it will happen for this reason requires that nitrox diving special training, even if the courses are easily accessible to recreational divers.

To Deep

Divers want to get more than 165 feet (50 inches) of travel either heliox or trimix, introducing two of the helium in the breathing mix. Heliox contains only helium and oxygen, while the Trimix is a combination of three gases helium, oxygen, and (mostly) nitrogen. Heliox is used primarily by military and commercial divers, while the Trimix is frequently used by free divers. Both in reducing the probability of nitrogen narcosis, oxygen toxicity, DCS and be successful. Since helium heal six times faster than air does, these mixtures can cause divers to feel very cold. Helium is also rapidly absorbed into the body, as long decompression is required. Want to use these various gas mixtures must be properly trained.

Technical Kit

Diving at extreme depths or in extreme environments such as deep caves, requires special equipment. Divers to carefully analyze their technical equipment, and try to eliminate the weaknesses, there is little room for error during a deep dive technique. Is used to support the extra gas tanks in technical diving, most divers opt for high-lift "wing"-style buoyancy compensation. You choose, high-performance regulators that can handle the task of providing breathing gas at extreme depths. Sophisticated computerized to control use, such as technical gas mixtures metabolized during the dive.

Ear Equalization Basics

Can You Equalize Your Ears ?

Right about now, you are probably wondering if you can equalize your ears. Try this: pinch your nose closed and gently breath out against your pinched nostrils. You should feel something happen in your ears as they equalize. Ear pressure equalization is usually accompanied by a popping/clicking/“poof” sound and a sensation of fullness in the ears. If this technique did not work for you, alternate methods used to equalize the ears when diving are listed below.

What Parts of a Diver's Ear Are Effected by

Pressure ?

To understand how ear equalization works, divers must first learn some basic ear anatomy.

• The Outer Ear is open to the environment and is filled with air (or water) from the surroundings. The outer ear experiences the same pressure as the outside environment.
• The Middle Ear is not open to the environment. In fact, the middle ear is almost completely air-tight. The only way air can move in and out of the middle ear is through a thin tube called the Eustachian tube.
• The Eustachian Tube connects your ears to your nose and throat. When the Eustachian tube is open, air can flow from your nose and throat into your ears. However, the Eustachian tube is normally closed, trapping air in the middle ear.
• The Eardrum is a thin tissue that separates the outer ear and the middle ear.

Why Do Divers Have to Equalize Their Ears ?

Water pressure increases the deeper a diver goes. Since the outer ear is is effected by the pressure of the surrounding environment, the pressure in the outer ear increases as a diver descends. However, the middle ear is sealed so the pressure in the middle ear does not change. If a diver descends without equalizing his ears, the increased pressure in the outer ear relative to the middle ear flexes the eardrum inwards. Ouch! The discomfort felt as the eardrum bends inwards is called a squeeze.
A Diver must equalize the air pressure in his middle ear with the pressure in his outer ear or he risks a ear barotrauma (pressure related injury) or even rupturing his ear drum.

How Do Divers Equalize Their Ears ?

To equalize the air pressure in his middle ear during descent, a diver must manually open his Eustachian tube to allow high pressure air to fill the middle ear. This is easier than it sounds. Divers can equalize their ears using any of the following techniques.

• Valsalva Maneuver
Pinch your nostrils closed and blow gently through your nose.
• Frenzel Maneuver
Preform a very gentle Valsalva maneuver by breathing against pinched nostrils and swallowing at the same time.
• Swallow or Wiggle Your Jaw
While keeping the regulator in your mouth, swallow or wiggle your jaw.

How Often Should Divers Equalize Their Ears on Descent ?

The answer varies from diver to diver. The general rule is that a diver should equalize his ears before he feels pain or discomfort. Most divers equalize their ears every few feet while descending. Keep in mind if a divers ascends a little bit, he will have to re-equalize his ears as he descends again. A diver cannot over-equalize his ears, so when in doubt, equalize!

Do Divers Have to Equalize Their Ears on Ascent ?

Usually, divers do not have to manually equalize their ears as they ascend. As the water pressure decreases on ascent, the pressure in the middle ear becomes greater than the pressure in the outer ear. The extra air pressure usually leaks out the Eustachian tube automatically.
If a diver's ears do not equalize automatically as he is ascending, he may experience discomfort in his ears as the eardrum bends outwards, called a reverse block. A diver experiencing a reverse block may feel discomfort occasionally accompanied by a feeling of dizziness called alternobaric vertigo. Alternobaric vertigo occurs when one ear equalizes automatically on ascent and the other does not.
Reverse blocks are common when the Eustachian tube is inflamed, or when a diver is congested. Keep in mind that a reverse block is caused by too much air pressure in the middle ear, so attempting a Valsalva Maneuver (or similar equalization technique for descents) will only make the problem worse because it adds more air pressure to the already over-full middle ear.

• Toynbee Maneuver (Equalizes Ear Pressure on Ascent)
If you must manually equalize your ears on ascent, try the Toynbee Maneuver. Pinch your nose closed and swallow. This creates a negative pressure and will help to suck extra air pressure out of the middle ear.

What Should a Diver Do If He Has Equalization Problems ?

If a diver has equalization problems, either on ascent or descent, he should immediately establish neutral buoyancy so that he does not descend or ascend inadvertently. Any further depth (and therefore pressure) change could exacerbate the problem. The diver should signal to his buddy that he has a problem with his ears, and attempt one of the following techniques. Remember never to equalize forcefully.

• For Equalization Problems on Descent

1. Take a few seconds to relax and focus on your breathing.
2. Gently try a different equalization technique, such as swallowing
3. Look up to stretch open your Eustachian tubes and gently try to equalize.
4. Ascend a few feet and try to equalize again.
5. If nothing works, slowly ascend to the surface, relax for a few minutes, blow your nose and clear your throat, and then try again.

• For Equalization Problems on Ascent

1. Open your Eustachian tubes by swallowing or wiggling your jaw.
2. Try the Toynbee Maneuver: pinch your nose closed and swallow.
3. Descend a few feet and wait for the pressure to equalize on its own.

Some Medical Conditions Make it Difficult to Equalize:

1. Age: Children have small, flat Eustachian tubes that gradually open as they mature. Kids may find it difficult or impossible to equalize until their Eustachian tubes open fully.
2. Illness: Congestion and inflammation associated with upper respiratory tract infections may block the Eustachian tubes and prevent equalization.
3. Deviated septum: A deviated septum can inhibit proper air flow to the Eustachian tubes.
4. Uncontrolled nasal allergies: Any allergy that causes congestion can make equalization difficult.

Can Divers Take Decongestants to Aid Equalization ?

No. Decongestants will clear out your airways and make it easy to equalize your ears, but they are a bad idea for several reasons.

1. Decongestants wear off: Decongestants and other medicines may be metabolized more quickly while diving. If a decongestant wears off while you are underwater, it is likely you will experience reverse block. While you don't have to go down, you eventually have to go up as your air runs out, and ascending with a reverse block can lead to an ear injury.
2. You are sick: If a diver is sick, his body is in a weakened state and may more likely to get decompression illness .
3. Your chest may also be congested: If your chest is congested, you run the risk of lung-expansion, which occurs when air can not effectively escape the lungs on ascent. This can happen on a molecular scale and it can kill you.
4. Impaired reflexes: if you shouldn't be operating heavy machinery on a medication, it is generally a bad idea to be diving on it.