The choice of scuba. Cinematic sports equipment and the rules of swimming under water What does scuba gear consist of?

translates as "water lungs". The creation of the components of scuba gear occurred gradually. First, the surface air regulator was patented, then it was adapted for scuba use. The first successful underwater breathing apparatus using pure oxygen was invented in 1878. The first scuba gear was created in 1943 by Frenchmen Jacques-Yves Cousteau and Emile Gagnan.

Scuba diving can be one-, two- or three-cylinder with air under pressure of 150-200 atmospheres. Usually cylinders with a capacity of 5 and 7 liters are used, but if necessary, cylinders of 10 and even 14 liters can be used. They have a cylindrical shape with an elongated neck, which is equipped with an internal thread for fastening a nozzle or high pressure pipe. Cylinders are made of aluminum or steel. Steel cylinders must be covered with a protective layer, without which their outer part is subject to corrosion. Zinc is used as such a coating. Steel cylinders are stronger and less buoyant. Cylinders are filled with compressed and filtered air or gas mixture. Modern cylinders have overfill protection. The scuba gear is equipped with a lung machine and straps for attaching to the human body.

All scuba gears are divided into three types according to the type of breathing pattern: with open, semi-closed and closed circuit.

If scuba gear works on the principle of pulsating air supply for breathing (only for inhalation) with exhalation into the water, then this is an open circuit. At the same time, the exhaled air does not mix with the inhaled air and its reuse is excluded, unlike devices with a closed cycle.

In scuba gear closed circuit breathing carbon dioxide is removed from the air exhaled by the diver and oxygen is added as needed. In this case, the same volume of air is used for breathing several times. Using this type of scuba, the diver is less noticeable to the inhabitants of the underwater world and does not frighten them, since there are no bubbles of exhaled air.

At semi-closed scheme part of the exhaled air goes to regeneration, and part goes to the water.

Breathing in an open-type scuba gear is carried out as follows: compressed air enters the lungs through a mouthpiece from a breathing machine, and exhalation is made directly into the water. Air is supplied by a regulator connected to the outlet of the balloon block. From each cylinder, air flows into the regulator in turn through the stopcocks. Using the pressure gauge connected to the regulator, you can make sure that the cylinder is filled with air in accordance with the working pressure, and by stretching your hand back and turning the stopcocks, you can find out how much air you have left in the cylinders.

The second stage of the regulator is a pulmonary (respiratory) automaton, which converts the air leaving the first stage of the regulator to ambient pressure and supplies it to the human respiratory organs in the required amount. Breathing machines are divided into two groups - with flow and counterflow valve mechanism. In most modern scuba tanks, a breathing apparatus with a flow valve mechanism is installed. The valve is opened by the air flow coming from the first foot during inhalation and closes the exhalation tube, and during exhalation - the inhalation tube. Thus, in closed-circuit scuba, the loss of clean air and the inhalation of already used air is prevented.

According to their device, scuba gears are single-stage and two-stage, without separation of air reduction stages and with separation. Nowadays, two-stage automata with separated reduction stages are used.

The main task of an underwater breathing apparatus (scuba gear) is to provide a balanced supply of air to the diver's lungs at a pressure that is equal to the environment. Scuba gear consists of three main parts:

1. Cylinders. High-strength steel tanks into which air is pumped under high pressure. Recently, aluminum alloy cylinders have been used. The pressure in the cylinder is 200 - 300 atm.
2. Pressure regulator. It is a reducer for converting high pressure in a cylinder into low pressure, under which air is supplied to the breathing mask.
3. Accessories: mask, connecting hoses, attachment straps and weight system.
4. Buoyancy compensator. It is a rubber container into which air is pumped depending on the depth of immersion.

Most often refuel with clean dehydrated air. Also used are various breathing mixtures made up of oxygen, nitrogen and helium. They are especially necessary at a large depth of immersion. A special compressor is used to fill the cylinders. It compresses the air to the required pressure and also cleans it of water particles and lubricating oil. The purity of the breathing mixture is the most important condition for safe diving. Multi-stage filters with adsorbents and separators are used. Cylinders are recommended to be stored filled, as then the ingress of foreign substances and water is excluded, which greatly increases the corrosion of the inner surface.

The pressure regulator is the most important part of the diving apparatus. Now they use combined models. They simultaneously perform several functions:

• Reducing the air pressure to the required value, which depends on the depth of the dive.
• Control over the pressure in the cylinder (a pressure gauge is installed on the body).
• Attachment of breathing hoses to the mask. Exhaust valve placement.

The single stage is mounted on the valves of the cylinders on the back. When positioned face down (and this is one of the main positions of the diver), it is 20 - 30 centimeters above the lungs, which makes it difficult to breathe. Therefore, now began to use a two-stage system. The node of the second stage is referred to as a lung machine, and the first - a pressure reducer. The two-stage system has good functionality and is especially used in diving clubs, as it provides comfort.

The regulator reducer is placed as close as possible to the cylinder for safety reasons, since the connection is made by a high pressure line. Sometimes two reducers are used, separate for each cylinder. The pressure in the line from the reducer to the lung machine is 10 - 15 atm. The lung machine is hung on the mask. In particularly critical cases, a backup respiratory system is used. Then the circuits from both cylinders are made completely separate and independent of each other.

Of great importance for safe diving is the subjective control of air consumption. The main device that is used for this is a manometer. Now they do it analog. It is characterized by simplicity and reliability. Digital instruments are not yet widely used, but they make it easier to count the remaining time of the dive. The manometer directly controls the pressure in the cylinder and is connected to it by a flexible high pressure line.

All main parts of the diving apparatus are connected into a single system using various rubber hoses. Straps secure the device on the back. The buoyancy compensator has the form of a vest with a container filled with air. Thanks to the compensator, as you dive into an increasingly dense environment of water, the diver's buoyancy remains unchanged.

Before you start filming underwater, it is absolutely necessary to have a good understanding of the theory and practical exercises in the technique of underwater sports. After the scuba gear, mask, fins and breathing tube become so familiar and natural that you stop feeling them, you can also take on an underwater movie camera.

DIVING SUITABILITY

Speaking of scuba diving, it is immediately necessary to distinguish between swimming and diving with a breathing tube from scuba diving. The first case is simpler and more accessible, but in the second case, the operator, having turned into an amphibious man, gets immeasurably better opportunities for shooting.

Any person with healthy ears and heart is fit for scuba diving. Sometimes two circumstances interfere with the rapid mastery of this art: some hydrophobia, as well as difficulty breathing through the mouth that occurs in some people (when diving, they breathe only through their mouths). These obstacles can be overcome (the first one very easily) by practicing snorkelling. The sight glass of the mask gives a person confidence in the water, as it makes it possible to see the bottom and all surrounding objects. Since the mask also acts as a float, the beginner is quite surprised that he does not sink even when he does not make the slightest movement, and this gives him a feeling of confidence and security (Fig. 16).

Difficulty breathing through the mouth (which is quite rare) is explained. a purely nervous condition caused by the fear of suffocation, since breathing in this case is not quite free. Approximately the same is experienced by some in a gas mask. A few snorkel exercises should dispel the fear. After that, the swimmer will feel good in the water when diving and breathe normally through the scuba mouthpiece. In domestic diving practice, another name for the breathing mouthpiece is common - a mouthpiece. This name comes from the fact that the rubber mouthpiece is inserted into the mouth and held by the teeth and lips.

Snorkel, mask, fins

The breathing tube provides breathing while swimming when the swimmer's face is under water. Moving with the help of fins, he has the ability to view objects in the water through the glass of the mask. If necessary, the swimmer dives for a pause between inhalation and exhalation.

The simplest breathing tube consists of two parts: an aluminum, plastic or rubber (elastic) curved tube and a mouthpiece, i.e., an elastic mouthpiece articulated with the lower end of the tube to hold it in the teeth.

Typically, the length of the tube does not exceed 450 mm with an inner diameter of 15-22 mm and has a volume of 100-200 cm3. The weight of the tube ranges from 80 to 300 g (Fig. 17).

Rice. 17. Valveless breathing tube: 1 - tube; 2 - mouthpiece front shield; 3 - mouthpiece; 4 - "snacks" for holding the mouthpiece with your teeth; 5 - lips; 6 - teeth; 7 - language

The device of the tube is so simple that it is easy to make it yourself.

The simplest snorkel is preferred by experienced divers, by everyone else, and is the main sport type of snorkel.

More complex in design are breathing tubes with automatic ball or float valves that prevent water from entering the tube (Fig. 18). The action of automatic valves is that a light cylindrical ball, or float, emerges and blocks the access of water to the inside of the tube. Such tubes are used by beginners who do not yet have the skill to use a more convenient, simple tube.

There are breathing tubes in combination with a mask. The principle of their device is the same as that of tubes with an automatic valve, but when used, the breath is taken through the nose, since the mouth is outside the mask. Such tubes are less convenient, and we do not recommend them for underwater film enthusiasts.

The importance of breathing tubes in underwater sports cannot be overestimated. In addition to simplicity and ease of use, they make it possible to set your own breathing regimen under various loads, acquire a conditioned reflex in closing the airways when water enters the tube.

The breathing tube must be behind the belt and the scuba diver. It may not be needed on ten, fifteen, or even twenty dives, but on the twenty-first dive, the breathing tube will save his life.

Under water, a scuba diver feels calm and confident. But when he comes to the surface, he is nothing more than a swimmer loaded with heavy equipment. If he emerges far from his base (boat or shore), having used up all the air in his cylinders, and if, in addition, there is a slight wave on the sea, the situation may be threatening. In this case, the diver begins to tire quickly, especially since, due to the equipment, he is not as free in the water as an ordinary swimmer. Therefore, he is forced to use a breathing tube instead of scuba gear, which rises sufficiently above the water. Then the swimmer is not in danger of drowning, and he calmly returns to his base, not fearing that he will be exhausted.

Therefore, one of the basic rules of scuba diving is the obligatory presence of a breathing tube, regardless of whether you are going to dive to a large or shallow depth, close or far from the coast.

The second very essential accessory of a swimmer is the mask (Fig. 19). It serves to protect the eyes from the surrounding water and thereby provides the swimmer with the ability to see in clear water. The separate device for breathing and vision is a reliable guarantee of safety. If the mask falls or fills with water, the swimmer will continue to breathe normally through the mouthpiece. He can either float up, pinching his nose (if the mask was asleep or the glass broke, which has not happened in practice yet), or, if the mask is in place, but filled with water, calmly remove the water.

The device of the mask is simple: it consists of an oval or round viewing glass, a rubber base, a metal tie-down rim and an occipital strap, or headband, which is fixed in the upper part of the face.

A conventional mask has a flat safety glass window that changes the perception of distance and increases the size of objects. This is due to the higher refractive index of water (1.33) compared to air. Therefore, under water, the bottom usually seems closer than it really is. In reality, such an increase in objects does not really matter, since you stop noticing it after the first attempt to swim with a mask.

An increase in objects is felt only when a familiar object (for example, a bottle, a can) enters the field of view.

In order to have a normal image under water, in a number of countries a special corrective mask with two windows is used, in each of which a convex and a concave lens is inserted (Fig. 20). Lenses eliminate distortion of shape, distance and increase the field of view. A corrective mask makes it possible to see life-size objects underwater, but in the air it distances and distorts objects. Therefore, this distortion should be taken into account when entering and exiting the water.

The mask allows you to dive to any depth and swim on the surface. This explains its versatility and widespread use among athletes. The mask, like the breathing tube, is easy to make yourself.

Fins are the third essential element for scuba diving. They serve to increase swimming speed and maneuverability underwater. In addition, fins are extremely energy-saving for the swimmer.

At this time, several dozen varieties of flippers are known, but they all have, in principle, one device and one purpose. However, the degree of elasticity of caresses is the main criterion for assessing their quality and allows all fins to be divided into three types: elastic, normal and rigid.

Practice has established that the efficiency of elastic fins is significantly inferior to normal and even more rigid ones. It is good to use normal fins for long swimming and for long distances, since in this case the swimmer's forces are more advantageously spent.

Athletes prefer rigid fins when swimming for short distances at maximum speed, as well as when it is necessary to increase maneuverability.

In this case, the athlete's strength is most fully spent in a short time.

Well-chosen fins make it easier for the swimmer to maneuver in the water, increase the speed of movement, and free their hands for filming.

SCUBA

The most remarkable quality of scuba gear is that it allows a person to swim underwater at various depths and in any position without any additional adjustment. The device automatically adjusts the amount of air supplied to the lungs depending on the depth of the dive. Thanks to scuba diving, a person under water, as it were, acquires second lungs, specially adapted for breathing in water, and does not feel bound by anything.

The body is freed from the need to be only in an upright position, as it happens on earth. At will, a person can dive deep or float to the surface.

With such equipment available for development and relatively safe, we can talk about its widespread use in underwater filming.

A feature of this apparatus is that it is filled not with oxygen, but with compressed air. Scuba diving uses an open breathing system: the air exhaled by a person, without lingering anywhere, comes out (Fig. 21).

Thus, fresh air is constantly supplied to the human lungs from the cylinders. The use of compressed air completely eliminates the possibility of oxygen starvation, carbon dioxide poisoning or oxygen poisoning. The advantage of scuba gear over other diving apparatus is the ease of construction and operation, as well as readiness for immediate action? immediately after opening the cylinder valves.

How is scuba gear?

Its main parts are: a lung machine, steel cylinders for storing compressed air up to 150-200 atm, two corrugated rubber hoses, a mouthpiece and a system of belts for attaching the device to the body.

The lung machine is the main and most critical part of the apparatus. Its task is to lower the pressure of the air in the cylinders to the pressure of the external environment and supply it to the human lungs in a timely manner and in the required quantity. The lung machine is actuated by the lungs of a person, due to which its work is automatically coordinated with the rhythm of breathing: air is supplied to the lungs only during inhalation, and during exhalation the supply stops. The lung machine is connected to the cylinders and to the mouthpiece by means of two corrugated hoses, one of which is used when inhaling, and the other when exhaling.

The most common domestic scuba gear is the Submariner-1 (factory brand AVM-1), manufactured by the Respirator plant of the Moscow Regional Council of National Economy (Fig. 22).

Rice. 22. General view of the scuba "Submariner-1"

In this apparatus, air compressed up to 150 atm is stored in two cylinders fastened into a cassette with two clamps. The capacity of each cylinder is 7 liters. Thus, the total air supply at full pressure is about 2100 liters.

A two-stage lung machine is attached to the cylinders.

The device is attached to the diver's back with a set of straps - two shoulder, waist and lower, which, when put on, are connected to each other with one easily detachable buckle. The set of equipment for the device includes a mask and a weight belt.

The weight belt is a belt with an easily detachable buckle to which lead weights are attached. The amount of weight can be different (the kit includes 14 weights of 0.5 kg each) and is selected in such a way that the athlete is in a state of neutral (zero) buoyancy or slowly sinks. Usually, weights have to be used only when swimming in wetsuits.

The weight of the "Submariner-1" with filled cylinders is 23.5 kg, and under water - 3.5 kg, i.e. the device pulls the swimmer to the bottom. To avoid this, a piece of styrofoam, a rubber football bladder, or other object lighter than water can be attached to the apparatus. In the modernized "Submarine-1" (factory brand AVM-1M), this drawback is eliminated, and to compensate for the weight, foam plastic is attached to the cylinders in the factory.

The maximum diving depth for scuba diving is 40 m. Diving deeper* is not recommended to avoid possible impairment of vital functions known as nitrogen intoxication. Is this why it's not recommended? dive several times a day and consume more than two cylinders per day.

It is known that the amount of air consumed varies depending on the pressure of the medium: as you dive for every 10 m, it increases by approximately 1 atm. Therefore, the duration of diving depends on the depth of the dive.

On the surface or at a depth of up to 1 m, the average duration of stay under water in the Scuba Diver-1 is practically about 70 minutes, at a depth of 5 m - 50 minutes, at 10 m - 30 minutes, at 20 m - 20 minutes and, finally , at a depth of 40 m - about 3-10 min.

These time norms should not be taken literally, as they depend on the following two factors:
1) on the amount of air absorbed during breathing, which is not the same for different people; many divers, after some training, learn to regulate their breathing and at the same time show miracles of economy, using to the end every cubic centimeter of air;

2) on the number of muscular movements during scuba diving; a stationary or slow moving diver consumes less air than someone who is active in the water or doing hard work.

Schematic diagram of the scuba "Submarine-1" is shown in fig. 23. It consists of two systems: high and low pressure.

The high pressure system includes cylinders, connecting air ducts, a minimum pressure indicator 17 and a pressure gauge 16. The low pressure system starts from the lung machine valve 7 and ends with a mouthpiece through which breathing is performed.

When inhaling through the mouthpiece, a vacuum is created in the chamber of the lung machine. The difference between the outside pressure and the pressure in the chamber of the lung machine causes the membrane 1 to bend down. In this case, the membrane rotates lever 2 clockwise about axis 5. Lever 2 rotates lever 4 about axis 5 counterclockwise. The lever 4, when moving, presses the screw 6 screwed into it onto the valve stem 7 with a rubber cushion. Valve 7 moves away from the seat of the lung machine, and the air, passing from the reducer chamber into the chamber of the lung machine, is throttled to external pressure and enters the respiratory organs through the inhalation hose.

After completion of inhalation, the vacuum in the lung machine chamber stops and membrane 1 stops pressing on levers 2 and 4. Valve 7, under the force of spring 8 and air pressure under the valve, will close the opening of the lung machine seat. The pressure in the submembrane cavity will become equal to the external pressure, and the access of air from the reducer to the lung machine will stop.

Exhalation is carried out through a hose that ends with a petal valve. Air, passing through the slots of the petal, rushes into the supra-membrane space of the pulmonary automaton and then, through the holes in its cover, goes into the water, rising in the form of bubbles to the surface.

Simultaneously with the operation of the lung machine comes into action and the gearbox.

Rice. 23. Scheme of scuba diving "Submariner-1"

Through an open valve, compressed air from the cylinders enters through the high-pressure pipeline system under the reducer valve 9, lifts it and follows into the reducer chamber. In this case, the pressure in the reducer chamber increases. As soon as it reaches a value of 5-7 atm (the so-called set pressure), the membrane 14 bends upward, drags the rod along with it and turns the lever 11 associated with it clockwise around the axis 12. In this case, one shoulder compresses the spring 10, and the other presses through the pusher 13 to the reducer valve 9 and presses it to the seat, thereby stopping the flow of air into the reducer chamber.

This cycle is repeated in accordance with the rhythm of breathing.

In the reducer chamber, and consequently, in front of the lung machine valve, an excess air pressure in relation to the outside air pressure is automatically maintained within 5-7 atm.

To prevent an increase in air pressure in the reducer chamber above the set value, a safety valve 25 is provided, which releases excess pressure to the outside. The safety valve comes into operation when the hermetic seal of the reducer valve 9 to the seat is broken, which can happen both during operation and during storage of the device.

Simultaneously with the supply of compressed air under the reducer valve 9, it also enters the pressure gauge 16 and the minimum pressure indicator 77, which serves to warn the scuba diver about the need to go to the surface. Under water, it is possible to control the air pressure in the cylinders using a manometer (in clear water) or by probing the minimum pressure indicator rod (in muddy water). If the air pressure in the cylinders has dropped to 30 atm and the indicator rod 18, under the action of the spring, takes the extended position with a characteristic click, the scuba diver must go to the surface, since the air in the cylinders remains for several minutes of the apparatus operation. To bring the minimum pressure indicator 17 into working condition, it is necessary to press the stem button 18 to the full and only then open the cylinder valves.

In addition to this method, there are sound indicators of minimum pressure to notify the scuba diver about the need to rise to the surface. Such an indicator in the form of a whistle is used in the scuba gear "Ukraine" produced by the workshops of mountain rescue equipment in the city of Lugansk. This device is also based on the principle of pulmonary-automatic action with an open breathing system. The supply of compressed air up to 200 atm in the scuba "Ukraine" is contained in two cylinders with a capacity of 4 liters each and thus amounts to 1600 liters.

The scheme of scuba "Ukraine" is shown in fig. 24. In one block with a lung machine, a minimum pressure indicator is combined. His work is as follows. When inhaling, compressed air from the cylinders enters the chamber of the lung machine and at the same time under the diaphragm 1 of the minimum pressure indicator. The spring 2 is in the Compressed position, and the stem 3 occupies the maximum height, holding the connecting tube 4 on the platoon.

Rice. 24. Scheme of scuba "Ukraine"

As air is consumed, the pressure in the cylinders, and consequently, on the diaphragm 1, decreases. At the same time, the rod 3 under the influence of the spring 2 goes down and, at a pressure in the cylinders of 35-40 atm, releases the tube 4, which connects the outlet of the lung machine with the whistle 5.

In this position, every breath of the diver will be accompanied by a sound signal - this means that it is time to go to the surface.

CHARGING SCUBA WITH AIR

The device can be charged with air either directly from a high-pressure compressor (150-200 atm) equipped with a filter, or from transport (40-liter) cylinders, previously pumped through a filter. Since a special compressor has not yet been created for underwater sports, in practice a field carbon dioxide charging station (FCS) is used to charge scuba cylinders. This is a relatively bulky portable compressor unit with an AK-150 high-pressure compressor (Fig. 25). With such a compressor unit, it is possible to charge the Scuba Diver-1 with two cylinders with a capacity of 7 liters each up to 150 atm in 50-60 minutes with air.

It is expedient to charge transport cylinders with compressed air from high-pressure compressors of higher productivity. For this purpose, compressor stations AKS-2 or AKS-8 can be used, which are towed by a truck on a special two-axle trailer.

The scuba cylinders are charged with air from transport cylinders according to the scheme shown in fig. 26. In this case, three transport cylinders are usually used in order to make fuller use of the air contained in them.

Transport cylinders charged with air up to 150 atmu are connected with spiral tubes to an oxygen pump of the KN type, which, in turn, is connected to a filter, in this case OKN-1.

After the circuit is mounted and tested, for charging it is necessary to open the valves on the cylinders of the apparatus, the first transport cylinder, the compressor star and the filter outlet star. In this case, the air in the transport cylinder at a pressure of 150 atm, after passing through the compressor, goes through the filter coil-refrigerator to the dehumidifier, then to the adsorber and ceramic filter. After the ceramic filter, the air enters the filled cylinders of the apparatus through the outlet star until the pressure in the entire system is equalized. The onset of this moment must be monitored by the pressure gauge on the compressor star and filter star. The cessation of bypass air hiss is also a sign that the pressure in the cylinders of the device has become the same as the pressure in the transport cylinders and will be below 150 atm. The increase in air pressure in scuba cylinders up to 150 atm is carried out by an oxygen compressor of the KN type or by a PZUS unit.

It should be noted that with the help of a compressor of the KH type, it is possible to increase the pressure by no more than two times in comparison with the pressure remaining in the transport cylinder.

If it was not possible to bring the scuba pressure up to 150 atm from the first transport cylinder, you should switch to the second transport cylinder, and then to the third. In this case, transport cylinders with high pressure are used last. After the pressure in the transport cylinders has decreased so much that it makes no sense to carry out further pumping from them, you need to replace them with full ones. By the end of charging, scuba cylinders heat up somewhat, but after a while they cool down, as a result of which the pressure in them decreases by about 10%.

Subsequently, if necessary, the cylinders of the apparatus can be recharged to a full pressure of 150 atm.

To clean the air from mechanical impurities, water and oil, an oil separator is provided on the compressor unit. It is a steel cylinder with a drain valve.

The principle of operation of the oil separator is as follows: air, entering the oil separator bottle, changes its direction, as a result of which oil particles and other particles contained in the air settle to the bottom of the bottle and, as they accumulate, are removed through the tap. The purified air exits through the opposite fitting.

In addition to such a filter, an activated carbon filter is needed to purify the air from foreign gases.

It should be remembered that scuba cylinders must be filled with absolutely clean air, that is, free from any impurities (carbon oxides, lubricating oil vapors, their oxidation products, foul-smelling substances, etc.).

The most dangerous is the content of carbon monoxide (carbon monoxide) in the air, which is found in large quantities in the exhaust gases of engines that drive the compressor. The presence of even a small amount of carbon monoxide in the air can cause swimmer poisoning. Therefore, air quality should be given special attention.

To purify air from impurities, a portable filter OKN-1 is successfully used, designed to purify and dry oxygen from moisture (Fig. 27).

To do this, alumina (drying agent) in the filter adsorber is replaced with ordinary activated carbon, which is used in gas masks. The OKN-1 unit has dimensions of 480x500x240 mm and consists of a dehumidifier, an adsorber, a ceramic filter and an output star.

Moisture Separator is designed to release air from dripping moisture. It works on the same principle as the PZUS oil separator.

The adsorber serves to purify the air from gases and is a small-capacity cylinder4 filled with activated carbon.

The ceramic filter is used to purify the air from activated carbon dust. Its body is made in the form of a glass into which a ceramic cylinder is inserted.

The OKN-1 filter reliably cleans the air from harmful impurities, except for carbon monoxide.

Some athletes also successfully use a homemade filter (Fig. 28).

Rice. 28. Scheme and dimensions of homemade

filters: 1 - activated carbon; 2 - adsorber; 3 - mesh

AUXILIARY EQUIPMENT

A handheld depth gauge is required when diving to great depths or when the dive site is completely unfamiliar. It is very important that the depth gauge has divisions over 40 m. If the divisions end at 40 m, then in this case it is not clear whether you have dived 40 m or much deeper.

There are two types of depth gauges: mechanical and pneumatic. A mechanical depth gauge is similar in design to a conventional pressure gauge and is based on the principle of water pressure in a curved tube of the instrument connected to a manometric needle.

The pneumatic depth gauge is based on the principle of elasticity and incompressibility of water. Water, entering the narrow channel (capillary) of the depth gauge, compresses the air in it in proportion to the depth of immersion. The border of air and water stands out well against the black background of the scale and shows the depth in meters.

The watch is necessary for a swimmer, as the subjective sensations of time under water are different from usual ones - time goes faster under water. In addition, the watch helps to determine the time spent under water and the time before rising to the surface. In addition to specially made underwater watches, ordinary wristwatches enclosed in a sealed case are used for diving.

The knife is not a weapon of defense, since, according to veterans of underwater sports, not a single sea creature attacks a person, but just in case, it is necessary to have it. A knife is needed, for example, in order to quickly cut off a tangled signal end, a cable or a fishing net that a swimmer can fall into, as well as for many other unforeseen accidents under water.

The knife can be floating. Such a knife is convenient for a diver with a mask, who, in case of loss, can easily find it on the surface of the water. But for a scuba diver, this is completely unprofitable, since when a knife floats to the surface, you need to follow it and then dive again. And for a diver, such frequent changes in pressure are harmful.

Immersion suit serves to protect the swimmer's body from the effects of the surrounding aquatic environment, mainly from low temperatures. In the southern seas at the height of summer, you can briefly dive without a protective suit even to 40 m.

But already at a depth of 20 m, the cold is rather difficult to bear, especially for thin people. And despite the fact that protective clothing to a certain extent restricts the movement of an athlete, it significantly lengthens the season of stay under water in the southern reservoirs and ensures immersion in the northern reservoirs at a water temperature of +6 ... + 8 °. To do this, a set of warm (woolen) underwear, fur socks, a woolen hat and gloves are usually put on under the wetsuit.

The main requirements for protective clothing are: reliable isolation of the body from water cooling; freedom of action under water of the arms, legs and body; ease of dressing and undressing; the absence of coarse seams, fasteners, buttons and other details that can cause abrasions of the body when moving underwater; small weight and volume.

The athlete must wear thermal protective clothing that strictly corresponds to his height. Wetsuits that restrict movement or are too spacious should not be worn, as air will be trapped in their folds, which will make it difficult to go to depth.

The correct fit of the suit determines the success of the dive.

Known suits made of sponge rubber and worn on the naked body. Although they are not waterproof, water does not enter the suit or only a small amount does.

Some costumes are made up of two pieces; others take the form of long or short sleeved jumpsuits with zippered trousers. These costumes are easy to put on yourself, without outside help.

Good waterproof suits made of thin rubber (Fig. 29), under which they put on warm underwear. The suit may consist of a shirt and trousers, connected at the waist, or be a one-piece jumpsuit with an elastic collar through which you have to get into the suit. Such impervious suits are very good protective equipment, but they are pressure sensitive and can squeeze the swimmer unpleasantly at depth.

VEHICLES UNDERWATER

An underwater aquaplane (underwater plane) is a light board 60-70 cm wide and 20-25 cm long with a handle, which the athlete holds while in a horizontal position. An underwater aquaplane is towed by a boat (Fig. 30).

An underwater aquaplane is both a rudder and a rudder. Starting from the minimum speed of the boat and ending with 4-5 km / h, a swimmer, when moving behind a hydroplane, can develop strength, agility and orientation under water. By attaching a movie camera to the aquaplane and pulling out the control stick, the underwater swimmer will be able to shoot in an influx.

Underwater sleds are used to tow a scuba diver with a movie camera along the bottom, which has a flat relief. In order to avoid sharp shaking, the sled must be massive enough.

An underwater bicycle (aquaped) is used to move an athlete under water. It is a comfortable sports apparatus and has a buoyancy close to zero. Two propellers with a diameter of about 500 mm, rotating in different directions, or one propeller with a diameter of 700 mm is driven by pedaling. On fig. 31 shows one of these devices.

The underwater scooter among other means of transportation under water has become the most widespread. In appearance, it resembles a small torpedo with one or two propellers driven by an electric motor. Batteries serve as a power source. Propellers can be located both in the stern and in the bow of the scooter with a corresponding change in the direction of rotation. The swimmer holds on to the frame in the stern and by turning his body, and especially his legs with fins, gives the scooter the desired direction of movement. The scooter can carry film equipment, as well as underwater lights.

In this sense, the underwater scooter designed by the cameraman A.F. Leontovich is interesting (Fig. 32 and 33). The scooter has a length of 235 cm, a diameter of 40 cm and a weight of 150 kg. Its underwater speed is from 2 to 6 km/h. Motor power 800 watts. The power source is a dual block of silver-zinc accumulators STs-45, which provides a total capacity of 90 Ah. The tightness of the housing at the exit of the propeller shaft is provided by stuffing box seals. The design uses standard ball bearings. The speed switch has five positions and is brought out in the form of a lever on a common handle. Case material - steel. The scooter has a negative buoyancy of about 200-300g. To ensure an emergency ascent, a safety weight is used, which is separated using a handle.

One of the following equipment can be attached to the scooter: a) a searchlight for search work or for illumination when filming with a movie camera from another scooter; b) film cameras "Konvas-avtomat" with 60 cassettes; c) a container with accumulators and two lighting lamps with their inclusion brought to a common control knob. A flat mirror can be mounted in the bow of the scooter for passing through.

Abroad, several modifications of the scooter are known, named after its designer (Rebikov's film torpedo - Fig. 34), and a number of designs of large scooters capable of carrying several swimmers in addition to film equipment.

Underwater car (akvakeb) - midget sports submarine with a waterproof hull. Its crew is in underwater sports equipment. An underwater car allows you to move at speeds up to 3-5 km / h with a pedal drive and up to 7 km / h with an electric motor. All control of this unit is located on the steering wheel. The necessary stability and buoyancy of an underwater vehicle is achieved using solid ballast. The swimmer's head is protected from counter water resistance by a folding plexiglass shield (Fig. 35).

Floating base - this is how the operator F. A. Leontovich called another design, which he created together with a team of designers led by engineer D. M. Brylin.

In appearance, the floating base resembles a double boat - a catamaran (Fig. 36) and consists of two streamlined aluminum pontoons, between which there is a cargo area. To ensure unsinkability, the pontoons are divided into sealed compartments.

The dimensions of the floating base are: length 5 m, width 3 m, pontoon height 65 cm, draft 25 cm. The total weight of the base is 150 kg, the carrying capacity is about 2 tons. The Moskva motor is suspended from the base platform. The floating base has a ladder for descending the scuba diver into the water, as well as a suspended underwater platform from which the survey is made. To raise and lower the camera overboard, the base is equipped with a special lifting boom.

BASIC RULES FOR SWIMMING UNDERWATER

The ability of a cameraman underwater is largely determined by his equipment.

With a snorkel, mask and fins, the swimmer can shoot down while moving on the surface of the water.

A cameraman equipped with scuba gear can stay under water for a long time and swim in any direction. Equipped with weights for stability, it can move on the ground.

How to put on equipment? Lightly wipe the mask glasses from the inside. Then rinse the mask in water and put it on. The fins must first be moistened so that they can be easily put on the feet. If you are wearing wetsuits, wet the inside of the fins with soapy water. Soapy water will also help with pulling the tight rubber cuffs of the wetsuit over your arms.

Put on the wetsuit slowly, trying to avoid the formation of wrinkles and cavities with air.

Scuba gear on the back should be fastened tightly, without sagging, the straps should be well tightened. The presence of the lower (breast) strap during swimming is mandatory, as it reliably holds the device from distortions.

Descent into the water. To descend into the water, it is best to have a convenient portable ladder (ladder), which could be used both from the pier and from the side of the boat. However, you often have to do without a ladder.

In any case, it is not safe to jump into the water, because when hitting the water, the cylinders can move, and the diver risks being hit by a lung machine in the back of the head. In addition, during a sharp entry into the water, the mask can be shifted from the face.

When descending from an open boat, sit on board with your back to the water, tilt your head to your bent knees (i.e., curl up) and gently tip back with your hands on your mask. This fast and safe way of diving has been proven in many underwater expeditions. Plunging from a pier or from a steep bank, you should do otherwise. Sit facing the water, dangle your legs, and then turn around, transfer your weight to both hands and lower yourself into the water as smoothly as possible.

Don't forget to put a mouthpiece in your mouth before diving into the water. Many beginners forget to do this. If you went into the water, forgetting about the mouthpiece, do not be alarmed. Staying on the surface, remove water from the corrugated tubes by vigorously blowing air into the mouthpiece.

No matter how many swimmers will accompany you in the water, someone must always remain on the shore or in the boat as a belayer. It is he who must pass you an underwater movie camera or illuminator into the water.

Take the equipment only after you are in the water, make sure that everything is in order and the scuba gear is working properly. Before the start of systematic dives, the group should distribute all scuba gear for each diver in order to properly adjust, care for and know the features of each device.

If the camera has removable planes - wings and under water you will have to move at high speed in tow (behind an underwater aquaplane or towing vehicle, behind a fishing trawl, etc.), then the wings should be removed in advance, since at the slightest angle of inclination of the camera they will create large hydrodynamic resistance, the force of which the device will twist out of the hands. For work at high speed (up to 6 km/h), cinema cameras enclosed in streamlined spherical boxes, mounted on a towing vehicle before filming, are convenient.

Towing a scuba diver in ordinary equipment at a speed of more than 6 km/h is not recommended, since the increased resistance of the water environment makes it impossible to control the underwater movie camera, pulls the mouthpiece out of the mouth, squeezes the corrugated breathing tubes, or simply rips the swimmer off the aquaplan or trawl.

Movement under water. You don't have to be a good swimmer to move underwater. A mask, fins, and even more so aqualung give an extraordinary feeling of safety in the water, and a person feels like a fish. To move around, a slow movement of the legs in a crawl style is enough.

Swimming with a mask on the surface and breathing through a tube, you should carefully observe what is happening in the water. As soon as something interesting appears in the field of view, you need to pick up speed, while breathing quickly and very deeply, so that the blood is saturated with oxygen. Then, during one of the exhalations, which should not be done to the end (it is necessary to leave a little air in the lungs in order to blow out the water that has fallen into the tube when ascending), you need to dive head down, continuing to work with your feet. In this case, you need to try to make gentle movements and shake the water as little as possible.

By training, you can bring the diving depth to 7-8 m. You should not go deeper without scuba gear.

When scuba diving, movements should also be slow. Remember that you are inhaling and exhaling through the same small hole in the mouthpiece. Therefore, it is necessary to avoid a sharp transition to rapid breathing, because it can lead to suffocation. Moreover, you should train - to remain motionless underwater for as long as possible, which is necessary to improve filming conditions.

It is desirable that the film camera in the water has zero buoyancy. In this case, it will be quite easy to manage it. However, small deviations in one direction or another do not matter much.

For shooting underwater, it is best to look for places with a rocky bottom, as they are the most expressive and the water in them is more transparent.

When you are exploring a sunken ship or a cramped underwater cave with a movie camera, be aware of the presence of corrugated breathing tubes that are located behind your head. Sharp contact with sharp protruding parts can damage them.

Before entering any narrow passage, it must be carefully examined. Such surveys should be done at least together.

Exit from the water. First, pass a movie camera on board the boat or into the hands of a comrade standing on the gangway. Then, having previously removed from the belt and passed the breathing tube, remove the scuba, holding the mouthpiece in your mouth. Fins do not need to be removed, they make it easier to get out of the water. The mask is removed last.

The main problem under water is that a person has nothing to breathe there! That is why all inventions related to underwater equipment were primarily devoted to ensuring free breathing.

The evolution of thought

The evolution of underwater breathing equipment is quite interesting and fully reflects the general course of human thought. The first thing that comes to mind is that if there is no air under water, it must be supplied there. The easiest way to do this is with a breathing tube, one end of which is above the water. However, not all so simple! If you have ever tried to dive, trying to breathe through a long tube or hose, then you know that the human lungs are unable to overcome the water pressure and take a breath already at a depth of 1-1.5 m.
Therefore, this method is suitable only for swimming on the surface, and many of our readers have probably used it more than once, snorkeling. The next idea - to breathe air at a pressure equal to the pressure of water, led to the invention of a diving bell. It was proposed by Guglielmo de Loreno in 1530. The design of the bell was very simple - a hollow barrel without a bottom, immersed with an open end in water. The pressure in such a bell due to the open end of the barrel and, consequently, the movable air-water boundary, is equal to the external water pressure at a given depth. Working underwater, you can inhale from the barrel from time to time without floating to the surface. One bad thing - the air in the barrel quickly ends.

Of course, the air supply can be replenished. By supplying air to the bell from the surface using a pump, you can significantly extend the stay of a person under water. Of course, this will require the use of an air pump (and the deeper we go, the more powerful the pump must be). However, working (or simply observing the underwater world) is still not very convenient: the diver remains rather rigidly tied to the surface with a hose and a bell and is able to “break away” from them only for the duration of holding his breath.

I carry everything with me

Alas, this problem can only be overcome with the help of self-contained breathing apparatus. In English, there is a special abbreviation for such devices - SCUBA (Self-contained Breathing Underwater Apparatus). The first such apparatus was proposed in 1825 by the Englishman William James. The device consisted of a rigid cylinder in the form of a belt around the diver's waist, filled with air at a pressure of about 30 atmospheres, and a breathing hose connecting the cylinder to a diving helmet. It was inconvenient: the air was constantly supplied to the helmet and due to this (and the low pressure in the tank) it quickly ended.

To overcome this shortcoming, it is necessary to supply breathing air only at the moment of inhalation. This is done using diaphragm-operated valves that respond to the vacuum created by the lungs. This is exactly how the Aerofor device was designed, invented in 1865 by the Frenchmen Benoit Ruqueirol and Auguste Deneyrouz. Their design was a steel cylinder with air under a pressure of 20–25 atmospheres horizontally located on the back of a diver, connected through a pressure reducing valve to a mouthpiece. The membrane pressure reducing valve supplied air only at the moment of inhalation at a pressure equal to the water pressure.

Aerofor was not completely autonomous: the cylinder was connected by a hose through which air was supplied to the surface, but if necessary, the diver could be disconnected for a short time. Aerofor is the forerunner of modern open-cycle breathing equipment (a diver inhales air from a cylinder, exhales into water) for diving. It was used for several years by the French (and not only) navy, and even in 1870 it was mentioned in Jules Verne's book Twenty Thousand Leagues Under the Sea.

There was only one step left for the Aerofor apparatus to its modern form - this is a step towards a supply of high-pressure air. And this step has been taken. But “one step forward, two steps back” - in 1933, the captain of the French navy, Yves Le Prior, modified the Rouquerol-Deneurose apparatus, combining a manual valve with a high-pressure cylinder (100 atmospheres). This made it possible to obtain a longer autonomy time, but the control was extremely inconvenient - when inhaling, the valve was opened manually, while exhalation was made into the mask (through the nose).

And finally, in 1943, Jacques-Yves Cousteau and Emile Gagnan put all the ideas together and give the breathing apparatus the form in which it has come down to us. They connect two cylinders with air (100-150 atmospheres), a special step-down gas reducer and a valve that supplies air under pressure exactly equal to the pressure of the external environment, and only at the moment of inhalation. The Ruqueirol-Deneirouz regulator, which was 78 years ahead of the design of Cousteau and Gagnan, was forgotten for unknown reasons.

Cousteau and Ganyan decided to name their apparatus "Aqua Lung", that is, "Underwater lungs". It was under this name that he became known to the whole world. The word "scuba" has become a household word and entered many languages ​​of the world as a synonym for underwater breathing apparatus.

Modern scuba

Let's take a closer look at how modern scuba gear works. Despite the fact that quite a few years have passed since 1943, modern breathing apparatuses are not far from their ancestor - the Cousteau-Ganyan scuba gear. Yes, of course, technologies have changed, new materials have appeared, but the principles of work have remained absolutely the same.

The main components of the breathing apparatus are a cylinder with air under high (200–300 atmospheres) pressure and a two-stage gearbox.

What is a reducer for?

The fact is that it is simply dangerous to supply air for breathing directly from a cylinder under a pressure of 200 atmospheres: the lungs will not withstand such pressure. Therefore, a special reducing (pressure-reducing) valve is attached to the cylinder. Its first stage reduces the pressure to 6-15 atmospheres (depending on the design and model).

The second stage, usually called the regulator (or lung machine), performs two important tasks. The first is to supply air at a pressure that exactly matches the pressure of the water at any depth. This allows the diver to breathe at any depth without any effort or discomfort.

The second task of the regulator is to supply breathing air only at the moment of inhalation (this allows you to spend air much more economically). At the moment of inhalation, the human lungs create a vacuum, a special membrane-controlled valve reacts to this and opens the air supply.

Exhalation occurs through poppet membrane valves directly into the water. Thus, the air is used only once. Therefore, sometimes scuba is called an open circuit breathing system.

As you can see, the design of the scuba gear is very simple and therefore reliable. Ease of manufacture and maintenance and reliability have ensured many years of scuba success. It was with scuba gear that the real era of exploration of the deep sea began.

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The business associated with such an exciting activity as scuba diving is quite a profitable business. In this article, we suggest that you familiarize yourself with the variety of diving equipment that you will need when opening your own diving school or diving company.

• Variety of wetsuits
• Mask and fins
• Types of scuba gear

The basic scuba equipment is the No. 1 diving set, consisting of three items: fins, mask and snorkel. You can also add a wetsuit with waist weights for a comfortable swim.

A complete set of underwater diving equipment includes:

• wetsuit, fins, mask;
• buoyancy compensator;
• weight belt;
• scuba (rebreather) - a cylinder filled with air or an air mixture, a regulator;
• gloves, boots, helmet;
• depth gauge, underwater watch or a computer that combines all these functions.

Additionally, a flashlight, coil, tow, compass, snorkel, etc. can be used.

Variety of wetsuits

A wetsuit is an integral part of diving equipment, provides thermal insulation, protects the swimmer from the negative effects of the external environment (animal bites, cuts, abrasions).

Required suit thickness

1. Tight Bodyskin- when immersed in warm waters, does not restrict movement, light. Made from stretchy lycra, nylon in vibrant colors. The disadvantage is that it wears out quickly.

2. Drysuit for diving - in cold water with putting on warm underwear underneath. Made from various materials: nylon trilaminate, butyl rubber, nylon or vulcanized rubber.

3. Wetsuit elastic, as it is made of neoprene, easy to put on and take off. The density of the fabric and the style of the cut are selected depending on the expected conditions of the water area. In it, the process of heat loss slows down due to a thin layer of water that heats up from the body. It is applied in warm reservoirs. The tighter the wetsuit fits, the warmer it is.

Aquasphere Aquaskins Dimension Chart

What to consider when choosing equipment

Mask and fins

Mask - equipment for eye protection, ensuring clear visibility under water, breathing through the nose.

Fins provide a smooth movement of the diver under water fins made of rubber or plastic.

Open heel fins and a tightening belt are appropriate for cold water. Special shoes are worn under these fins. The disadvantage is that the straps can rub the heels, the legs are not completely protected.

Closed heel fins do not need to put on additional shoes. With the right size and fit, they are affordable and comfortable.

Watch a video about choosing a mask

Types of scuba gear

Scuba gear is diving equipment that allows you to breathe underwater for a long period of time. Provides supply of compressed air or breathing mixture. The minimum equipment for scuba gear, which allows you to breathe underwater, is a cylinder plus a regulator.

There are two main types of scuba gear:

1. open circuit scuba– the inhaled air is not reused and is discharged into the water. The equipment is portable and convenient to use in recreational diving, cheap. The disadvantage is the impossibility of diving for a long time and considerable depth.
2. Scuba with a closed circuit, or a rebreather - the air is used several times as it circulates as it passes through the system. Cons: Expensive, difficult to use. This is the underwater equipment of professional divers.

Regulator- a piece of diving equipment that lowers the pressure in the cylinder to ambient pressure, and regulates air flow when inhaling and exhaling. The regulator supplies gas to the diver for breathing.

diving cylinders

This is a part of a cylindrical scuba gear used for storing, transporting gas or a mixture of gases under high pressure:

• Standard - 200 bar;
• Low - 150-180 bar;
• High - 200-300 bar.

The greater the pressure, the thicker the walls of the cylinder, which are usually made of aluminum or steel.

Aluminum cylinders wear out faster and are subject to mechanical stress. Steel - rust from the inside.

Indicators of empty and filled cylinders in water, on land

The composition of the balloon includes:

• Shut-off valve - a part that tightly connects the regulator and the cylinder, regulates the flow of gas supply;
• Y-shaped shut-off valve is a valve for two pairs of outlets and fans for connecting the main, as well as a spare regulator;
• The rubber o-ring is a hermetic connection between the shut-off valve and the regulator.

Types of recreational diving cylinders:

• The main one - with a capacity, usually from 10 to 18 liters;
• Spare - emergency air reserve, volume from 0.4 to 1 liter;
• A balloon pony is a small reserve.

Varieties of buoyancy compensators

Buoyancy compensator (BCD)- equipment used to control buoyancy during a dive or ascent by adding or releasing a certain amount of air from a special chamber.

Winged compensator- completely located on the back. Effective for underwater shooting, technical diving. The advantage of this equipment is that the front of the body is free.

Compensator in the form of a vest allows you to achieve buoyancy with a volume of 25 liters. Doesn't restrict movement.

Lightweight and affordable equipment is adjustable compensator buoyancy volume up to 15 liters. It has one inconvenience - fastening around the neck, between the legs.

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Scuba gear is a modern device for deep diving. It allows the diver to breathe underwater without being dependent on the air supply from the ship. The scuba diver carries his own supply of air with him attached to his back. He is a free diver. The compressed air supply is contained in one (or more) steel scuba cylinders. A tube extends from the valve leading to the mouth. It is made in such a way that the diver can hold it with his teeth. The nose is covered with a mask, and the scuba diver breathes through one mouth. With a scuba gear on his back and a special heavy belt to keep him underwater, a person can swim almost as freely as a fish.

When swimming, large flippers on the legs are used to do without the help of the hands being freed, so as to hold the camera or harpoon. If you do not dive to great depths, the scuba diver can stay under water for half an hour or more. But even the most modern scuba gear does not allow a person to go deeper than a hundred meters. At this depth, the gravity of the water column exerts a pressure ten times greater than at the surface. The air in the cylinders is consumed ten times faster, so that even very large cylinders last only a few minutes.

There is another problem associated with diving to very great depths. Compressed air in cylinders, like atmospheric air, consists of four-fifths of nitrogen and only one-fifth of oxygen. We need oxygen to sustain life. Normally, the nitrogen we breathe in is immediately breathed out. But under conditions of increasing air pressure, part of the nitrogen dissolves in the blood and tissues.

When a scuba diver ascends, nitrogen must be removed from his blood and tissues. If it cannot leave the body quickly enough through the lungs, it begins to turn into small bubbles in the body. The bubbles pinch the nerves and clog the blood vessels, and the scuba diver develops decompression sickness, accompanied by terrible pain. As a result of severe cases of decompression sickness, a person can die or remain disabled for life. That is why the scuba diver must rise to the surface very slowly if he was at a depth of sixty to one hundred meters. During the ascent, he must make frequent stops.

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The main task of an underwater breathing apparatus (scuba gear) is to provide a balanced supply of air to the diver's lungs at a pressure that is equal to the environment. Scuba gear consists of three main parts:

1. Cylinders. High-strength steel tanks into which air is pumped under high pressure. Recently, aluminum alloy cylinders have been used. The pressure in the cylinder is 200 - 300 atm.
2. Pressure regulator. It is a reducer for converting high pressure in a cylinder into low pressure, under which air is supplied to the breathing mask.
3. Accessories: mask, connecting hoses, attachment straps and weight system.
4. Buoyancy compensator. It is a rubber container into which air is pumped depending on the depth of immersion.

Often diving cylinders filled with clean dehydrated air. Also used are various breathing mixtures made up of oxygen, nitrogen and helium. They are especially necessary at a large depth of immersion. A special compressor is used to fill the cylinders. It compresses the air to the required pressure and also cleans it of water particles and lubricating oil. The purity of the breathing mixture is the most important condition for safe diving. Multi-stage filters with adsorbents and separators are used. Cylinders are recommended to be stored filled, as then the ingress of foreign substances and water is excluded, which greatly increases the corrosion of the inner surface.

The pressure regulator is the most important part of the diving apparatus. Now they use combined models. They simultaneously perform several functions:

• Reducing the air pressure to the required value, which depends on the depth of the dive.
• Control over the pressure in the cylinder (a pressure gauge is installed on the body).
• Attachment of breathing hoses to the mask. Exhaust valve placement.

single stage diving regulator mounted on the valves of the cylinders on the back. When positioned face down (and this is one of the main positions of the diver), it is 20 - 30 centimeters above the lungs, which makes it difficult to breathe. Therefore, now began to use a two-stage system. The node of the second stage is referred to as a lung machine, and the first - a pressure reducer. The two-stage system has good functionality and is especially used in diving clubs, as it provides comfort.

The regulator reducer is placed as close as possible to the cylinder for safety reasons, since the connection is made by a high pressure line. Sometimes two reducers are used, separate for each cylinder. The pressure in the line from the reducer to the lung machine is 10 - 15 atm. The lung machine is hung on the mask. In particularly critical cases, a backup respiratory system is used. Then the circuits from both cylinders are made completely separate and independent of each other.

Of great importance for safe diving is the subjective control of air consumption. The main device that is used for this is a manometer. Now diving gauges do it analog. It is characterized by simplicity and reliability. Digital instruments are not yet widely used, but they make it easier to count the remaining time of the dive. The manometer directly controls the pressure in the cylinder and is connected to it by a flexible high pressure line.

All main parts of the diving apparatus are connected into a single system using various rubber hoses. Straps secure the device on the back. The buoyancy compensator has the form of a vest with a container filled with air. Thanks to the compensator, as you dive into an increasingly dense environment of water, the diver's buoyancy remains unchanged.

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Human dependence on technology

Those who wondered how to make a homemade scuba gear should remember that any human activity that is not related to the use of any instruments, equipment or other equipment makes one rely only on one's own luck or the help of a friend. These include, for example, swimming. The use of technology by a person - a car or scuba gear - multiplies his capabilities many times over. But in proportion to the complexity of technology, the dependence of a person on it also increases.

A diver equipped with a “mask, fins, snorkel” set finds himself in an unpleasant situation when he loses any of his equipment underwater. But a scuba diver finds himself in a much more difficult situation if the air supply suddenly stops underwater. This can happen at a depth from which it is impossible to ascend in one breath. Bulky scuba gear reduces mobility and increases water resistance. A similar emergency can occur under ice or in a cave. Submariners must pay great attention to the equipment used. This is especially true for those who decide to make a homemade scuba gear.

About the complexity of the issue

Modern scuba diving equipment is focused on his comfort and safety. All nodes and elements of equipment must be thought out to the smallest detail. Specialists have developed rules for the use of equipment, which are strongly not recommended to be violated. A novice amateur who encounters the slightest difficulty in operating the equipment should seek the advice of his trainer, as trouble-free use of the equipment is the key to safe diving.

Scuba is a rather complex device. Experts assure that it is quite difficult to create a homemade scuba gear at home. To do this, you must have the appropriate knowledge and be able to work on good turning equipment. Those who are interested in the question of how to make a homemade scuba gear with their own hands should learn as much as possible about this device.

Story

The word "aqualung" in translation means "water lungs". History shows that the apparatus was created gradually. The first to patent the surface air regulator and adapted it for scuba use. In 1878, an underwater breathing apparatus was invented. It used pure oxygen. In 1943, the first scuba gear was created. Its authors were the French Emile Gagnan and Jacques-Yves Cousteau.

Device

Those who decide to create a homemade scuba gear should know that this device consists of 3 main parts and several additional devices:

• Balloon. Usually one or two containers with a compressed respiratory mixture are used. Each container holds 7 - 18 liters.
• Regulator. Consists of a reducer and lung machine. The scuba gear may contain one or more gears.
• Buoyancy compressor. An inflatable vest, the special purpose of which is the regulation of the diving depth.
• pressure gauge, equipped with a signal that is triggered when the air pressure reaches 30 atmospheres.

Peculiarities

Those wishing to create a homemade scuba gear need to know about the features of its components.

• The high-pressure cylinder, which is part of the scuba gear, is a reservoir for storing air. The working pressure in it is 150 atmospheres. A standard cylinder with a capacity of 7 liters at this pressure holds 1050 liters of air.
• One-, two- or three-balloon scuba gears are used. Usually the capacity of the cylinders is 5 and 7 liters, but if necessary, 10-, 14-liter cylinders are used.
• The shape of the cylinders is cylindrical, with an elongated neck, equipped with an internal thread for attaching a high-pressure tube or branch pipe.
• Cylinders are made of steel or aluminium. Steel cylinders are covered with a protective anti-corrosion layer, which is used as zinc. Steel cylinders are stronger than aluminum, but they are less buoyant.
• Cylinders are filled with a gas mixture or compressed filtered air. Modern tanks are equipped with overflow protection.
• They are connected to an air reducer, which reduces pressure from 150 to 6 atmospheres throughout the operation of the scuba gear. With such pressure indicators, the respiratory mixture enters the lung machine.
• The lung machine is the main device in the scuba device, since it is used to supply breathing air, the pressure of which is equal to the water pressure on the diver's chest area.

Types of scuba gear

Those who decide to design a homemade scuba gear should be aware that three types of equipment are used in diving: with open, closed, semi-closed circuits. They are distinguished from each other by the method of breathing used.

open circuit

It is used in inexpensive, light and not having large dimensions equipment. Works exclusively on air supply. When exhaled, the processed composition is released into the environment without mixing with the mixture filling the cylinders. This eliminates oxygen starvation or carbon dioxide poisoning. The system is simple in design and safe to use. But it has a significant drawback: it is not suitable for deep diving due to the high consumption of the respiratory mixture at great depths.

closed circuit

Scuba diving works according to the following principle: the diver exhales air, which is processed - cleaned of carbon dioxide, saturated with oxygen, after which it is again suitable for breathing. System advantages:

• small mass;
• small dimensions of equipment;
• diving in deep water is possible;
• a long stay of a scuba diver under water is provided;
• there is an opportunity for the diver to go unnoticed.

This type of equipment is designed for a high level of training, it is not recommended for beginners to use it. The disadvantages of the system include its significant cost.

Semi-closed scheme

The principle of operation of such a system is a hybrid of open and closed circuits. Part of the processed mixture is enriched with oxygen, after which it is again available for breathing, and its excess is discharged into the environment. At the same time, different immersion depths provide for the use of various gas breathing cocktails for breathing.

Backup source

Many divers use mini scuba as a backup tank. The mini model is a compact system designed for breathing underwater at shallow depths. It includes a reducer with a mouthpiece and a small-capacity air tank. Air volume indicators depend on the individual characteristics of the scuba diver.

The use of scuba gear

Scuba gear helps a person swim freely underwater. It eliminates the need to walk along the bottom all the time or stay in an upright position. This is due to the widest use of equipment not only by divers, but also by cameramen, repairmen, archaeologists, ichthyologists, hydraulic engineers and photographers, etc.

Many are trying to make a homemade scuba gear with their own hands. The motivation for making such a decision can be both a desire to save money and an irresistible love for technical creativity. Netizens willingly share tips and tricks on how to make a device at home.

"Sparka": homemade scuba gear from a gas cylinder

You will need:

• Oxygen cylinders, metal-composite, steel aviation cylinders with cut-off valves for the oxygen line (against kickback) and check valves. Volume of each: 4 l, weight: 4.200, operating pressure: 150 bar.
• Aviation oxygen valve
• Flywheel homemade.
• Reducer from the aircraft ejection seat.
• Soviet gas reducer for propane.
• Homemade spring made of stainless steel wire, etc.

How to make?

1. The cylinders are connected using stainless steel clamps (can be made from washing machine tanks). Inserts made of wood are inserted between the cylinders, covered with epoxy-based fabric, with black PF paint. Holes are drilled in the gearbox cover so that water does not stagnate.
2. The automatic activation of the oxygen system is removed. A lever with a check is installed.
3. A self-made regulator for scuba diving can be made from a stainless steel wire spring connected to the safety valve of the gearbox and a duralumin cover with a fitting to the outlet for connecting a lung machine. The reducer is adjusted (pressure setting - 6.5 bar).
4. A lung machine can be made from a Soviet gas reducer. It is necessary to insert 2 fittings made of a duralumin tube (diameter - 16.5 mm) into its body. Put a mouthpiece with a stainless plate clamp on one of them. In the other, paste a textolite glass with a valve from a gas mask. If one mushroom valve quickly fails, it should be made from a rubber reinforced circle (can be cut from shoe covers of the Soviet chemical kit) and a bolt with a nut that fastens the valve directly to the seat. Instead of the old connecting fitting, a new one is made of duralumin, which is glued on an epoxy basis in place of the old one. Valve seat diameter - 2.5 mm.
5. To counteract the opening force of compressed air, a self-made pulling spring is installed in the lid, which is hooked to the horizontal pin in the upper part of the lid.
6. The membrane is made from the same rubber from shoe covers. A washer with a small weight is installed on it to eliminate vibration during inhalation. The inspiratory valve cushion can be machined with a high-speed emery tool by hand from a piece of rubber.
7. The lung machine is tightened with three bolts. Tightened even by hand, they are able to hold the membrane well. The lower part of the lung governed demand valve is equipped with a riveted stainless steel plate, which is installed under the chin, for additional comfort of using the equipment.
8. Shoulder nylon straps are made from pieces of halyard without adjustment due to lack of need. The waist belt may not have a quick release buckle.

Description of the result

At a depth of 10 m, scuba gear allows you to perform hard physical work (pulling along the bottom of cobblestones or swimming fast) without the effect of lack of air. It is not equipped with a purge button, but it is quite possible to do without it. The lung governed demand valve only needs to be adjusted at the first use, after which the minimum adjustment is made by moving the inspiratory valves. Works at a pressure of 6-7 bar. Inhalation efforts are characterized as quite acceptable, similar to AVM-5. Weight - 300 g. Connects to the hose without gaskets, using a cone connection. The device is very light (about 11.5 kg), compact and streamlined. It does not have a minimum pressure indicator.

Another option for homemade scuba gear from gas cylinders

1. Prepare a balloon. A container with a volume of up to 22 liters is used, depending on preferences. You can use 2 cylinders of 4.7-7 liters. For normal diving, a 200 bar cylinder is suitable, for technical diving - 300 bar.
2. Prepare reducer with pressure similar to cylinder pressure.
3. Connect the reducer to the cylinder. Make sure that the pressure in it is 6-11 bar higher than the ambient pressure.
4. Connect a hose to the reducer, attach a lung machine to the hose. If it works properly and the master does not make mistakes, the pressure corresponds to the pressure of the environment.
5. Attach regulators. Their number depends on the tasks. For the planned recreational diving, 2 regulators are needed: the main and the backup.
6. Install a buoyancy compensator (not necessary for proper functioning of the scuba unit, but makes diving easier and safer).
7. Inflate the cylinder with oxygen and check the assembled system. If all its elements are connected without errors and the device works, you should carry out the first trial dive to a shallow depth. If it was successful, the scuba gear can be considered ready for use.

Homemade fire extinguisher scuba gear

1. A cylinder from a carbon dioxide fire extinguisher is used (pressure - 150 bar, capacity - 5 l, weight - about 7.5 kg)
2. The valve must be turned to a round shape, screwed into a T-shaped fitting (from a cylinder from an ejection seat), which must be equipped with a charging valve.
3. Two dural plates are installed on it, pulled together.
4. They are reinforced with a gearbox, which is a converted second stage of the oxygen reducer from the ejection seat (operates from 8 bar).
5. A self-made safety valve is made, the diameter of the membrane is reduced using 2 plates.
6. A reducer valve seat with a diameter of 1.2 mm is being made, a valve cushion (from fluoroplastic), in addition, some other minor alterations must be made.
7. The lung machine is similar to the model described above (see the Sparka section: homemade scuba from a gas cylinder). A housing from another gearbox is used, as well as homemade exhalation and inhalation valves. The balloon is fixed with duralumin clamps on the fiberglass back.

Result

The device is reliable and trouble-free in operation. The main maintenance problem is the corrosion of the duralumin gearbox housing in salt water. To solve the problem, it is recommended to use silicone grease. The equipment is not equipped with a pressure gauge, there are no filters (you can use a siphon tube in a cylinder with small holes at the end). Weight - 9.5 kg.

On the Internet, there are other options for home-made scuba models from a fire extinguisher.

Option number 1

• The device is made from a cylinder - a receiver (2 l) from a fire extinguisher.
• Attaches to chest area.
• Instead of a regulator, a self-made pneumatic button is used to manually supply air for inspiration.
• The device is equipped with a non-return valve, which cuts off the air line in the event of a rupture of the hose supplying air.
• There is no gearbox, therefore it is used at a limited immersion depth.
• The diaphragm is pressed against the valve seat by a spring. When you press the lever, it rises and the air goes to the breath. Exhalation is made into the water using the exhalation valve.
• Air supply from the surface is carried out from a transport welding cylinder with a volume of up to 40 liters. A lung machine is connected to the device.
• A pneumatic button attached to the hand is more convenient than a button that you have to hold in your hand. The hand is partially released and used to perform some kind of work.

Option number 2

• A fire extinguisher cylinder (1.5 l) is used.
• The device uses a manual inhalation system.
• The equipment is equipped with a valve - a pneumatic button, a valve and a reducer.
• It consists of a tube screwed into the fitting from a fire extinguisher, in which there is a plastic check valve pressed against a conical seat by compressed air and a spring. A body with a membrane and a pin pressing on the plastic valve is screwed onto the tube. On the reverse side is a lever designed to be pressed with a finger.
• The air leaving this device passes through a nozzle (diameter - 2 mm), then goes to the breather into the mouthpiece. Exhalation is carried out using a valve.
• The weight belt is quite simple to manufacture. It is made from lead cylinders cast from a duralumin tube with a longitudinal section. Equipped with a self-made quick-release buckle.

There is no doubt about the reliable functioning of the equipment, but the tightness of the plastic valve that closes the cylinder is problematic

How to make scuba gear from a bottle?

The Internet offers instructions on how to make homemade scuba gear from a bottle. According to the author who provided it, a sprayer used in horticulture can be used for this. The easiest way to find it is in a specialized store for gardeners. When choosing a container, you should not give preference to too large bottles: they will strongly “pull” upwards.

You will need:

• sprayer (pump);
• flexible hose (plastic);
• underwater snorkel used for diving;
• container (bottle).

Technology:

1. First, remove the limiter installed in the sprayer. This is necessary so that as much air as possible comes out of the sprayer.
2. A hose is pulled over the top of the sprayer, carefully sealed with silicone or hot glue.
3. A cap from a plastic bottle is installed on the bottom of the underwater tube, with a pre-drilled hole according to the diameter of the hose.
4. A hose is inserted into the hole, carefully sealed, sealed. A simple scuba gear is ready.

Operating principle

The bottle is connected to a pump sprayer and filled with air. The 330 ml container is filled with air with 50 strokes. This amount of air is sufficient for 4 full breaths. A larger container should be equipped with a load, as an air-filled bottle will float up. To extract air from the bottle, just press the appropriate button on the atomizer.

Conclusion

Self-made scuba will save money and provide an opportunity to experience the incomparable pleasure of participating in the creative process. In order to ensure the safety of their own life and health, craftsmen must strictly follow the instructions.

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Scuba (lat. Aqua, water + English lung, light = Aqua-lung, “Water lung”), or scuba (English SCUBA, Self-contained underwater breathing apparatus, autonomous breathing apparatus under water) - light diving equipment, allowing you to dive to depths of up to three hundred meters and easily move under water.

Components of a scuba gear
Cylinder - one or two metal cylinders with a volume of 7-18 liters (sometimes there are 20 and 22 liter cylinders).
Regulator - there may be several on one scuba gear (depending on the tasks solved during the dive). It usually consists of two parts: a gearbox and a lung machine.
Buoyancy compensator - not required, but commonly used today.

The work of scuba gear is based on the principle of pulsating air supply for breathing (only for inhalation) in an open pattern, i.e. with exhalation into the water. This eliminates the mixing of exhaled air with inhaled air or its reuse, as happens in devices with a closed cycle.
Breathing in scuba gear is carried out according to the following scheme: air compressed in cylinders enters the lungs through a mouthpiece from a breathing machine, and exhalation is made directly into the water. Air in turn from each cylinder goes through the stopcocks into a metal pipe connected to a pressure reducing valve. A reinforced rubber tube with a manometer located on the swimmer's chest is attached to the nozzle. Reaching back and turning the stopcocks, the swimmer
can determine by the pressure gauge how much air he has left. A pressure gauge is to a swimmer what a gas gauge is to a car driver: it allows the swimmer to judge how long they can stay underwater.
The main part of the scuba design is a breathing (lung) machine, with the help of which air is supplied to the respiratory organs of a person in the required amount and under pressure corresponding to the pressure of the surrounding water. A special valve closes the exhalation tube during inhalation, and the inhalation tube during exhalation. This prevents the loss of fresh air and the inhalation of used air. The first models of scuba did not have an exhalation tube until Cousteau discovered that the apparatus, which worked perfectly when the swimmer was face down, failed if he rolled onto his back. This is because the air pressure in the breathing valve and in the outlet near the swimmer's mouth were not the same. The way out was found in the fact that by means of an exhalation tube the outlet was moved to the back of the swimmer's head.
According to their design, breathing machines are single-stage and two-stage, without separation of air reduction stages and with separation. At present, two-stage automatic machines with separated reduction stages are mainly used. The scheme of their action is as follows:
Reducer 1 is mounted directly on the cylinder with compressed air. From it, air through a flexible smooth hose 2 enters the breathing machine 6, which is located near the swimmer's mouth. The respiratory automaton is divided by membrane 5 into internal (submembrane) and external (supramembrane) cavities. In the body of the machine there is a swinging inhalation valve 4 with a stem located at an angle to the membrane. When inhaling, a vacuum is created in the internal cavity of the machine. Under the action of external pressure, the membrane, bending into the internal cavity, then presses on the inhalation valve stem and warps this valve 4 relative to the seat. Through the resulting gap, air enters the internal cavity of the machine.
After the end of inspiration, the pressure in the internal cavity equalizes with the external water pressure, the membrane returns to its neutral position and stops pressing on the valve stem. Then, under the influence of the force of spring 3, the valve sits on the seat and stops air from entering the internal cavity of the machine. Exhalation is carried out through the exhalation valves located in the body of the breathing machine.

Many novice divers who decide to purchase their own equipment are wondering how to choose scuba gear. Today, specialized shops offer a wide range of diving equipment, designed for both beginner divers and experienced divers. To decide which equipment to buy, you should understand what is the difference between them.

What is scuba gear made of?

Scuba gear consists of the following components:

• balloon. Usually one or two containers filled with breathing mixture are used. One container holds from 7 to 18 liters of compressed air;
• regulator. As a rule, it consists of two parts - a reducer and a lung machine. One scuba gear can contain from one to several gearboxes;
• buoyancy compressor. This is a special inflatable vest, thanks to which the diver can regulate the depth of the dive.

Types of scuba gear

Three types of scuba gear are used, differing in the principle of breathing.

open circuit

Quite inexpensive, light and not having large dimensions equipment. This type of breathing works only on the supply of breathing mixture. The recycled air is exhaled into the environment and does not mix with the air in the cylinders. This avoids oxygen starvation or carbon dioxide poisoning. It is simple in design and safe to use. However, there is one significant drawback: models with an open breathing pattern are not intended due to the high flow rate of the breathing mixture at depth.

closed circuit

The principle of operation of this type of scuba gear is that the recycled air exhaled by the diver is cleaned of carbon dioxide, saturated with oxygen and again becomes breathable. Such a system has many advantages:

• small weight and dimensions of equipment;
• the possibility of diving in deep water;
• long duration;
• opportunity to go unnoticed.

However, this type of equipment is designed for a high level of training and is not suitable for beginners. The disadvantages include a significant cost.

Semi-closed scheme

The principle of operation of such a system is a hybrid of open and closed breathing patterns. That is, part of the recycled air is again enriched with oxygen and becomes available for breathing, and the excess is released into the environment. At the same time, different gas cocktails for breathing are used for different depths of immersion.

Backup source of breath

Many divers prefer to use mini scuba as a backup tank. Mini models are a compact system designed for breathing underwater at shallow depths. The mini-scuba system includes a small-capacity air tank and a reducer with a mouthpiece. The volume of air depends

Cylinder selection

When choosing diving cylinders, it is necessary to pay attention to their certain characteristics.

Material

As a rule, containers for respiratory mixtures are made of steel or aluminum. Steel has increased strength, but is prone to corrosion, which cannot be said about aluminum. However, most people prefer to purchase steel cylinders, since, with proper operation, they can last more than one year.

Quantity and volume

How many bottles to buy is a matter of personal preference. It makes no difference what to use: one bottle with a volume of 14 liters or two bottles of 7 liters. The volume should be increased if a dive is planned that requires a large supply of breathing gas.

Many professional divers choose not to purchase cylinders and instead purchase their own compressor. Having your own compressor, you can simply rent cylinders and fill them yourself. Buying a new or used compressor is a matter of personal preference and financial capabilities, since the compressor is quite expensive. For beginners, it is recommended to purchase your own compressor only if you plan to dive seriously and for a long time.

For beginners who do not know how to choose scuba gear, it is recommended to contact specialized stores, where consultants will give all the necessary professional recommendations. Saving on equipment is not worth it, since high-quality conjugation will regularly last for more than one year.