Archive for December, 2005
For the smaller beginners, a first time water skiing experience is the most special. If their first time is a bad one, then chances are they will probably never want to try it again. That is why it is so important that you choose a teaching facility that emphasizes safety and has a nurturing environment and understands the special needs of children.
With children, there is usually a second instructor in the water along side the student to provide safety, guidance and some emotional support as well.
You will find that places that teach beginners how to water ski, have the highest quality of equipment and provides the proper water gear especially designed to help the student to enjoy a safe and fun ride. Remember safety should always come first.
If you are having someone you know show you the ropes to water skiing, then remember to start out on a private body of water. You want to make sure that you are not near boats and other people. You want to start off without any distractions.
From young, scared children to nervous adults, water skiing instructors are usually committed to making your first time water experience a memorable and fun one.
The basic scuba equipment is the breathing apparatus and the face mask. However, for safety and comfort in the water, you should consider providing yourself with some of the scuba accessories described here, depending on the type of diving you are planning to do.
Life jacket
Some type of notation gear is required for use with the scuba. The standard type is a life jacket an inflatable life preserver-which is a vest-type jacket inflated by a carbon-dioxide cylinder. A tube is also provided for inflation by mouth if the gas cylinder should fail. When inflated, the preserver holds the head well clear of the water. This life jacket should be worn under all gear that can be jettisoned. When donning your gear, put the jacket on over your protective clothing, but under the releasable gear such as the scuba and the weight belt.
Belt and knife
It is a general precaution in scuba diving to carry a knife sheathed in a scabbard on a suitable belt. The knife is your safeguard against entanglement. Secure the knife to the belt with a lanyard to prevent loss. Two satisfactory types of knives are the standard diver’s knife and the Army standard combat sheath knife, which are generally available in Army-Navy surplus stores or at sporting-goods shops.
Swim fins
Flexible fins for the feet are an important accessory. Without swim fins, you will find it extremely difficult to propel yourself adequately with scuba. The fins are particularly valuable for swimming to the surface in an emergency ascent. Even when diving with negative buoyancy, you should use your fins. The fins increase the propulsive force transmitted from the legs to the water. For maximum efficiency they should have a large blade and considerable rigidity. Try a few different types to determine which works best for you. If the blade is too large, or if the fin is too rigid, there is excessive back pressure on the fin, which quickly produces fatigue. On the other hand, if the blade is too small or if the fin is too flexible, there is insufficient thrust again producing fatigue. Comfort is an important factor in the use of fins. Tight or loose fins can chafe or blister your feet. Be sure your fins fit well, and use a larger size over a suit or protective covering for the feet.
Depth gauge
Depth gauges are designed to be worn on the wrist or attached to some part of the equipment. The United States Navy has conducted tests on various types of depth gauges and warns against placing full reliance on them. However, they do give a fairly good estimate of the depth below the surface.
The two general types of depth gauges are the open manometer type and the Bourdon tube dial gauge. The open manometer gauge is a flat plastic piece that incorporates a graduated tube. One end of the tube is open, the other closed. On descent, sea water enters the open end of the tube, compressing the air trapped inside. Depth is then read by the height of the water level inside the tube. Poor visibility of the gradations, variations caused by temperature changes, unevenness of the tube bore, crowded gradations, and loss of entrapped air, affect the reliability of this gauge, and its use at depths below 33 feet is not recommended.
The Bourdon tube gauge consists of a spiral-shaped metallic tube with one end open and the other closed. The tube is mounted in a sealed circular case, so that the open end is exposed to sea water. The closed end of the tube is connected by a linkage to a pointer on a calibrated dial. On descent, water enters the open end of the tube and pressurizes the bore. The differential between the bore and the sealed case causes the tube to deflect from its original shape. This movement is transmitted to the pointer by the connecting linkage, and the depth is read on the graduated dial. On ascent, the elasticity of the tube causes it to resume its original shape. This type of gauge is somewhat more reliable than the open manometer type, and if it is protected against possible damage by impact or shock, it should give readings that are accurate within 1 and 3 per cent of the operating depth. It operates satisfactorily down to depths of about 50 feet.
It does not matter if you are child or an adult, beginning water skiing is a fun and exciting adventure. When you are a beginner water skier, it is important that you learn the basics first before you attempt any tricks or jumps.
There are certain places that are committed to making your first time at water skiing a great and memorable experience. Most of the places that teach beginners are located at a lake or somewhere you will be relaxed.
The best thing to do is start on land and learns the fundamentals of body position, techniques and the safety involved in water skiing. Once the instructor and the student are confident in understanding the basics on land, you can then move on into the water.
Some places where you go to learn water skiing have a static boom on the side of the boat to offer stability for the beginning water skier. This will allow the person teaching the sport to be close and watch intensively.
The compressed air in your scuba tanks must be free from carbon monoxide, carbon dioxide, oil, vapor and other impurities. Generally, the industrial-type of compressed air may not be safe for scuba use. However, companies which supply compressed oxygen for medical use usually have facilities for providing compressed air. In many localities the local fire department is willing to provide a supply of compressed air from the charging station for the compressed-air breathing apparatus used in the department. Many sports-equipment stores have equipment for charging scuba tanks. Also, there are on the market several makes of lightweight, portable air compressors, especially designed for charging scuba tanks.
Maintaining Your Scuba
All of the scuba equipment on the market is well constructed, but your equipment can be damaged if it is not given reasonable care. If you keep the cylinders, regulators, hoses, tubes and mask assemblies clean, you can expect trouble-free operation for a long time. However, if you encounter any problems that call for replacement of parts or major repairs, it is better to send the apparatus to the dealer or directly to the factory rather than to try to fix it yourself.
The following rules may help you keep your scuba in proper operating condition:
Always stow a cylinder-mounted regulator separately from the cylinders. Never leave the regulator attached in storage.
After use in sea water, thoroughly rinse the regulator and associated assemblies in warm, fresh water. Hang the regulator by its yoke to dry.
Do not allow any water to enter the high-pressure air inlet of a regulator. Insert a rubber stopper into the yoke immediately after detaching a cylinder-mounted regulator. Keep it in place when rinsing. Remove it only before mounting the regulator.
When washing the regulator, pour fresh water into the mouthpiece several times. Make sure that both the inhalation and exhalation sections of the regulator and breathing tubes are well rinsed.
Make an occasional inspection of rubber exhaust valves to see that salt deposits do not lodge around the edges and cause leakage.
Rinse the air cylinders and high-pressure manifold thoroughly in fresh water to remove all traces of salt deposit. Stow the cylinder assemblies carefully when not in use.Compressed air stored for long periods of time does not show signs of contamination; however, it is recommended that the air be changed at least once a year in idle tanks. Stow cylinders fully charged. Provide yourself with a pressure gauge and check the pressure occasionally. Keep any tanks holding less than 1,500 pounds per square inch away from places where they may inadvertently be put into use.
The arrangement of the component parts varies considerably among the different makes of scuba. If you are going to use an unfamiliar scuba, the instruction manual should be studied, and if at all possible, some instruction should first be taken from a person who is qualified in the use of that particular scuba.
The united states divers’ corporation aqualung: In this scuba, the first-stage regulator, demand valve regulator, and exhaust valve, form an integral unit mounted on the high-pressure manifold attached to the cylinders. The cylinders are worn on the back and are fastened to the diver by means of a harness assembly. They are worn with the manifold up, so that the demand regulator rides the back of the neck. A corrugated breathing tube supplies air from the demand regulator to the mouthpiece. Another corrugated tube carries the exhaled gases from the mouthpiece to the exhaust valve, which discharges the gases to the water. The position of the exhaust valve close to the demand regulator diaphragm minimizes the difference in pressure (water pressure) between the two, so that inhalation and exhalation occur at nearly identical water pressure. The air-reserve mechanism is integral with the manifold and is located above one of the cylinders. It is manually operated by means of a pull rod.
The scott aviation corporation hydro-par: This apparatus uses a completely different arrangement of components from the aqualung. The cylinders are secured to a back plate which has a shoulder harness for attachment. The cylinders may be worn with the cylinder stop valves up or down. The first-stage regulator is integral with the high-pressure manifold mounted on the cylinders, and reduces cylinder pressure to about 100 pounds per square inch over bottom pressure. A medium-pressure hose supplies this low-pressure air to the demand regulator. The demand regulator is mounted directly into a molded housing on the right side of the mask, which replaces the mouthpiece. The exhaust valve is mounted similarly into the left side of the mask. A special-pressure balancing mechanism subjects the exhaust valve to demand regulator pressure and compensates for pressure differences between the two locations. The air-reserve mechanism on the Hydro-Pak is located in the first-stage regulator and is operated by a knurled knob mounted on top of the first-stage regulator.
The Hydro-Pak contains an added feature not found in the aqualung or air lung. It has a water-ejection button which is used to clear the mask if it should become flooded. This button is located on the demand regulator. Pushing the button depresses the diaphragm, causing a free flow of air to enter the mask and force out the water. Hook a finger under the mask to let the water out in this process, because the pressure-balancing mechanism locks the exhaust valve shut during this operation. The water-ejection button is useful for clearing large amounts of water, or at any time that a free flow of air is desirable. You can clear small amounts of water by tilting the head to the left and draining water through the exhaust valve by exhaling.
The northill company air lung: This equipment uses the same arrangement of components as the aqualung, with some differences. It has no intermediate-pressure stage because the demand regulator is especially designed to work directly from cylinder pressure. Furthermore, the exhaust valve is integral with the demand regulator diaphragm, and exhaust occurs through the diaphragm from a chamber which is isolated from the demand valve itself. This subjects the demand regulator and the exhaust valve to exactly the same hydrostatic (water) pressure. The location of the air reserve mechanism on the airlung is also different. The mechanism is an integral part of the demand regulator and is manually operated by means of a lanyard attached to a lever.
Breathing Tubes
The breathing tubes currently used in scuba consist of nonkinking, corrugated, or bellows-type rubber or neoprene hose. There are usually an inhalation tube and an exhalation tube. The inhalation tube carries air from the demand regulator to the mouthpiece or mask, and the exhalation tube carries the expired gas to the exhaust valve where it is discharged into the water.
Check Valves
Your scuba may use 3 types of check valves: inhalation, exhalation, and exhaust. The breathing check valves may be incorporated into the full face mask or the mouthpiece, and a check valve is always a part of the exhaust-valve assembly.
The inhalation check valve prevents exhaled air from
After a course of lectures and practice, the instructor and pupil dive in a check-out swim.
entering the inhalation tube. Even more important, it prevents water from entering the demand regulator when the mask or mouthpiece floods.
The exhalation check valve prevents water in the exhalation tube from flooding the mouthpiece. Neither of these valves is essential for scuba use, and either or both may be missing from your outfit. However, they do greatly simplify the problem of clearing water from the system.
The important exhaust check valve prevents water from entering the system. All open-circuit scuba must have at least one check valve-the exhaust valve.
The Mask and Mouthpiece
Your scuba may include a full face mask, a mouthpiece, or a combination of the two to provide you with air. A full face mask usually has the demand regulator mounted directly on the mask. Mouthpieces and mouthpiece-mask combinations are commonly used with breathing tubes and cylinder-mounted demand regulators.
