Some knowledge about diving

In recent years, domestic divers have grown at a geometric speed, watching friends around them describe the blue ocean in succession. More and more young people are curious about the other 70% of the earth and choose to squeeze out their holidays to take the diver's license. For those of you who yearn for the ocean, you should not only prepare money and time, but also know a lot! Let me show you something about diving. Welcome to read and study.

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Introduction to diving license examination

Diving is a very interesting sport, but considering their physical condition, some people are not suitable for diving:

1. People who have had middle ear surgery or corneal surgery.

2. Patients with chronic emphysema or severe asthma (pneumothorax patients)

3. People with a history of epilepsy or spasm.

4. People with coronary artery disease (such as angina pectoris) or a history of myocardial infarction.

5. Long-term alcoholics.

6. People who can't swim (learning to swim is highly recommended)

After confirming your physical condition, you need to get the opening conditions of this sport.

For experiential diving projects in many places, called DSD for short, you need to be led by a coach (in fact, in many places, the coach takes you), and only dive to 10M~ 12M. OW and AOW certificates are stepping stones to the real diving process. Most people will choose Southeast Asia as the examination place, because the cost is reasonable, the distance is close and the water temperature is comfortable. Leisure divers are divided into two grades.

Open water diver (open water junior diver)

Ow can be played in the underwater depth of 18 meters. The examination contents include still water diving skills, open water diving and cultural theory examination. The exam is very firm. You need to learn all kinds of skills from the coach during the day, and you need to watch videos and books at night to learn knowledge. These four to five days are basically full.

AOW-senior open water diver (senior diver)

Aow can play at a depth of 30 meters underwater, which is the maximum depth of leisure diving. Don't dislike that it is not deep enough. Most of the richest creatures are within 30 meters. In fact, the content of Aow is not much, that is, five dives in open waters and some underwater specialties, which is expected to take 2~3 days. In the final analysis, the main consideration is the adaptability to diving after OW, which is a little more operational, but much more interesting than OW.

Tip: For these two levels, many people choose to take the exam together, and the overall time can be about 6-8 days, mainly depending on the weather and personal situation during the exam. If you find yourself unwell or unable to overcome your fear of water during the exam, please carefully consider whether to take the exam together. From a safety point of view, I suggest you don't worry, there is plenty of time. The two certificates can be tested separately.

All international diving organizations must be approved by China Diving Association before they can enter China to carry out diving training activities. At present, there are five international diving organizations, namely CMAS, PADI, NAUI, ADS and SSI. So far, the diving organization chosen by most divers is PADI.

How to choose diving equipment?

Diving equipment is mainly divided into two categories, light equipment and heavy equipment.

Light equipment: face mirror, breathing tube, frog shoes, diving suit (including jellyfish suit and sun protection suit), diving gloves, diving socks/boots, etc.

Light equipment (some of which need to be prepared when learning to dive)

goggles

There is still a big difference between diving goggles and swimming goggles. They can not only protect the eyes, but also cover the nose. Swimming glasses can't dive. The lenses of diving goggles are very special. Myopic friends try to choose myopic glasses. Almost all coaches will tell you that wearing contact lenses while diving may hurt your eyes. There are many reasons, such as water pressure and harmful microorganisms in seawater environment. The surrounding skirts are generally made of silicone, which is more durable, less likely to cause skin allergies, and more soft and comfortable.

You'd better try the diving shop yourself. When testing, put the mirror gently on your face (without wearing a mask belt) and inhale to see if it fits your face completely. It is important to determine whether you can pinch your nose (this is very important).

Professional diving brands such as V. dive \ ScubaPro \Mares\TUSA are recommended for the face mirror, which can be equipped with a face mirror belt to avoid pinching hair when wearing it.

When using the mirror for the first time, it is necessary to remove the coating. Gently use toothpaste for 20 minutes, and then clean it. Rinse with clean water after each use to prevent seawater corrosion, and remember not to expose to the sun.

You need to defog the front mirror every time you go into the water. The coach will teach you. You can use defogging spray, toothpaste and saliva. . . . Please develop other methods yourself. . . .

breathing tube

Many divers skip the prop of breathing tube directly. In fact, this prop is necessary. Breathing tubes are very useful when you are floating on the water. Many experienced divers will float on the water to see the underwater terrain before diving in new places, which is convenient for making diving plans. You can snorkel for a while at noon. Breathing tubes can be divided into three types: full dry breathing tubes, semi-dry breathing tubes and wet breathing tubes.

Full-dry breathing tube: the air inlet is designed with a float valve, which is the exclusive part of dry breathing tube. However, when the air inlet of breathing tube is lower than the water surface, the float valve will close the air inlet to prevent seawater from flooding into the tube.

Semi-dry breathing tube: there is no floating valve, and the other is the same as the full dry type, which can prevent broken waves from entering the tube, but if it is completely submerged, it will also enter the water. Wet breathing tube: without any valve, it is straight-through and cheap.

fin

From the appearance, it can be divided into paddle fin and split fin. S7q * can be divided into open heel and full foot pocket according to the adjustment mode.

The choice of flippers depends on body shape, diving environment, physical strength and kicking style. Still suggest to try. Everyone's experience of trying flippers is very different. Remarks: Generally, the novice does not recommend jetfin.

diving suit

There are two kinds of clothes commonly used for diving, namely jellyfish clothes, wet clothes and, of course, dry clothes, but that is limited to cold diving environment.

Jellyfish suit:

In many warm waters of Southeast Asia, you can wear jellyfish underwear. It is recommended not to swim naked in the water even if it is hot. Many aquatic organisms can cause skin stab wounds and allergies. Jellyfish clothing has many functions, such as avoiding sunburn, protecting the body and avoiding being stung by marine life.

Wet clothes:

Leisure diving usually wears wet clothes with a thickness of 2 mm to 7 mm, which is difficult to wear, but don't choose too large a size to keep warm. There are many beautiful brands to choose from. You can search on Taobao. In addition to regular brands, there are many expensive brands, which can also be customized according to your preferences. Recommended hooded vest, practical and beautiful.

Dry clothes:

Most of the materials are foamed rubber, which can't completely isolate the body's moisture, but the water in the winter clothes flows slowly, which can prolong the body's heat preservation time. I don't need to explain it here, because it is not used for leisure diving in general, and dry clothes are expensive.

Tip: Depending on the water temperature in the diving area, you need to choose wet clothes with different thicknesses, such as 1mm or1.5 mm at about 30 degrees; Choose 3 mm at 24~28 degrees, and 5mm or 7mm below 24 degrees. Of course, it will be slightly different according to everyone's cold resistance. Diving in Southeast Asia, in most cases, 1.5mm or even the thickness of jellyfish coat is enough.

In addition, I would like to introduce another piece of clothing that I think is necessary-sun protection clothing (skin clothing):

Generally speaking, the sunshine is very strong where people go diving for a holiday. If you don't wear jellyfish clothes, you can protect your body from sunburn through sunscreen clothes. Sunscreen clothing is also called leather clothing. You can buy various outdoor brands of leather clothes to wear on the boat, and pay attention to the sun protection index when buying.

Diving gloves:

It has the function of keeping warm and protecting. However, in many diving areas, in order to protect the environment (to avoid harming underwater creatures), divers are not allowed to bring diving gloves into the sea (please pay attention to this).

Diving socks &; Diving boots:

Individuals are used to wearing diving boots, but they can only use adjustable fins, because sometimes diving on the shore requires walking on long rocks, and boots can effectively avoid scratches. In some places, boots are not allowed to be worn to protect coral reefs, but diving socks are allowed. Rubber-covered flippers can be worn in diving socks or barefoot.

Submersible computer

Diving computer is also called diving computer, but it doesn't mean you can't watch diving computer. Diving computer is an advanced product, which provides you with effective information and attention in various diving situations, but not all diving computers on the market can be called diving computers. Therefore, to buy a diving computer for diving, it is best to choose a brand that specializes in diving computers. When buying, remember to change the settings in the battery calibration table, and don't just buy it cheaply.

Flashlight:

In fact, it is suggested that diving partners prepare a flashlight, which can be used as lighting when diving at night, and can also be used to find small creatures in rocks during the day. This is very interesting. However, not every flashlight is suitable for underwater photography, so the purpose of flashlight should be considered comprehensively when choosing.

Underwater photography:

In fact, underwater photography is not recommended for beginners to try, because in addition to high requirements for photography technology, diving technology is also very high. Underwater shooting can write a big paper, so I won't explain it here. Water shooting equipment also ranges from thousands to hundreds of thousands. To make good-looking works, it is suggested to improve your diving ability. TG4 and RX 100 are recommended for entry-level machines, and lamps are also an important part. The usage of flash lamp and fill light lamp is also very different, and the price of lamp is also outrageous. Step by step is recommended. Enter the underwater photography world from macro.

What a useful prop:

You can tell from the title that these props are really useful. Prop 1: elephant pull. I really tirelessly recommend this artifact to my friends, because when you get out of the water, playing elephant pull can let the ship see your exit position and avoid being injured by the propeller. Playing elephant pulling is a very good habit of safe diving. I suggest you have someone. As for how to use it and what size to buy, do it yourself. Prop 2: Ding-Ding stick is a small metal stick, about the size of chopsticks. It can be used to knock on gas cylinders in an emergency, and it can also be used to play with uncertain underwater environment. Prop 3: Lingling, a small tin can, will have a crisp sound when it is shaken to inform friends around. Prop 4: Flow hooks are very useful in high-flow areas. Fixing yourself on the reef with a current hook can avoid being blown away by the current, and it won't take too much effort because of the top current. Other props, it is recommended to take a good look at the post, here is a brief introduction, there are too many varieties and usage, not to explain them one by one. . . . . .

The easiest way is treasure hunting?

Heavy equipment (many people choose to rent it in diving shops)

Breathing regulator, buoyancy controller (BCD) or flyback, gas cylinder, counterweight, etc!

Although diving shops (or resorts) generally have diving equipment for rent, for various reasons such as 1. Health problems, 2. Whether it is suitable or not, 3. Usage habits, 4. Underwater comfort and safety.

If economic conditions permit, buying personal light equipment will make diving safer and more interesting. As a rookie preparing for textual research, I personally suggest that you can prepare some light equipment, and then consider these professional-grade equipment after getting the diving certificate.

Come, finally briefly introduce the common diving equipment brands on the market:

Scubapro:

American brand. This brand is not the most professional, but it is the best seller in the world. It is also a special diving brand for the US Navy. This brand has designated OEMs all over the world, making different products for different ethnic groups in different regions, which is why we Asians with flat noses still find Scubapro's face mirror very comfortable.

Scuba:

The inventor of scuba can be said to be the top and most professional scuba system brand. It has eight sub-brands, and each sub-brand has its own professional product classification. For example, Sea Quest specializes in BC buoyancy vests, and Deep See specializes in face mirrors and breathing tubes.

Poseidon:

Sweden's famous brands, besides Electrolux, IKEA and Ericsson, Poseidon is also famous for diving. The origin of this brand name is easy to understand: Poseidon? Poseidon. Poseidon's products are also diving equipment brands designated by the Royal Navy. 、P8 B& amp； W. w- R9 C9 J，n

Tusa:

Japanese brands. The advantage is not only beautiful, but also beautiful. Have you ever seen a pure white diving suit? Have you ever seen pink and blue frog shoes? Such bright colors can only be found in Tusa's catalogue.

Mare:

Italian brand. Italy is a country that has no shortage of famous brands in any field. The mare brand is basically as famous as Ferrari in diving. From the brand point of view, mares is not committed to high-end products, but to mid-range products, so its practicality is extremely prominent.

That's all. As an introduction, you should have a preliminary understanding. I hope these are helpful to everyone. Diving is a very dangerous but interesting activity. Believe me, the other 70% of the world on earth is amazing. As long as you can strictly remember the coach's teaching, be ashamed to go to school, and be responsible for your own life and your buddy's life, every diving will be a wonderful experience.