Snorkel tube usually 30 cm long (wet tube), its inner diameter of about 1.5 to 2.5 cm wide, generally L or J-shaped, in the lower part of the mouth, usually made of rubber or plastic. Through it snorkel's mouth and nose can sink in the water, but continue to breathe. The snorkel usually has a piece of rubber attached to the snorkel strap. Old style snorkels are also directly sandwiched between the strap and the head, but this often leads to leaks in the goggles.
The most common breathing tube is a simple tube that can be completely submerged. Snorkeling There are two ways to drain: You can blow a gas after it has been exposed, or you can vent it as soon as it reaches the surface of the water, then expose the water, then square your head and breathe in. The latter is through the exhaust pipe water squeezed out, this method is more effective, but requires some training. Snorkelers have a sink on the mouth of some modern snorkels underwater so that a small amount of water can stay in the snorkel without affecting breathing. Some have a one-way valve in the water pocket, water can be automatically drained after filling water. Some snorkels have a valve on the top to prevent water from entering the snorkel when snorkeling underwater. Some of the more advanced breathing tubes even prevent water from splashing into the water, preventing water from entering the snorkel's mouth.
The development of breathing tube technology makes it possible to solve this problem now. For example, advanced breathing tubes use one-way valves to separate inhaled and exhaled tubes, and submerged tubing is sealed so that snorkelers do not have to exhale first after rising . Currently, snorkels are generally divided into dry and wet tubes (wet tubes including semi-dry tubes): Dry tubes ensure that no water will fill the tube while the tube is being diverted, while the wet tube is filled with one full tube of water. After the snorkeling float to float to the surface after the water, the wet pipe needs full drums to blow the water out of the pipe and drain valve, and then breathe in.