Scuba divers use a snorkel as a safety device in case they have to float for extended periods of time while locating a boat or being located by a boat. The snorkel is also used to swim on the surface, and to and from dive sites without using up precious gas from the cylinder.
Parts of a Snorkel
A snorkel consists of the tube that varies in length, bore diameter, and shape. The inside bore diameter of the snorkel tube is important. A large-bore tube with an inner diameter of about 2.5 centimeters/1 inch is easiest to breathe through. There is a huge range of designs to choose from, and it is a good idea to test them first in water before you decide which one is for you.