Diving gases which are used (in order of frequency in everyday use):
Many people use a SCUBA suit for diving. Sport divers, police divers and some Navy recovery divers.
Scuba - self contained underwater breathing apparatus
water proof ones
scuba divers use pressure meter because the deeper down you go the more pressure builds upAdditiona depth gauge or a dive computer
Scuba Divers use a Sonar to find treasure or a hidden ship.
For oxygen masks for firefighters, scuba divers etc
This is a dive using scuba equipment you are used to seeing. It is where you breath from a scuba cylinder and exhale all the gas you breathed as bubbles. Since you are not recycling or rebreathing any of the gas, the circuit is open. Closed circuit or semi-closed circuit is where divers use "rebreathers" and rebreath the majority of their gas. 100% of the gas can never be rebreathed, so a very small amount is exhaled as bubbles.
In recreational diving, most divers use compressed air (as in the normal air we breather at the surface). Some divers are also trained to use special gas mixes called Nitrox which have a higher oxygen content and lower Nitrogen. Professional (or commerical) divers tend to use more advance mixes such as Heliox or Trimix which combine Oxygen, Nitrogen and Helium.
Divers use substances with high density (ie. lead) to help them sink, and substances with low density (ie. air) to help them float. That way they control their bouyancy.
He was he inventor of the SCUBA (Self-Contained Underwater Breathing Apparatus) equipment divers use to explore under the sea.
Sky divers use parachutes to jump from planes. SCUBA divers have difficulty searching Loch Ness because there are many inlets and lagoons, and many have so much sediment that the water is very cloudy.
They don't breathe normally on their own.They have to use pressure regulators to breathe naturally, overcoming the extreme pressure deep underwater.A snorkel and oxygen tank help the divers breathe when they are underwater.