The deeper the diver goes, the higher the pressure is.
The collective noun is a bubble of scuba divers.
scuba divers
Many people use a SCUBA suit for diving. Sport divers, police divers and some Navy recovery divers.
Free divers do but scuba divers do not need to. Scuba divers take their air with them and would have no need to hyperventilate.
seebees
They swim
Scuba divers require increased air pressures in their air tanks while diving because the pressure on their bodies increases.
In the Water....
Scuba - self contained underwater breathing apparatus
Scuba Bob's Ocean Quest - 2006 Fearless Divers Scuba Rangers 2-7 was released on: USA: 2007
Scuba regulators, also called 'diving regulators', are vital for scuba divers to properly obtain oxygen from a tank. Regulators are available for purchase through diving specialty stores such as Prime Scuba, House of Scuba, and Divers Direct.
Skin divers are people who dive into the ocean without using special equipment, unlike Scuba divers.