There are a number of different gases for diving.
Most commonly, air is used for recreational diving. Sometimes, nitrox is used which is a higher proportion of oxygen. This is usually 30-35% oxygen instead of the ~20% in air. This has the benefit of less nitrogen so less "on-gassing". This increases the bottom time and reduces the decompression stops.
For commercial diving, there are a number of other gases used such as Trimix which I believe has Helium in it.
seriously? it is not diving and you don't scuba to breath in air.
Most SCUBA divers dive with compressed air, which is normal atmospheric air compressed into a scuba tank.
Different scuba gear types weigh different amounts. The oxygen tank is the heavy part of the scuba diving gear.
A scuba diver can purchase many things for scuba diving at the Air Hog online shop. They can purchase dive knives, dive lights, dive computers, and dive bags which will help them in scuba diving.
Scuba divers require increased air pressures in their air tanks while diving because the pressure on their bodies increases.
You can use a scuba tank, but that is it.
Compressed air used for SCUBA should smell like regular air. There may be a slight rubber smell from the regulator. When in doubt, it is safer to get your tank refilled than to dive on contaminated air.
scuba
The vest is simply called a scuba vest. It's to hold your air tank and regulators :)
Scuba Breathing Apparatus.
one percent
from holding their breath and ascending.