Because pressure increases the further down you go. A unpressurized tank would collapse under this weight. Actually, the pressure in the tank is not to prevent it from crushing, but to allow it the diver to breathe. The greater the pressure in the tank, the greater the amount of breathing air you have available. As ambient pressure increases (ie by descending), your lungs require more air to fill them, as you are then breathing compressed air into your lungs. If you tried to breathe atmospheric pressure at depth, you could not fill your lungs. The deeper you go, the harder it is to breathe... Try breathing through a 6ft snorkel to the surface, and see how difficult it is to inhale. Therefore, the tank is pressurised, 1/ to allow you to breathe effortlessly at depth, 2/ to give you more time at depth, and 3/ to keep water out of the tank.
A cardinal rule for scuba diving tanks is to never completely empty your scuba diving tank. When planning your scuba dives, it is important that you consider to complete your dive with enough air left within your scuba diving tank.
You can buy scuba tanks at the internet page "DiversDirect" or in a special diver store. Or you buy on Ebay a used scuba tank, its cheaper but the scuba tank could be defect or something else.
It is stored in pressurized tanks.
SCUBA tanks are metal (usually steel or aluminum) that are filled with compressed air. This is loosely related to a pneumatic system.
Scuba tanks need to be visually inspected and need a hydrostatic test done every five years.
Used scuba tanks can be found on eBay, but for new equipment, there are brick and mortar "dive shops" that sell tanks and other diving accoutrements. Scuba tanks can be found online at Amazon, and at other online portals that specialize in diving equipment such as LeisurePro.
Mask, fins, snorkel, SCUBA tanks, Buoyancy Control Device and weights. It's also nice to have a wetsuit and dive computer.Also, see the answer in the question "What is the required equipment for scuba diving?"
Hide behind those water tanks. The scuba tanks are filled and ready to go.
They are made usually from Aluminium or steel
Scuba divers also wear lead weights on a belt
Most SCUBA divers dive with compressed air, which is normal atmospheric air compressed into a scuba tank.
they have weight belts
it doesn't affect the tank
By oxygen tanks - similar to SCUBA divers.
so the diver can breath.
Tanks are usually filled from compressors, which simply pump in new gas until they reached the required pressure. Most dive shops have one or more compressors for this purpose. Sometimes tanks are directly filled from other tanks (called 'banks'), but that is usually when you need to fill them at a location where you don't have a compressor.
Scuba Cylinders must be tested VISUALLY (called a visual test !!) every 2.5 years. They must have a HYDRAULIC test every 5 years (previously 4) (hydraulic is also known as hydrostatic testing)
A Normal scuba tank can usually fill around 50-75 3000 psi tanks. This is assuming though that the compressor is working. That and the tanks are at room temperature.
How It's Made - 2001 Car Tires Silk Art Conservation Scuba Tanks was released on: USA: 1 August 2013
Propane and LNG, liquid natural gas are two of the most common. Hydrogen and oxygen used by NASA is also stored as pressurized liquid.
If you mean Scuba tanks, call a dive shop, if you mean emergency breathing tanks, call your local Fire Co.
air, nitrogen, oxygen, trace gases, and sometimes helium
it has scuba tanks of oxigen.