Why does a scuba diver need increased gas pressure in the air tank?
There are two primary reasons why scuba divers require increased air pressure in their scuba tanks. 1. To provide sufficient air to last for the scuba dive. An average sized scuba tank has approximately 12 litres capacity. 12 litres of air would not last a scuba diver very long underwater. Increasing the pressure of the air pumped into the tank, in effect ‘squeezes’ more air into the same volume of tank. A 12 litre tank, pumped to 200x atmospheric pressure, would now contain 2400 litres of breathable air. 2. To provide air at sufficient pressure to match the increased water pressure acting on a diver. As the scuba diver descends in the water, they are subject to drammatically increasing pressure exerted by the weight of water above them (1x atmospheric pressure added for every 10m descended). The air provided by the scuba diver’s regulator (breathing apparatus) will supply air at a pressure which matches the external (ambient) water pressure surrounding the diver. This prevents the div
