Each mix is bespoke .
Each mix is created using gas blending techniques , which often involve the use of booster pumps to achieve typical diving cylinder pressures of 200 bar ( 2,900 psi ) from lower pressure banks of oxygen and helium cylinders .
Each mix is bespoke and is created using gas blending techniques , which often involve the use of booster pumps to achieve typical diving cylinder pressures of 200 bar ( 2,900 psi ) from lower pressure banks of oxygen and helium cylinders .