A self-contained breathing apparatus includes an air cylinder pressurized to about 5500 psig, wherein the air cylinder is compatible with infrastructure used in conjunction with the air cylinder. The self-contained breathing apparatus also includes a first regulator valve for reducing air pressure from the air cylinder to a predetermined level. A second regulator valve is also provided for reducing the air pressure from the predetermined level to a level suitable for use by an operator, wherein air is supplied from the second regulator valve to the operator via a mask. The self-contained breathing apparatus further includes a frame for supporting the air cylinder on the back of the operator. Other embodiments are described and claimed.