API 672:1996

Establishes the minimum requirements for constant-speed, packaged, integrally geared centrifugal air compressors, including their accessories. It may be applied for gas services other than air that are nonhazardous and nontoxic. This standard is not applicable to machines that develop a pressure rise of less than 0.35 BAR (5.0 psi) above atmospheric pressure, which are classed as fans or blowers.