DISCLAIMER: This is a “cheat sheet” for safety professionals to get a general idea of the “safe distances.” ALWAYS refer to ASME PCC-2, Mandatory Appendix 501-III) for the exact distance. Just understand, ALL pneumatic pressure testing REQUIRES a “safe distance”.
According to ASME PCC-2, Mandatory Appendix 501-III, determining safe distances for pressure testing—specifically, pneumatic testing—requires calculating the system’s stored energy. While hydrostatic testing distances are generally much smaller, pneumatic testing distances are based on the potential energy release (TNT equivalent) of the compressed gas.