P =(2 St/D )* F*E*T
P =Design pressure in pounds per square inch (kPa) gauge.
S =Yield strength in pounds per square inch (kPa) determined in accordance with §192.107.
D =Nominal outside diameter of the pipe in inches (millimeters).
t =Nominal wall thickness of the pipe in inches (millimeters). If this is unknown, it is determined in accordance with §192.109. Additional wall thickness required for concurrent external loads in accordance with §192.103 may not be included in computing design pressure.
F =Design factor determined in accordance with §192.111.
E =Longitudinal joint factor determined in accordance with §192.113.
T =Temperature derating factor determined in accordance with §192.115.
49 C.F.R. §192.105