30 CFR § 7.104 - Internal static pressure test.
(a) Test procedures.
(2) Internally pressurize each segment of the intake system or exhaust system to four times the maximum pressure observed in each segment during the tests of § 7.100, or 150 psig ±5 psig, whichever is less. Maintain the pressure for a minimum of 10 seconds.
(b) Acceptable performance.
(i) Leakage through welds and gasketed joints; or
(ii) Leakage other than along joints meeting the explosion-proof requirements of § 7.98(q).
(i) Changes in fastening torque;
(ii) Visible cracks in welds;
(iii) Permanent deformation affecting the length or gap of any flame-arresting paths;
(iv) Stretched or bent fastenings;
(vi) Permanent distortion of any planar surface of the diesel power package exceeding 0.04-inches/linear foot.