The American Society of Testing and Materials (ASTM) and the European Committee for Standardization (CEN) have promulgated similar pressure test methods to evaluate the overall gas-tight integrity of fully encapsulating garments. These test methods are contrasted by differences in pre-test conditioning pressures, settling times, starting pressures, and ending pressures. The purpose of this study was to determine the sensitivity of these pressure test methods to garments fabricated from film-based and elastomeric fabrics. Also included was a study to determine normal internal operating pressures measured during the ASTM F1154 standard form, fit, and function protocol. Test method sensitivity was assessed by determining the minimum diameter hole required to induce a failure according to the criteria specified in the relevant pressure test method. Hypodermic needles of specified sizes were used to create leaks in the test garments. Operating pressures were determined during the wear test by monitoring interior suit pressures at three sampling ports. Maximum internal pressures measured during this study appear to lay between those set by ASTM and CEN thus bringing into question, the relative severity and ultimate applicability of these methods.