4.1 This test method can be used to quantify and compare the evaporative resistance provided by different clothing systems. The evaporative resistance values for ensembles measured under isothermal conditions can be used in models that predict the physiological responses of people in different environmental conditions. Garment evaporative resistance values can be compared as well (see Annex A1).

4.2 The measurement of the evaporative resistance provided by clothing is complex and dependent upon the apparatus and techniques used. It is not practical in a test method of this scope to establish details sufficient to cover all contingencies. Departures from the instructions in this test method have the potential to lead to significantly different test results. Technical knowledge concerning the theory of heat transfer, moisture transfer, temperature, humidity, and air motion measurement, and testing practices is needed to evaluate which departures from the instructions given in this test method are significant. Standardization of the method reduces, but does not eliminate, the need for such technical knowledge. Report any departures with the results.

1.1 This test method covers the determination of the evaporative resistance of clothing ensembles. It describes the measurement of the resistance to evaporative heat transfer from a heated sweating thermal manikin to a relatively calm environment. Information on measuring the local evaporative resistance values for individual garments and ensembles is provided in Annex A1.

1.1.1 This is a static test that provides a baseline clothing measurement on a standing manikin.

1.1.2 The effects of body position and movement are not addressed in this test method.

1.2 The evaporative resistance values obtained apply only to the particular ensembles evaluated and for the specified environmental conditions of each test, particularly with respect to air movement and sweating simulations.

1.3 Evaporative resistance values reported in SI units shall be regarded as standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.