Significance and Use 5.1 Data analysis for chemical protective clothing permeation testing involves a number of equations and experimental factors. Possible calculation errors are critical issues when determining permeation parameters. Because the calculations of some of the permeation parameters are mathematically complex, this computer program will be useful. 5.2 This practice is to help researchers and industrial hygienists avoid labor intensive hand calculations of the permeation parameters. From a standardization point of view, this practice prevents variability or inconsistency caused by different experimenters thus ensuring identical permeation parameters or results will be obtained from a given permeation test data file. 5.3 Protective clothing manufacturers worldwide will benefit since they must inform customers about the permeation parameters of their products in a consistent manner. The practice will also help diagnostic laboratories and research centers involved in the chemical protective clothing testing.Scope 1.1 This practice covers the calculations of all the permeation parameters related to Test Method F739, ISO 6529, and Practice D6978 standards by use of a computer program, referred to as “Permeation Calculator” (DHHS (NIOSH) Publication No. 2007 – 143c).2,3 1.2 The practice is applicable to both open loop and closed loop permeation tests. The closed loop test includes continuous sampling and discrete sampling. The discrete sampling includes tests when sample volume is replaced and also when sample volume is not replaced. For an open loop permeation test, the computer program also allows permeation data files with variable sampling flow rate. Refer to Test Method F739 for more details about the different types of the permeation testing systems. 1.3 This practice is applicable to the most typical permeation behavior, that is, Type A, where the permeation rate stabilizes at a “steady-state” value. It does not apply to the other types of permeation behaviors. Refer to Test Method F739 for more details about the various permeation behaviors. 1.4 This practice is not applicable to Test Method F1383 because the permeation behavior is different under conditions of intermittent contact than under conditions of continuous contact. 1.5 This practice does not address the procedure of permeation testing. Refer to Test Method F739, ISO 6529, or Practice D6978 for the procedures in detail if needed.
