Development of a Computer Program for Permeation Testing Data Analysis

Abstract

A Microsoft Windows-compatible computer program, referred to as “Permeation Calculator,” was developed at the National Institute for Occupational Safety and Health (NIOSH) to automate and standardize permeation testing data analysis. The program imports the data file collected during a permeation test and calculates relevant permeation parameters within a few seconds, based on a series of algorithms, strategies, and automated decision-making processes. It allows calculations of all the permeation parameters related to American Society for Testing and Materials (ASTM) F 739, International Organization for Standardization (ISO) 6529, and ASTM D 6978 standards, including standardized breakthrough time, normalized breakthrough time, breakthrough detection time, steady-state permeation rate, cumulative permeation mass at a given elapsed time, and elapsed time at a given cumulative permeation mass for either a closed-loop or an open-loop permeation test. For open-loop permeation testing, the software also allows changing sampling flowrate and allows calculations of average permeation rate and maximum permeation rate to see if the rates ever reach the threshold maximum for decision making. On completion, the software displays all the permeation parameters together with relevant information and the permeation curve as a report file in Microsoft Excel and text file formats. This software helps industrial hygienists and researchers to avoid labor-intensive hand calculations of the permeation parameters. The software also prevents experimenter bias, thus ensuring identical permeation parameters will be obtained from a given permeation testing data file. The Permeation Calculator is available either on the NIOSH website or on CD by request.

Keywords:

• breakthrough time
• chemical protective clothing
• computer program
• permeation testing
• cumulative permeation
• permeation rate

ACKNOWLEDGMENTS

The authors gratefully acknowledge the contributions of Daniel Chung, a summer student from Carnegie Mellon University, for initiating the computer code.

Mention of commercial product or trade name does not constitute endorsement by the National Institute for Occupational Safety and Health (NIOSH). The findings and conclusions of this report are those of the author(s) and do not necessarily represent the views of NIOSH.