March 10, 2010

Summing up the “perm” Series

by Bob Murphy

Final Odds ‘n’ Ends There are four things you should always ask yourself when evaluating competitors’ data or even comparing one set of data to another: What test method was used? ASTM D1653? E96? Some other method? Dry cup or wet cup? Are the terms the same? Am I comparing WVT to WVT or WVT […]

February 1, 2010

Terms of Confusion Part 2 Permeability Test Methods

by Bob Murphy

The Test Methods D1653 vs. E96 There are two primary ASTM test methods used to calculate the passage of water vapor through materials: ASTM D1653, Water Vapor Transmission of Organic Coating Films and ASTM E96, Water Vapor Transmission of Materials. Often times, you’ll see them referred as D1653-08 or E96-05. In ASTM convention, the number […]

January 20, 2010

Terms of confusion, Take 2

by Bob Murphy

Chemical resistance is one the most important qualities in protective linings in relation to protecting the infrastructure. Permeability is often overlooked aas a criteria for chemical resistance of protective linings “What’s the difference between transmission, permeance, and permeability?! I thought there were just ‘perms’.” Don’t worry – I’ll get to all of that later, but […]

October 8, 2009

Testing of Coatings and Linings in Wastewater Environments

by Bob Murphy

New coating and lining formulations are being developed to meet current performance needs and also future environmental regulations. The time is takes from original concept to possible formulation to commercialization is being compressed. Evaluation of the new formulations for coatings and lining used in harsh wastewater environments can be a daunting task. The standard practice […]