19 January 2016
In chemical suit selection a “breakthrough” result (commonly >480 minutes) from a permeation test is often interpreted as meaning “it takes more than 480 minutes for the chemical to break through the fabric, so I am safe in this suit for 480 minutes”.
However, this is not what it means at all. The definition of the “Breakthrough” is “the time taken for the permeation rate (ie the speed that permeation occurs) to reach 1.0µg /Min/cm2. So at the breakthrough point, the chemical has already been permeating through the fabric.
This is one reason why the standard states in its introduction that permeation testing should be used ONLY for fabric comparison and NOT to give any indication of a “safe-use” time.
Lakeland’s new Permasure app for use with ChemMAX chemical suits solves this problem. An on-line app for use with ChemMAX chemical suits, it provides users with actual safe-use times based on the exposure time, the temperature and the toxicity of the specific chemical – selected from over 4000 options.
Permasure is a tool that allows safety managers involved in chemical suit selection to manage specific applications more effectively as part of a more effective risk assessment. It is available for free from Lakeland. Contact email@example.com for more information.