Classification of Dusts

KST (bar.m/s)CharacteristicsClass
KST ≤ 200Weak explosionSt. 1
200 < KST ≤ 300Strong explosionSt. 2
KST > 300Strong explosionSt. 3

KST value is now used extensively in designing plant explosion relief and suppression systems. Pmax is used in explosion containment design. In the US, NFPA 68 “Guide for Venting Deflagrations” (1998) provides guidance on results and interpretation.

eStrip® GPX media and various plastic abrasive media have KST values ≤ 200 bar.m/s, and thus fall within category St. 1. Consequently the same precautions and engineering controls should be applied to these abrasive products.