Simplifying standards, opening restrictions Part I: The influence of the test vessel volume on the maximum explosion pressure of dusts

Explosion characteristics are widely used in the process industries to determine the potential hazard of the used substances. In the American and European standards for determination of the maximum explosion pressure of dusts, the measured pressure is corrected if the tests are conducted in the 20L-sphere. This correction formula increases the measured values if they are above 5.5 bar g. It also causes, that the only two volumes for testing that are used are the standard 1m³ and the 20L-sphere because it is unclear whether corrections are necessary and, if so, what correction should be applied at other volumes.

In this article explosion tests were performed with four different dusts, lycopodium, lignite, aluminum, and nitrocellulose, in four different vessel sizes: 20 L, 250 L, 365 L, and 1000 L to investigate the influence of the vessel size.