White-Paper Details Ways to Avoid Combustible-Cloud Explosions
Recent studies covering facilities in the United States, UK and Germany show that controlling static electricity build-up is the key to preventing many combustible-cloud explosions.
A newly released white paper from Newson Gale, Inc. provides a practical study of combustible cloud fires and explosions, their genesis and the means to prevent them. The paper is now available, free of charge, for review or downloading, from the Newson-Gale, Inc. website: www.newson-gale.com/KnowledgeBase/KnowledgeBase.asp. or, alternatively go to www.newson-gale.com and click on the "Knowledge Centre" drop-down. No registration is required.
The paper is based on data provided in studies published by government-agency and insurance sources in the United States, the UK and Germany. A bibliography is included. All told, 281 explosions in the U.S. were identified as having been caused by ignitable combustible dust atmospheres in a 20-year study period. And, in one ten-year period an insurer reported $3.1 million total losses traceable to dust fires and explosions in the U.S.
Industrial process equipment is cited as the most likely source of an explosion or fire. This would include both actual processing and functions involving the transfer or transportation of components and end-products. And, in a large proportion of such instances, static electricity can be identified as the primary ignition source.
Significant among the processes most often subject to combustible cloud formation are: dust collection, powder grinding and pulverizing operations, powder conveying, silo and container filling, and general mixing or blending of powders. Among the products considered most likely to lead to the danger of an explosion or fire are zinc and other metallic powders, wheat flour and other food products and certain plastics and resins. In all of these cases, if unprotected, normal processing steps can produce enough static electricity to ignite a dust cloud.
The conclusion of the paper is devoted to discussions of how and in what circumstances static electricity buildup is likely to occur and what are the accepted means to avoid the danger of combustible cloud explosions or fires.
