(8b) A Comprehensive Approach to Hazardous Area Classification for Combustible Particulate Solids

Combustible dust fires and explosions continue to negatively impact manufacturing processes and supply chains globally due to their ability to result in fatalities, equipment damage and structural failures (facility collapse). Bulk solids handling processes face a multitude of challenges when it comes to identifying potential causes of fires and explosion and then identifying practical solutions for risk mitigation. While there are multiple ways to prevent fires and explosions, one of the most obvious, and challenging, is the control of sources of ignition. A comprehensive Hazardous Area Classification (HAC) Assessment is the perfect place to start when using control of sources of ignition as a basis of safety.

Are all HAC’s the same? Are there “must do” elements of the assessment? Do I have to follow consensus standard guidelines?

A comprehensive HAC assessment involves analyzing critical process, equipment and material properties under normal operations, maintenance tasks and upset conditions. Assessors should always begin with the protocols outlined in NFPA 499 - Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, however, that is only the beginning of your journey.

This paper will discuss the importance of, and ways to, assess aspects of your process, equipment, materials, and even maintenance records to arrive at the most definitive and defensible HAC classification for your production processes.