The current equation (NFPA 68 eq. 8.9.2) to estimate fireball dimension is only valid for Kst ≤ 200 bar m/s, Pmax ≤ 9 bar and Pstat ≤ 0.1 bar. There are many common dusts with properties outside of these ranges and extension of the fireball equation beyond these ranges in needed to allow end users to properly define safe zones around explosion vents. Further, it needs to be noted that EN 14491:2012 - Dust explosion venting protective systems provides a slightly different method for estimating fireball dimensions and has different limits.
Research Goal: The aim of this project is to identify the existing fireball dimension estimation equations and the technical basis for existing limits in the conditions for their application. The project should also identify methods to extend NFPA 68 (2013) equation 8.9.2 to a broader range of Kst, Pmax and Pstat conditions.
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