Facilitating consistent siting hazard distance predictions using the TNO Multi-Energy Model

• Current use of the Multi-Energy Model by analysts has many inconsistencies leading to variable results.
• This paper presents clear rule sets to assist different analysts achieve a more consistent application.
• These address common equipment layout and separation in refinery units.
• The method does not change the Multi-Energy method, instead it provides a clear application rule set.
• Applying these rules should allow different analysts to achieve consistent results for facility siting.

Facility Siting has received considerable attention in recent years. There are a number of generally accepted simplified methods for the prediction of vapor cloud explosion (VCE) blast loads, one of which is the Multi-Energy Model (MEM) (TNO, 2005). This paper presents an approach to improve the consistency in TNO MEM blast load predictions by providing explicit implementation guidance. A rule set was developed to improve the consistency with which key model parameters are determined. These rules incorporate no new science, but can be applied in a repeatable manner and are intended to reduce analyst variability and results which are more consistent with other approaches, such as the Baker-Strehlow-Tang (BST) method.