Experimental Guidelines

Using blast engineering approaches and analysis, we have developed guidelines to inform the design of appropriate blast loading conditions used in primary blast injury experiments.

This work has resulted in two publications:

1. “Defining blast loading ‘zones of relevance’ for primary blast injury research: A consensus of injury criteria for idealised explosive scenarios” Medical Engineering Physics.

Work to define blast loading conditions for injury research has received relatively little attention, though with a continued experimental focus on primary blast injury (PBI) and idealised explosion assumptions, meaningful test outcomes and subsequent clinical applications, rely on appropriate simulated conditions. This paper critically evaluates and combines existing PBI criteria (grouped into those affecting the auditory system, pulmonary injuries and brain trauma) as a function of idealised blast wave parameters.

Highlights from the article include:

•There lacks consensus in the application and assumptions of PBI predictive criteria.

•Existing PBI criteria can define zones of clinically-relevant blast wave parameters.

•Application of PBI criteria could support clinical response to explosion incidents.

•Further work is needed to define blast exposure thresholds for mild blast traumatic brain injury (bTBI).

See the full article at: https://doi.org/10.1016/j.medengphy.2021.05.014

2. “Guidelines to inform the generation of clinically relevant and realistic blast loading conditions for primary blast injury research” BMJ Military Health.

At present, there are no guidelines specifically for the design or specification of appropriate blast wave parameters within experimental primary blast injury (PBI) studies. Through analysis of PBI criteria and theoretical blast wave calculations, zones of blast parameters are proposed to guide experimental designs.

Key messages include:

•The range of blast conditions of relevance to PBI research is limited, prompting reason for researchers to consider whether loading conditions are appropriate.

•While many experimental loading conditions are achievable, this analysis demonstrated limits that should be observed to ensure loading is clinically relevant, realistic and practical.

•To simulate loading conditions found outside the fireball and of clinical relevance to PBIs, generated blast waves should correspond to blast scaled distances 1.75<Z<6.0.

•Blast waves with positive phase durations (2-10ms) are typically more practical to achieve, while representing realistic threats such as IEDs (i.e. 1-50kg TNT equivalent).

See the full article at: http://dx.doi.org/10.1136/bmjmilitary-2021-001796

For more information or collaboration, contact Dr Jack Denny (Jack.Denny@soton.ac.uk).