O-169 Benefits of IM on Storage and Operations

With greater international interest on munitions safety it is important to identify the potential benefits of Insensitive Munitions (IM) when compared to conventional munitions. These benefits help to maintain the trend of improved IM development throughout the explosives community and reduced hazard during the lifecycle.

Within a munitions life cycle the two main areas where hazards and risks occur are during storage and on operations. It is therefore important to review the impact of IM in these areas, as these should be significant factors when choosing whether to procure munitions with reduced vulnerability and consequence.

This paper aims to identify the benefits by analysing standards for IM assessment, and by conducting two case studies; the first into an explosive accident where IM would have proved beneficial, with the second being a study looking into the differences between the physical effects and Quantity Distance (QD) regulations for HD1.1 munitions and IM for similar munitions natures.

Analysis of the results found the following conclusions:

The existence of different “IM” test standards leads to nomenclature confusion.

• Aspects of ageing and large scale storage offer a greater complexity than covered by assessment testing but have limited understanding.
• IM can offer reduced consequences in operational accidents but may not eliminate the possibility of an accident occurring.
• HD1.6 has more extensive test requirements than SsD1.2.3, but currently has the larger QD according to AASTP-1.
• Small Quantity QDs will have a future impact on both SsD1.2.3 and HD1.6, with respect to the quantification of the Maximum Credible Event (MCE).
• Harmonisation between QD regulations for HD1.6 and SsD1.2.3 needs to be improved and include SQQD rules.
• The way thermal effects are addressed in QD regulations for SsD1.2.3 and HD1.6 needs to be validated experimentally.
• In a cost benefit analysis, the benefits of HD1.6 over SsD1.2.3 will become clear when also the probability of an explosion reaction is considered.
• The KG-ET has the potential to be used to derive more detailed QDs
• Current aggregation rules in AASTP-5 mean that IM has no benefits in operational storage.
• Any benefits of reduced QDs or storage of larger NEQs must be balanced with the increased ‘Risk-to-Stock’.