O-040 IM Testing - Response Descriptors

This paper is a summary of the discussions and conclusions of the 1997NIMICWorkshop on IM Testing, Phase One, Working Group on Response Descriptors.

Currently, IMassessmentsmainly rely on a series of full scale tests. The results fromthese tests are ranked according to a scale of Response Descriptors. The objective of this paper is to analyse these Response Descriptors and make proposals regarding their evolution. Questions like how many and which Response Descriptors are needed, whether or not to define them more quantitatively, how to rate potential propulsion of the tested item, are dealt with.

The Group proposed that the Response Descriptors should be expressed in a quantitative and absolute way. What they should measure is the violence of the Response of a munition, in terms of the events that can induce damage to personnel and structures. The Group agreed that a good yardstick to rate these events would be serious-injury-to-personnel thresholds, and proposed values for these thresholds.

The approach taken would enable one to express each Response Type as follows: "no risk of serious injury to personnel beyond a certain distance from the explosive event." Some proposals regarding these distances, which are the only variable needed to discriminate Response Descriptors from one another, were also made.

The proposals constitute significant changes, and can be viewed as a philosophy shift. Consequently, Phase two of the Workshop, to be held in November 1997, should include some feedback from participating Nations, NATO AC/310, Hazard Classification authorities about them.

Phase Two will focus on confirming the quantitative thresholds proposed. Feasibility of the proposals needs to be studied inmore detail, in conjunctionwith test engineering experts. The end goal for Phase two will be to draft proposals for new Response Descriptors.