O-125 IM Response descriptors - An update for assessment processes

The need for assessment authorities to accurately review and pass judgment on the results of limited IM testing calls for an examination and updating of the current IM response descriptors. Historically, the basis for determining the IM signature of a munition system is a testing program which is normally limited to only a few full-scale IM tests. The definitions for the levels of response serves as a yardstick with which to measure the level of reduced vulnerability to specified threat stimuli. There needs to be a measure of flexibility in determining those responses based upon the evidence available. There has, however, been some concern over the consistency of the final judgment because in many cases a definitive measurement is not available.

NIMIC workshops held in the 1990’s addressed the response descriptors definitions cited in STANAG 4439 and AOP-39. Two technical meetings sponsored by MSIAC were held in 2008 to bring together international experts in the areas of IM and IM testing in response to a NATO AC/326 Subgroup 3 request. These follow-up technical sessions build upon prior international collaboration that sought to improve the IM assessment process as a recognized international standard. Their principal objective was to review the current IM response descriptors and formulate recommendations to update the descriptors used for IM and hazard classification assessments. Discussions assessed the relevance of the current response descriptors and examined the need for change to incorporate any improvements based on test and evaluation experience and state-of-the-art test methods. The participants considered test procedures, recent experiences, and data related to real tests and determined if desirable changes to the assessment criteria. This paper will present the result of these technical meetings and summarize proposed new response descriptors for future implementation.