Résumé
Ballistic testing has been carried out on 150 samples of used soft body armour ranging from 2-17 years old submitted from twenty different Canadian police forces. The aim of this program is to investigate the performance of aged body armour to provide a scientific basis for an Aged Armour Replacement Protocol. Currently the replacement policies for body armour in various police forces range from five years to indefinite service. Ballistic tests were carried out according to an abbreviated version of the National Institute of Justice standard to which a bullet resistant panel was originally certified. Eighteen panels allowed bullet perforation (12%) under the NIJ certification protocol of which three panels (2%) failed below the absolute minimum speed as indicated on the stitched label. However, if these results are considered in terms of the most recent NIJ 0101.06 standard where a degradation margin is allowed, they remain acceptable. Products displaying good performance at 13-17 years and others failing at 3 years suggests that the initial design and construction of body armour might play a greater role in bullet resistance than simple ageing.