The technical durability, i.e. ballistic protection, optical reflection and flammability, for body armour 90 and 94 (krsk 90 and 94) was investigated. It was established that the protective vests still have satisfactory functions according to the requirements that was stated at the time of procurement. The work also included a study on requirements, standards and a literature survey of the effect of ageing and decomposition of para aramids. Ballistic protection, visual and IR signatures as well as flammability was assessed according to the requirements stated at the procurement and was tested according to the given standards. Should the procurement been done today other requirements would have been stated given the development on the threat area. FOI's opinion is that the protective vests will fulfil the required ballistic protection and have an acceptable camouflage ability in visual and NIR spectrum until the protective system is no longer in use for other reasons. The flame retardant seem to remain in vests with outer shell made of cotton, but is inferior in those made of polyamide. As it seem not to be any deterioration in the protection capability for vests older than 20 years, which also are well-worn, the conclusion is that it will not change during the coming 20 years either (if the outer shell still is intact). The ballistic protection will probably remain unaffected until the vests will be discarded for other reasons. The durability of this protection system will thus be determined by it's over all condition rather than any of the technical functions tested in this work. This report is a summary of the results that are presented in full in FOI-RH-- 1737--SE.