This document specifies a test method for investigating the oxidative stability of ultra-high-molecular-weight polyethylene (UHMWPE) moulded forms as a function of processing and sterilization method. This document describes a laboratory method for accelerated ageing of specimens taken from UHMWPE moulded forms or forms fabricated from these for use in the manufacture of surgical implants. The specimens are aged at elevated temperature and at elevated oxygen pressure, to accelerate oxidation of the material and thereby allow for the evaluation of its potential long-term chemical and mechanical stability.