This document specifies strength requirements and test methods for wheelchair castor assemblies. The test methods include corrosion, abrasion and fatigue conditions. This document also specifies requirements for disclosure of test results. It applies to castor assemblies of or developed for use in occupant- and assistant-propelled manual wheelchairs and electrically powered wheelchairs. The test requirements also cover wheelchair castor assemblies not necessarily associated or supplied with a wheelchair. Castors including anti-tip castors that do not touch the ground during wheelchair travel are not included.