This part of ISO 10542 specifies test methods and requirements for design and performance, instructions to installers and users, and product marking and labelling of wheelchair tiedown and occupant-restraint systems (WTORS). It is applicable only to WTORS that use clamp-type tiedown to secure wheelchairs when used as a forward facing seat by an adult passenger or driver of a motor vehicle. This part of ISO 10542 is applicable primarily to complete WTORS, but a portion of this part of ISO 10542 can also be applied to components and sub-assemblies sold separately and for replacement parts. This part of ISO 10542 is applicable to WTORS intended for use with all types of manual and powered wheelchairs, including scooters with three or more wheels.