This part of ISO 16840 specifies apparatus, test methods and disclosure requirements for wheelchair seat cushions intended to maintain tissue integrity and prevent tissue trauma. It does not include test methods or requirements for determining the fire resistance of cushions. Annex B provides guidance on selecting cushions with appropriate fire resistance characteristics. This part of ISO 16840 does not address the interface pressure distributing characteristics of seat cushions nor the heat and water vapour dissipation characteristics of seat cushions that will be addressed in further parts of ISO 16840.

This part of ISO 16840 can also be applicable to tissue integrity management devices used as other support systems, as well as to cushions used in situations other than a wheelchair.