This document specifies the characteristics to be measured of suspensions containing multi-walled carbon nanotubes (CNT suspensions). It includes the essential and additional characteristics of the CNT suspension, and the corresponding measurement methods. Characteristics specific to health, environmental and safety issues are excluded from this document. WARNING — The use of this document can involve hazardous materials, operations and equipment. It does not purport to address all of the safety or environmental problems associated with its use. The execution of this document is entrusted to appropriately qualified and experienced people.