assay measures characteristic 2023-05-23T15:24:15Z A mass measurement assay measures an material's mass characteristic. A radioactivity detection assay measures the amount of radiation (alpha, beta or gamma ray emmissions) coming from a material. A relation between an assay and a characteristic, in which the assay generates a data item which is a measure of a characteristic. characteristic measured by assay specifically dependent continuant assay Damion M Dooley