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Association, Inclusion

the result of a comparison between two hair samples in which the characteristics of the questioned hair are present in the known hair sample without any exclusionary differences and, therefore, the donor of the known sample can be included as a possible source of the questioned hair.

Discussion—A microscopical association of hair cannot identify the definitive source of a questioned hair to the exclusion of all others and the number of individuals who could be included as a possible donor of a specific hair is unknown and cannot be reliably estimated.

Committee
Trace Materials
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASTM E3175-23 Standard Practice for Training in the Forensic Examination of Hair by Microscopy. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2023. Source link
Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org