Traceability

property of a result of a measurement or value of a standard whereby it can be related with a stated uncertainty, to stated references, usually national or international standards through an unbroken chain of comparisons. Discussion—The concept is often expressed by the adjective traceable. The unbroken chain of comparisons is called a traceability chain (applicable only to the French text). Traceability of values in the certification of reference materials for chemical composition is discussed in IS0 Guide 35:1989 (Subclause 9.3.1) in which attention is drawn to the special problems associated with chemical analysis. Traceability of the chemical species is frequently of equal or greater importance than the traceability of the calibration of the instruments used in the analysis.