Dictionary · Standards & Units
Certified reference material (CRM)
A reference material accompanied by documentation issued by an authoritative body providing property values with uncertainties and traceability using valid procedures — per ISO 17034 practice.
Related terms
More from Standards & Units
Kind of quantity
The aspect common to mutually comparable quantities — length, mass, and energy are kinds; diameter and wavelength are both quantities of the kind length.
VIM (JCGM 200:2012) 1.2
Quantity calculus
The set of mathematical rules applied to quantities rather than bare numbers — the algebra by which units propagate through equations.
VIM (JCGM 200:2012) 1.21
Ordinal quantity-value scale
A quantity-value scale for ordinal quantities, established by agreement on a procedure — comparisons of order are valid, arithmetic on the values is not.
VIM (JCGM 200:2012) 1.28
Coherent system of units
A system of units in which every derived unit is coherent — the SI as used with its base and coherent derived units.
VIM (JCGM 200:2012) 1.14
Coherent derived unit
A derived unit that is a product of powers of base units with no numerical factor other than one — the newton is coherent in the SI; the kilometre per hour is not.
VIM (JCGM 200:2012) 1.12
Standard reference data
Reference data issued by a recognized authority — the CODATA constants and NIST standard reference databases are the working examples.
VIM (JCGM 200:2012) 5.17