Volume fraction (vol.fr.) - Dynamic NPU Manual

Volume fraction (vol.fr.)



Definition in words

The volume of component B divided by the volume of system 1

Definition by equation

Result type

Rational scale
  • Value sets are positive numerical values (a=nb; a≠nb)
  • Algebraic operations are allowed
Numerical values from 0-∞


 10-18, 10-15, 10-12, 10-9, 10-6, 10-3, 1 (one), etc.

Special rule(s) in the NPU syntax

Unit, one (1) is omitted in the NPU syntax


Ferard G, Dybkaer R, Fuentes-Arderiu X. Compendium of Terminology and Nomenclature of Properties in Clinical Laboratory Sciences : Recommendations 2016. 1 ed: Royal Society of Chemistry; 2016. 182 p.

Laboratory field


Clinical Chemistry

Example 1
Generic abbreviated
NPU01961 B—Erythrocytes; vol.fr. = ?
Full result NPU01961 Blood—Erythrocytes; volume fraction = 0.45
Abbreviated result NPU01961 B—Erythrocytes; vol.fr. = 0.45
Written expression The volume fraction of Erythrocytes in Mr. Smith’s Blood is [0.45].

Example 2
Generic abbreviated
NPU03008 Air(expired)—Oxygen(O2); vol.fr. = ?
Full result NPU03008 Air(expired)—Oxygen(O2); vol.fr. = 0.16
Abbreviated result NPU03008 Air(expired)—Oxygen(O2); vol.fr. = 0.16
Written expression The volume fraction of Oxygen(O2) in Mr. Smith’s Blood is [0.45].

Clinical Toxicology

Example 3
Generic abbreviated
NPU16666 Beverage(spec.)—Ethanol; vol.fr. = ?
Full result NPU16666 Beverage(specification)—Ethanol; volume fraction = 0.11
Abbreviated result NPU16666 Beverage(spec.)—Ethanol; vol.fr. = 0.11
Written expression The volume fraction of Ethanol in Mr. Smith’s Beverage(specification) is [0.11].

“Beverage(specification)” is a system related to the patient.

The beverage needed to be specified by the laboratory.

Thrombosis and Haemostasis

Example 4
Generic abbreviated
NPU01694 B—Coagulum retraction; vol.fr.(proc.) = ?
Full result NPU01694 B—Coagulum retraction; volume fraction(procedure) = 0.25
Abbreviated result NPU01694 B—Coagulum retraction; vol.fr.(proc.) = 0.25
Written expression he volume fraction of Coagulum retraction in Mr. Smith’s Blood is [0.25].


NPU database, https://www.ifcc.org/ifcc-scientific-division/sd-committees/c-npu/npusearch/ and http://www.labterm.dk/default.aspx
  • Kind-of-property

    • Nominal kind-of-property

    • Kind-of-quantity

      • Unitary kind-of-quantity

        • Rational unitary kind-of-quantity

          • Volume fraction


  • Dybkaer R. Concept system on ‘quantity’: formation and terminology. Accredit Qual Assur. 2013;18(3):253-60.
  • Dybkaer R. ISO terminological analysis of the VIM3 concepts ‘quantity’ and ‘kind-of-quantity’. Metrologia. 2010;47(3):127-34.
Date Term Note
1996-01-01 Volume fraction Term established