NBN ISO 21066:2021

This document specifies a method, the Resazurin (Rz) ink test, for the qualitative assessment of the
activity of a photocatalytic surface, and its classification as below, within, or above the applicable range
of the test. The method then allows for the subsequent semiquantitative evaluation of the activities of
photocatalytic surfaces that are within the applicable range of the test. In all cases, artificial ultraviolet
(UV) radiation is used.
The test method specified is appropriate for use with all flat, smooth, photocatalytic surfaces, which are
not macroporous, examples of which include: commercial photocatalytic glass, paint, tiles and awning
materials. The method is not applicable to assessing the visible-light activity of photocatalytic surfaces,
nor their ability to effect: air purification, water purification, self-cleaning or disinfection, although
some relevant correlations have been reported[4][5].