DIN 53145-2:2012-03

This document - as far as it concerns methods and measurement instruments - is in line with International Standard ISO 2469:2007 "Paper, board and pulps - Measurement of diffuse radiant factor". The document differs from ISO 2469 in particular in the following: In accordance with ISO 2469, reference standards with known spectral reflectance factors are provided by authorized laboratories. They are carried out in accordance with ISO by CEPI (Confederation of European Paper Industries) for the EU countries. According to 5.3, all calibrated white standards can be used. These can be manufactured from, for instance, opal, ceramics, PTFE or barium sulfate. The absolute reflectance factors shall be traceable to a national metrological laboratory. Absolute accuracy achieved during measurement of fluorescent papers is lower than absolute accuracy of non-fluorescent papers as spectral distribution of radiation of the light falling on the sample surface has a significant influence on the measurement result and this can vary from one device to another.