Abstract

Standard reference materials within the European Community are developed by the "Bureau Communautaire de Reference. " The development of reference materials for the measurements of steady-state thermal transmission properties was started in 1975 with two candidates: a high-density resin-bonded glass-fibre board and Pyrex. The first is now the reference material RM 64, certified be-tween 170 and 370 K. The second candidate, Pyrex, is still under investigation, first of all to find a reliable procedure to correctly define the surface temperatures of specimens under test. Only recently it was decided to develop a reference material for measure-ments on light-density fibrous insulations that exhibit a relevant so-called thickness-effect. Investigations started on a 10 kg/m3 organic fibrous material. The reason for this preliminary choice was the large thickness-effect of the material and its acceptable homogeneity; the main limit of this material is its