Abstract :
In the early 1980s, an iInternational round-robin was held in which the apparent
thermal conductivity of specimens of fibrous glass insulation board was
measured by users of guarded hot plates [GHPsl and heat-flow meters I HFMsL
The round-robin was performed over a period of several years by laboratories
in Europe, North America, Australia, and the Far East. Participants in this
round-robin were organized into 12 "loops," 8 for participants with GHPs and
4 for those with HFMs. Each !oop included laboratories located in the same
region of the world and sharing the same set of specimens. In an attempt to
obtain insight into the accuracy of the measurements, participants were also
asked to measure the thermal conductivity of a layer of air. The data submitted
in this round-robin are exhibited and analyzed. The overall agreement of
individual measurements with a least-squares fitted curve, as measured by one
standard deviation or, was a= 2.4% for GHPs and oʹ= 2.7% for HFMs. Suggestions
are made fur conducting future round-robins of this type.
