规定了仪器设计的原则，以及确定建筑构件和工业用类似构件的实验室稳态热传输特性应满足的最低要求。没有指定特定的设计。还介绍了仪器、测量技术和必要的数据报告。主要用于实验室测量大型不均匀样本。不提供在试验过程中通过试样进行质量传递的测量。

Lays down the principles for the design of the apparatus and minimum requirement that shall be met for determination of the laboratory steady-state thermal transmission properties of building components and similar components for industrial use. Does not specify a particular design. Describes also the apparatus, measurement technique and necessary data reporting. Primarily intended for laboratory measurements of large, inhomogeneous specimens. Does not provide for measurements where there is mass transfer through the specimen during the test.