规定了一种适用于硬纤维板的方法，其原理包括测量放置在试样表面上的测量头逸出的空气。该装置的细节如图所示，相关数值如表所示。

A method applying to hard fibre boards is specified, the principle of which consists in measuring the air escaping from measuring head placed on the surface of a test piece. Details of the apparatus are illustrated in figures and relevant values are given in a table.