This method presents: a) a statement on the precision and accuracy of measurements and an outline of a method for attaching a confidence interval to a calculated average, and b) procedures for determining the number of specimens to be chosen for a particular test. Because of the subject matter covered, this method differs in form from others in CAN/CGSB-4.2, Textile Test Methods; it has been designated as CAN/CGSB-4.2 No.1-M simply for identification and to conform with the general layout adopted.