This standard specifies the methods for determining the basic dimensions and skewness of paper and paperboard. For sheet paper, the standard requires the use of a steel tape measure with an accuracy of 1 millimeter and a length of at least 2 meters to measure its length and width. As for the width of reel paper, a vernier caliper with an accuracy of 0.02 millimeters is required for more precise measurement. In terms of skewness determination, the standard elaborates on a method that involves folding the sample or aligning two pieces of paperboard face-to-face and back-to-back, and then measuring the distance between specific points to calculate the deviation value. This method is generally applicable to various forms of paper and paperboard, such as sheets, rolls, and reels, but is not suitable for paper with surface wrinkles.