【国外标准】 Standard Practice for Core Sampling of Raw Wool in Packages for Determination of Percentage of Clean Wool Fiber Present

5.1 Core sampling is widely accepted, when applicable, for obtaining a laboratory sample representative of the clean wool fiber present in a lot of packaged raw wool.5.2 If the wool is so loosely packed that a core cannot be cut, or if it is so highly compressed that the sampling tool cannot readily penetrate into the package to the required depth and in the required direction, core sampling is not applicable. The density of wool in most types of commercial packages is suitable for sampling by this method.5.3 The procedure described in this practice is adapted to the application of statistical methods for estimating the size of sample required to achieve a required level of sample precision at minimum cost.NOTE 1: The basic sampling equipment, operating procedure, and statistical approach used in this practice have been adapted for sampling lots of wool for the determination of other properties that are not affected by boring, such as average fiber diameter, and for sampling lots of other bulk fibers in packages.FIG. 1 Small Diameter Wool Sampling Tool (United States Customs Service)(Metric equivalents may be calculated by multiplying inches by 25.4 to obtain equivalent dimensions in millimetres.)1.1 This practice for sampling covers a procedure for obtaining samples from lots of grease, pulled, or scoured wool or related animal fibers in bales or bags for the determination of the clean wool fiber present by a procedure similar to that described in Test Method D584.1.2 This practice provides a description of suitable core sampling equipment, the sampling procedure, and the method for determining the number of packages to be bored and the number of cores to be taken from each sampled package.1.3 Reliable estimates are given for the standard deviation of the percentage clean wool fiber present between packages and within packages for lots of many types of raw wool.1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.