【国外标准】 Standard Practice for Sampling and Preparation of Fresh or Salt-Preserved (Cured) Hides and Skins for Chemical and Physical Tests

3.1 The sampling procedures described in this practice have been designed to ensure random sampling of salt-preserved hides and skins for physical and chemical tests. Fresh or salt-preserved hides are natural products and as such are subject to extensive variability. The physical and chemical properties vary considerably depending on location on that specific hide, side, or skin from which the test sample is taken. Random sampling of specimens from a predefined location and orientation minimizes test bias and variability. This practice defines these parameters.3.2 In general, tests carried out upon fresh or salt-preserved hides require composite lot samples generated using the preparation methods described within this practice. Subsequent tests typically require those composite samples to be in two forms:3.2.1 Expressed Hide Fluid—where residual hide fluid is pressed from cleaned individual hair-on or de-haired hide sample, then equal volumes of each extracted fluid are blended together to create the composite sample.NOTE 1: Sample may be de-haired prior to pressing.3.2.2 Hide Material Sample—where equal quantities of cleaned hair-on or de-haired hide material are blended together to create a representative composite sample.NOTE 2: Samples may be de-haired prior to compositing.1.1 This practice covers the sampling and preparation of fresh or salt-preserved (cured) hides for physical and chemical tests. The hides or skins to be tested are grouped into lots. Each lot is randomly sampled in such a manner as to produce a representative sample of that lot. This lot sample may be used to determine compliance of the lot with applicable specification requirements, and on the basis of results, the lot may be accepted or rejected in its entirety.1.2 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.1.3 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.1.4 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.