【国外标准】 Standard Practices for Sampling Wastes from Pipes and Other Point Discharges

4.1 The procedure outlined in these practices are guides for obtaining descriptive samples of solid, semisolid, and liquid waste from flowing streams, and incorporate many of the same procedures and equipment covered in the Referenced Documents. These practices by themselves will not necessarily result in the collection of samples representative of the total waste mass. The degree to which samples describe a waste mass must be estimated by application of appropriate statistical methods and measures of quality assurance. It is recommended that those practices be used in conjunction with Guide D4687.1.1 These practices provide guidance for obtaining samples of waste at discharge points from pipes, sluiceways, conduits, and conveyor belts. The following are included:  Sections     Practice A – Liquid or Slurry Discharges     Practice B – Solid or Semisolid Discharges 7–910–121.2 These practices are intended for situations in which there are no other applicable ASTM sampling methods (see Practices D140/D140M and D75/D75M) for the specific industry.1.3 These practices do not address flow and time-proportional samplers and other automatic sampling devices.1.4 Samples are taken from a flowing waste stream or moving waste mass and, therefore, are descriptive only within a certain period. The length of the period for which a sample is descriptive will depend on the sampling frequency and compositing scheme.1.5 It is recommended that these practices be used in conjunction with Guide D4687.1.6 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. See Section 5 for more information.1.7 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.