【国外标准】 Standard Practice for Manual Sampling Coal from Surfaces of a Stockpile (Withdrawn 2003)

1.1 This practice covers procedures for obtaining a manual gross sample from the surface of coal stockpiles. These procedures are used to provide gross samples for general laboratory analysis and for estimating quality and total moisture. The gross sample is to be crushed and further prepared for analysis in accordance with Method D2013. Mechanical equipment such as auger samplers and core drill rigs are addressed by othe guides (D 4916) or working papers.1.2 The user is cautioned that samples of this type do not satisfy the minimum requirements for probability sampling and as such cannot be used to draw statistical inferences about the precision, standard error, or bias.1.3 This sampling method is intended for use only when sampling by more reliable methods that provide a probability sample is not possible.1.4 The quantities stated in either acceptable SI units or in inch-pound units are regarded separately as standard. The quantities stated in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining quantities in any way.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 and health practices and determine the applicability of regulatory limitations prior to use.