5.1 It is intended that this practice be used to provide a sample representative of the coal from which it is collected. Because of the variability of coal and the wide variety of mechanical sampling equipment available, caution should be used in all stages of the sample collection process, the design of sampling system specifications, the equipment procurement and the acceptance testing of installed equipment.

5.2 After removal from the sampling system and further preparation (Practice D2013 ), the sample may be analyzed for a number of different parameters. These parameters may define the lot's value, its ability to meet specifications, its environmental impact, as well as other properties.

1.1 This practice is divided into 4 parts. These 4 parts represent the previous standards D7256/D7256M , D4916 , D4702 , and D6518 . These 4 standards are the 4 that govern the mechanical sampling of coal and have been combined into one document for the ease of reference of the users of these standards.

1.2 Part AMechanical Collection and Within-System Preparation of a Gross Sample of Coal from Moving Streams Covers procedures for the mechanical collection of a sample under Classification I-B-1 and I-B-2 (Practice D2234/D2234M ) and the within-system preparation (reduction and division) of gross samples utilizing various components of the mechanical sampling system.

1.3 Part BMechanical Auger Sampling Describes procedures for the collection of an increment, partial sample, or gross sample of material using mechanical augers. Reduction and division of the material by mechanical equipment at the auger is also covered. Further manual or mechanical reduction or division of the material elsewhere shall be performed in accordance with Practice D2013 .

1.4 Part CQuality Management of Mechanical Coal Sampling Systems Is applicable to the quality management of cross-belt, falling stream, and auger sampling systems.

1.5 Part DBias Testing of a Mechanical Coal Sampling System Presents sample collection and statistical evaluation procedures for testing mechanical sampling systems (including auger systems), subsystems, and individual system components for bias. It is the responsibility of the user of this practice to select the appropriate procedure for a specific sampling situation.

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 and health practices and determine the applicability of regulatory limitations prior to use. For a specific hazard statement, see section 16.1 .