Over deze norm
1.1 This practice covers the reduction and division of gross or divided samples, and the preparation of composite samples, up to and including the individual portions for laboratory analysis.
1.2 Reduction and division procedures are prescribed for coals of the following groups:
1.2.1 Group A includes coals that have been cleaned in all sizes.
1.2.2 Group B includes all other coals. Unknown coals are to be considered under Group B.
1.2.3 Group A allows smaller weight laboratory samples to be retained than Group B. These lower weights may be used for particular coals if they have been shown, by using the procedures of , to give a sample preparation and analysis variance which is no more than 20 % of the total analysis variance.
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
1.4 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.
1.5 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.
|Nederlandse titel||Standard Practice for Preparing Coal Samples for Analysis|
|Engelse titel||Standard Practice for Preparing Coal Samples for Analysis|