5.1 The measurement of total moisture is required to determine whether coal meets commercial or environmental specifications, or both. Within the limitations prescribed in the scope, this practice describes a procedure for determination of total moisture that requires less time than the procedures described in Test Method D3302/D3302M.
Область применения1.1 This practice covers a single-stage procedure for the determination of total moisture less than 15 % in coal reduced to 2.36 mm [No. 8 sieve] topsize. This practice is for determination of total moisture only. Materials subjected to this test shall not be used in the determination of other test parameters. It is recognized that the conditions of the test can increase the potential for significant oxidation effects on some coals. If the oxidation potential is of concern, the use of this single-stage method shall involve prior agreement between the parties involved. This practice shall not be construed as the referee standard practice for total moisture. For referee purposes, users of this practice are referred to Test Method D3302/D3302M for moisture determination methods which are not as susceptible to oxidation effects.
1.2 Statistical analysis of data from several sources indicates that at a 95 % confidence level, there is statistically no difference between the mean value of the results obtained by Practice D2961/D2961M and Test Method D3302/D3302M (that is, no bias is detected between the two methods at the 95 % confidence level) for moisture levels between 1.4 % and 15.8 %. These two standards were not compared in this study for some ranks of coal including lignite and anthracite.2
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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.
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.