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In this revision, the following major changes have taken up:
The test procedure has been updated to include two options for sample selection:
a) Volume-based sampling, that is using the weight equivalent to a 75 cm³ sample, or
b) Weight-based sampling, using a 50 g sample.
The volume-based method is preferred, as it minimizes errors associated with high ash or high mineral content. Indian coals typically exhibit a wide range of ash content, and volume-based sampling yields more accurate and consistent data. This approach is particularly beneficial for samples with varying mineral compositions, such as carbonaceous coal and shaly coal.
Additional apparatus, such as drying ovens and sample dividers, have been incorporated. While, improvements have also been made in balancing, sieving, and gross sampling processes, although the calculation method remains unchanged.
Regarding precision, the revised terminology included a requirement probability greater than 90% in both inter-laborat |