Rationale: The two corrections currently used for Method B External sample preparation in ASTM C1702 are viewed as cumbersome, labor- and sample intensive. Furthermore, the recently conducted Round Robin study of ASTM C1702 did not reveal any improvement in the resulting data when the current corrections were applied to method B. However, rather than eliminating the current correction factors altogether without any other changes to method B, the sub committee feels that some simple provisions are needed to ensure that the error induced through thermal exchange when samples are prepared externally is minimal: This would be achieved by specifying in Method B: (1) Pre-conditioning of materials to the same temperature as the calorimeter, (2) mixing inside sample vial for reduced time of mixing, minimized heat exchange during handling outside of the calorimeter, and eliminated error in cement content due to paste segregation.
Citing ASTM Standards
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