ASTM D5828 Standard Test Method for Compatibility of Supplemental Coolant Additives (SCAs) and Engine Coolant Concentrates
10. Report
10.1 Report the volume insolubles in millilitres for the test mixture, the volume insolubles in millilitres for the reference mixture, and the ratio calculated in 9.2.
11. Precision and Bias
11.1 Precision - The precision of this test method as determined by an interlaboratory round robin performed in accordance with Practice E691 has been determined to be dependent upon the test level and may be estimated as follows:
Repeatability (r) = 0.12341X
Reproducibility (R) = 0.31641X
where X = average of two results being compared.
11.1.1 In the long run, the average of two results determined on identical materials by the same operator following this procedure in the same laboratory using the same equipment on the same day will exceed the repeatability only once in twenty times. Similarly, the average of two results determined by two different laboratories on random samples of the same batch of identical materials will exceed the reproducibility only once in twenty times.
11.2 Table 1 shows the range of ratios determined in the round robin. The volume of insolubles measured on the reference materials was in the range from 0.30 to 0.80 mL.
11.3 Bias - No information is available on the bias of the procedure in this test method since the compatibility of all materials is determined in relation to a set of standard reference materials.
12. Keywords
12.1 engine coolants; supplemental coolant additives (SCA)
