ASTM D4049 Standard Test Method for Determining the Resistance of Lubricating Grease to Water Spray
12. Report
12.1 Report the following: date, grease identity, and percent spray-off to the nearest 1.0 %.
13. Precision and Bias
13.1 The precision of this test method as determined by statistical examination of interlaboratory results in accordance with Practice E691 is as follows:
13.1.1 Repeatability - The difference between two test results obtained by the same operator with the same apparatus under constant operating conditions on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following value in only one case in twenty:
6.0 % spray-off
13.1.2 Reproducibility - The difference between two single and independent results obtained by different operators working in different laboratories on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following value in only one case in twenty:
18.0 % spray-off
13.2 Bias - The procedure for measuring a grease's resistance to water spray has no bias because the value of spray-off can be defined only in terms of a test method.
14. Keywords
14.1 grease; spray; water resistance; waterspray
