The precision of this test method as determined by
statistical examination of interlaboratory results is as follows:
13.1.1 For sulfated ash levels between 0.005 and 0.10
mass %.
13.1.1.1 Repeatability—The difference between two test
results obtained by the same operator with the same apparatus
under constant operating conditions on identical test materials
would, in the long run in the normal and correct operation of
the test method, exceed the following values only in one case
in twenty:
r 5 0.047 X0.85 (3)
where X = average of two results.
13.1.1.2 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 values in only one case
in twenty:
R 5 0.189 X0.85 (4)