Astm E562-19e1 Today

Furthermore, the standard teaches an essential scientific discipline: how to convert qualitative observation into quantitative data with known statistical uncertainty. Whether you are certifying aerospace alloys, validating additive manufacturing porosity, or characterizing geological thin sections, ASTM E562-19e1 provides the rigor you need.

Then average over all fields:

[ s = \sqrt\frac\sum (\barV_V - V_V(field))^2n-1 ] astm e562-19e1