3 ms·
As I understand it, each and every sample isn't necessarily uniform bur rather each sample is characterized and qualified by a NIST lab and a certificate of ana
by voxadam 4y ago
As I understand it, each and every sample isn't necessarily uniform bur rather each sample is characterized and qualified by a NIST lab and a certificate of analysis (COA) is supplied with each sample. This allows tier 2 and lower labs to verify that their equipment and analyses are within spec.
- samatman 4y agoThere are exact standards both for the accuracy of the reference material and the precision of the COA. So NIST can work backward, using faster tests to confirm that the material has suitable qualities to represent, say, 2% milk, then take the precise measurements for the actual batch of sample, which of course will vary.