I have a question regarding the definition and wording of the word working standard / primary standard.
For example: we have a lot of substances, we use as a quantitative reference for the regular quality control and batch release. Now these substances are in house qualified standards. These substances are mostly taken from former batches. Now my question is: can I call these reference standards a in house qualified primary standard? I understand that a working standard is qualified against a primary standard for example. But what If i don’t have a primary standard?
The wording is sometimes very complicated. So thank you very much in advance for any help in the clarification.