When must quality control be performed when using a refractometer?

Question

Quizplus · Accepted Answer

Quality control should be performed before testing each specimen to ensure accurate and reliable results. This involves calibrating the refractometer with a known standard solution and checking for any errors or inconsistencies in the readings. Calibrating it at the beginning of the day may also be necessary, but it does not replace the need for quality control before each test. Comparing values with tap water is not a sufficient or reliable method for quality control.

When Must Quality Control Be Performed When Using a Refractometer