wtw PhotoLab Spektral Operating Instructions Manual page 86

9 Analytical Quality Assurance (AQA)
After the measurement is finished:
After successful light barrier testing, the PhotoCheck
standards (test solutions) are measured.
Example:
56
→ Insert the L2 cell.
→ Insert a cell with the test solution, 445-1.
The photometer measures the absorbance of the test
solution and compares the result with the value en-
tered.