I have a standard solution to check accuracy with my colorimeter/ spectrophotometer or test kit, and keep getting zero. What is wrong?

Document ID

Document ID TE769

Published Date

Published Date 27/05/2017
Question
I have a standard solution to check accuracy with my colorimeter/ spectrophotometer or test kit, and keep getting zero. What is wrong?
Summary
Accuracy check shows a result of zero
Answer
Be sure to add reagents to the standard, just as if it were a sample. Color needs to develop in the standard solution the same way that it develops in the sample.Follow the step-by-step procedure but substitute the standard solution for the sample. For example, add the standard to the sample cell, add reagents, wait any timed steps, and then read the standard in the kit or instrument.