What does the precision statement in Method 10100 for Hypochlorite mean?

Document ID

Document ID TE5344

Published Date

Published Date 27/05/2017
Question
What does the precision statement in Method 10100 for Hypochlorite mean?
Summary
Precision statement in Method 10100 for Hypochlorite
Answer
In method 1011 for Hypochlorite, there is a precision statement that says one analyst received a standard deviation of ± 1.5 g/L (± 1.5%) Cl 2.

The 1.5 % value listed does not reflect units of concentration (1% is roughly 10,000 ppm), but denotes percent error. The analyst tested a bleach sample that was 91.2 g/L and multiple tests on that standard, received a standard deviation of ±1.5 g/L which is ± 1.5% of 91.2 g/L.