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UL CRS Decision Rule

 

A1 – If compliance means less than the limit

Situation Decision rule with the consideration of uncertainty of measurement
1 The measurement result is “PASS” if it is less than the limit value by adding or subtracting the uncertainty of measurement.
2 If the measurement result is less than the limit. With the consideration of plus/minus the expanded uncertainty with a 95 % coverage probability overlaps the limit, it is not possible to state compliance or non-compliance and report as “INCONCLUSIVE”.
3* If the measurement result is greater than the limit, the result is reported as “FAIL”.
4 The measurement result is “FAIL” if it is greater than the limit value by adding or subtracting the uncertainty of measurement

 

A2 – If compliance means greater than the limit

Situation Decision rule with the consideration of uncertainty of measurement
1 The measurement result is “PASS” if it is greater than the limit value by adding or subtracting the uncertainty of measurement.
2 If the measurement result is greater than the limit. With the consideration of plus/minus the expanded uncertainty with a 95 % coverage probability overlaps the limit, it is not possible to state compliance or non-compliance and report as “INCONCLUSIVE”.
3* If the measurement result is less than the limit, the result is reported as “FAIL”.
4 The measurement result is “FAIL” if it is less than the limit value by adding or subtracting the uncertainty of measurement

 

 

* Remark:

For situation 3 of the above tables, we implement a more precautionary approach for our clients. i.e. we reported fail where there is possibility** of passing with the consideration of measurement uncertainty (**<50% the expanded uncertainty with a 95 % coverage)