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CRS Decision Rule for UL UK CRS Customers with testing performed in the UK (Version 2.1)

1. When it is required to have a statement of conformity to a specification or standard of test, the laboratory’s decision rule will be communicated to and agreed by the customer through the testing request form, or test service agreement, or quotation, or program documentation, or email communication.

 

2. The Decision Rule determination flow

a. When the decision rule is inherent in the regulation or standard, the inherent decision rule will be followed.

b. When the decision rule is prescribed by the client and accepted by the laboratory, the prescribed decision rule will be followed.

c. The UL CRS Decision Rule — UK will be applied for other cases.

 

3. The UL CRS Decision Rule — UK

DR1. For non-numerical testing results, the statement of conformity will be reported by comparing the testing results and the specifications, or requirements AND the measured value of the testing conditions plus or minus the expanded uncertainty with a 95% coverage probability are within the specifications, or requirements and measurement conditions. The risk of test conditions to be outside the specification is no greater than 5%.

DR2. For numerical testing results, the statement of conformity will be reported by comparing the testing results plus or minus the expanded uncertainty with a 95% coverage probability and the specified limit in the specifications, or requirements. If the testing results plus or minus the above expanded uncertainty overlaps the limit, no declaration of conformity can be made. The specific false accept or reject risk is no greater than 5%.