We need to start by clarifying terminology to understand what is mandatory or not. In the context of an accredited management system such as ISO 17025:2017, “having”, “considering”, “ communicating”, “defining”, “documenting” and “reporting” are all different requirements.
By ISO 17025:2017 requirements, you must consider the impact of measurement uncertainty on results as relates to any conformity statement or interpretation of a result (e.g. pass or fail, if with a tolerance level or out). That is, for each accredited test, you need to do a method risk assessment based on the method performance and measurement uncertainty evaluation. Consider the risk fir example, to the client or the laboratory on a “pass” which would be a “fail” if MU was taken into account.
It is mandatory
to define the rule, communicate the decision and risk to the customer, and have their agreement. i.e. they accept the rule and the risk (Refer to clause 7.1.3)
take risk into account, document and apply the decision rule (Refer to clause 188.8.131.52)
to include the reference to the standard (or regulatory requirement) and the decision rule, clearly associated with each result when there is a conformity requirement (e.g. a quantitative threshold or a condition).
to report which specifications/standards or parts were met based on the rule or parts thereof are met or not met (Refer to clause 184.108.40.206)
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