Quality
How to read a Certificate of Analysis
A framework for checking sample identity, scope, methods and results in an analytical report.
A useful CoA clearly connects the document to the material tested. Check the name, unique identifier, dates, laboratory and approval status.…
02Method, specification and resultEach test should state what was measured, by which procedure and against what criterion. A result without a unit or clear…
03What a CoA does not proveA CoA summarises defined tests on a particular sample. It does not establish every possible attribute or replace evaluation of the…
Document and sample identification
A useful CoA clearly connects the document to the material tested. Check the name, unique identifier, dates, laboratory and approval status. If these do not allow reliable matching, even a detailed result has limited traceability.
Method, specification and result
Each test should state what was measured, by which procedure and against what criterion. A result without a unit or clear calculation basis can be misread. The word “passes” is meaningful only when the corresponding specification is visible and suitable.
What a CoA does not prove
A CoA summarises defined tests on a particular sample. It does not establish every possible attribute or replace evaluation of the method and laboratory. Confidence is strengthened when primary data or a report is available on request.
LABORATORY APPLICATION
Turning the principle into an auditable record
Use a four-column review: what the document claims, which method supports it, what result was reported and what uncertainty remains. Request a supporting report or primary data when the summary cannot support a decision. Missing information should not be converted into a positive conclusion.
PRIMARY & OFFICIAL SOURCES
Sources and further reading
COMMON QUESTIONS
Questions specific to this topic
What should be checked first on a CoA?
Clear matching between document and material, together with laboratory, dates and approval status.
What does ‘passes’ mean?
That the reported result meets a defined specification; without a visible criterion the statement is incomplete.
Is a CoA sufficient on its own?
It depends on the decision and scope. Critical assessments may require method details, primary data or additional tests.