Laboratory activity - where to draw the line

You asked why a testing laboratory, who conforms to ISO 17025 requirements to verify and calibrate their own equipment, cannot offer calibration services and calibration certificates for clients.

Although ISO 17025 is applicable to both testing and calibration laboratories, the application of the standard differs. From a laboratory point of view, there are specific laboratory activities for calibration and testing laboratories, involving different technical and performance capability of equipment, operational activities and risks. Reporting requirements are also different. For the required purpose of metrological traceability to international units, an unbroken chain of calibrations is required, linked to appropriate references. For each chain a measurement uncertainty must be calculated so that the overall uncertainty can be known. Only then can a testing lab determine if a method is adequate for use. Testing laboratories generally rely on competent calibration laboratories to meet these specific metrological needs.

From an accreditation point of view, accreditation bodies are themselves accredited for specific scopes, where testing and calibration scopes are independent and programs are managed separately. This said, an organisation could, in principle, apply separately for accreditation as a Calibration laboratory and as a Testing laboratory, each with their different range of activities and scope of accreditation

Have a look at another ISO 17025 answered question that all addressed this topic - Calibration of measurement equipment, available at https://community.advisera.com/topic/calibration-of-measurement-equipment//