ISO 15189:2022 · Section 6 · Resource requirements
Clause 6.5: Equipment calibration and metrological traceability
Check the exact requirement in your licensed copy of the standard.
Last reviewed
What this clause is about
Calibration and metrological traceability support confidence that measured values are linked to appropriate references through a documented chain. The practical approach depends on the quantity being measured and the examination system. Not every device needs the same calibration arrangement, and not every medical examination has an available reference system of the same kind.
Identify equipment and measurement functions whose accuracy or uncertainty can affect reported results. Define what is calibrated, the range and conditions, acceptance criteria, interval and required evidence. Calibration establishes a relationship between indications and reference values; adjustment changes the device, while verification checks whether specified requirements are met. Keeping these activities distinct prevents a service label from being mistaken for adequate measurement evidence.
Review calibration certificates and supplier information rather than filing them unread. Check identification, coverage, results, uncertainty where relevant, reference links and whether the service meets the laboratory's needs. For examination systems, understand how calibrators relate to the stated reference and whether changes in lots or procedures affect the chain. Where conventional reference routes are unavailable, document the appropriate alternative basis and its limitations.
Define actions for unacceptable calibration or evidence of drift. Consider equipment adjustment, restricted use, recalibration and review of examinations performed since the last satisfactory status. Internal quality control provides valuable performance monitoring, but it does not by itself establish metrological traceability. Keep records that connect the device or examination system, reference materials, calibration events and acceptance decisions. Review intervals using stability, use, manufacturer information and risk so that calibration remains a purposeful control rather than a calendar exercise.
What assessors typically ask to see
- Which measurement functions require calibration because their accuracy or uncertainty can affect examination results?
- How are calibration ranges, intervals and acceptance criteria justified for the intended laboratory use?
- How are certificates reviewed for identity, measurement coverage, uncertainty and suitability of reference links?
- How is calibrator traceability information obtained and maintained for the examination systems in use?
- What happens when calibration is unacceptable, including assessment of work completed before the problem was recognised?
Documents and records that usually provide evidence
- Calibration and metrological traceability SOP
- Calibration needs and interval assessment register
- Calibration certificates with documented technical review
- Calibrator lot records and traceability information files
- Calibration acceptance and equipment status records
- Out of tolerance investigation and patient impact records
- Reference material receipt and use logs
Ready-made forms mapped to clause 6.5: Calibration Certificate Review Form, Interpolation Calculator.
Common findings to avoid
- Calibration certificates are retained without checking whether their range and uncertainty suit the intended use.
- A maintenance visit or adjustment is recorded as calibration without relevant measurement evidence.
- Internal quality control performance is presented as the only evidence of metrological traceability.
- Unacceptable calibration leads to adjustment but no review of potentially affected previous examination results.
How LabToolkit Pro maps documents to this clause
Each SOP, form and record in LabToolkit Pro can carry clause tags. When a document tagged 6.5 becomes effective, it counts as direct evidence on the readiness dashboard for ISO 15189:2022; links from other standards through the crosswalk are shown separately as indicative coverage. Gaps appear clause by clause, so you can see which parts of 6.5 still need a controlled document or a current record. Readiness is a planning aid — only an accreditation body confirms conformity.
Frequently asked questions
Is calibration the same as adjustment?
No. Calibration describes the relationship between indications and reference values under stated conditions. Adjustment changes the measuring system to improve its response. A device may require calibration before and after adjustment to understand both the previous condition and its suitability for further use. Document the activities separately.
Does good internal quality control prove traceability?
No. Control results help monitor examination performance, but they do not establish the full reference chain behind a reported value. Review calibrator information and relevant reference links separately. Consider both traceability evidence and ongoing performance monitoring when deciding whether an examination system remains suitable.
What if no higher order reference is available?
Identify the reference approach appropriate to the examination and document the basis used, such as an accepted reference procedure or a suitable reference material where available. Explain limitations and avoid claiming an unsupported link. Technical advice may be needed to select a defensible approach and evaluate comparability with other services.
Check the exact requirement in your licensed copy of the standard.
Put it into practice
Draft, approve and e-sign your SOPs with version control, or get the complete template pack.