Compliance · 6 min read
ISO 13485 Calibration Requirements for Medical Device Manufacturers
For a medical device manufacturer, calibration isn’t a maintenance chore — it’s part of the objective evidence that your device meets its specifications. Here’s what ISO 13485:2016 requires, and how notified-body auditors test it.
Clause 7.6: control of monitoring and measuring equipment
ISO 13485:2016 clause 7.6 requires you to determine what monitoring and measurement you need, and to control the equipment that performs it under documented procedures — a stricter posture than ISO 9001, which no longer mandates documented procedures the same way. Equipment must be calibrated or verified at specified intervals (or before use) against measurement standards traceable to international or national standards; where no such standard exists, the basis must be recorded.
The clause continues: equipment must be adjusted as necessary, identified so its calibration status can be determined, safeguarded from adjustments that would invalidate results, and protected from damage during handling and storage. Records of calibration results must be maintained — and under clause 4.2.5, retrievable for your retention period.
Out-of-tolerance: where audits get uncomfortable
When equipment is found nonconforming, clause 7.6 requires you to assess the validity of previous measuring results and take appropriate action on the equipment and any product affected. In practice, a notified-body auditor will pick an out-of-tolerance event from your records and walk the trail: was the impact assessed? Was affected product evaluated? Is there a record?
That trail is only walkable if your calibration certificates contain as-found data. A certificate that says “calibrated” without readings leaves you unable to determine how far out the instrument was — and therefore unable to complete the assessment the standard requires. Every American Gage certificate reports as-found/as-left data with measurement uncertainty and NIST traceability, under A2LA ISO/IEC 17025 accreditation.
FDA alignment
US manufacturers typically satisfy FDA expectations in the same program: FDA’s device requirements (21 CFR 820, moving to alignment with ISO 13485 under the Quality Management System Regulation) similarly demand calibrated equipment, traceable standards, documented procedures, and remedial action when equipment is out of specification. One well-designed calibration program serves both masters — and your supplier’s accredited certificates are the backbone of it.
Common questions
Does ISO 13485 require calibration before every use?
No — it requires calibration or verification at specified intervals, or prior to use, as you define in your procedures. Most manufacturers use scheduled intervals with interim checks for critical equipment.
What records does ISO 13485 require for calibration?
Records of calibration and verification results must be maintained (clauses 7.6 and 4.2.5) — in practice: certificates with data, the standards used and their traceability, environmental conditions where relevant, and evidence of your out-of-tolerance assessments.
Do notified bodies expect ISO 17025-accredited calibration suppliers?
Accreditation is the accepted evidence that your calibration supplier is competent and its results traceable — and supplier controls under ISO 13485 clause 7.4 make you responsible for that competence. An accredited lab’s scope and certificate number make the qualification file straightforward.