FDA 483 Citations for Calibration Under 21 CFR 820.72

23 hours ago

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"Procedures to ensure equipment is routinely [calibrated] [inspected] [checked] [maintained] have not been [adequately] established." FDA investigators cited 21 CFR 820.72(a) with that wording 30 times on system-generated Form FDA 483s in fiscal year 2025.

Every acceptance decision depends on a measurement. If gauges, scales, testers and sensors are not calibrated, or if out-of-tolerance results are ignored, the manufacturer cannot show that accepted product actually met its specifications.

What the citation means

Examples written after "Specifically" usually describe:

Inspection or test equipment used for acceptance with no calibration record
Calibration overdue, with the equipment still in use
No calibration status label or equivalent identification
Calibration certificates from contractors with no traceability statement or no as-found data
Out-of-tolerance results with no assessment of product measured since the last good calibration
No defined accuracy or tolerance requirements for the equipment
Personal or uncontrolled measuring tools used for acceptance
Software in test equipment not validated

What 21 CFR 820.72 required

Under the Quality System Regulation, each manufacturer had to ensure that all inspection, measuring and test equipment, including mechanical, automated or electronic equipment, is suitable for its intended purposes and capable of producing valid results. Procedures had to ensure that equipment is routinely calibrated, inspected, checked and maintained, and had to include provisions for handling, preservation and storage.

Under 820.72(b), calibration procedures had to include specific directions and limits for accuracy and precision. When accuracy and precision limits were not met, there had to be provisions for remedial action to reestablish the limits and to evaluate whether there was any adverse effect on the device's quality. Calibration standards had to be traceable to national or international standards, or an independent reproducible standard where that was not practical. Records had to include the equipment identification, calibration dates, the individual performing each calibration and the next calibration date, and these had to be displayed on or near each piece of equipment or readily available.

What changed under QMSR

Under QMSR, in effect since February 2, 2026, requirements come from ISO 13485:2016 clause 7.6, Control of monitoring and measuring equipment. The organization must document procedures to ensure monitoring and measurement can be carried out consistently with requirements. Where necessary to ensure valid results, measuring equipment must:

Be calibrated or verified, or both, at specified intervals or prior to use, against measurement standards traceable to international or national standards, with the basis recorded where no such standards exist
Be adjusted or re-adjusted as necessary, with the adjustments recorded
Have identification to determine its calibration status
Be safeguarded from adjustments that would invalidate the measurement result
Be protected from damage and deterioration during handling, maintenance and storage

When equipment is found not to conform, the organization must assess and record the validity of previous measuring results and take appropriate action on the equipment and any product affected. Software used for monitoring and measurement must be validated before initial use and after changes, with an approach proportionate to risk.

How to respond to the 483

FDA generally considers responses received within 15 business days of the close of the inspection before deciding on further action.

Calibrate and assess

Calibrate the equipment cited, or remove it from service. For any equipment found out of tolerance, identify product measured since the last good calibration, assess whether the error could have affected acceptance decisions and record the conclusion.

Inventory all measuring equipment

List every instrument used for acceptance, process monitoring or environmental monitoring, including test fixtures and software-driven testers. Define accuracy requirements, calibration methods and intervals for each.

Fix the system

A calibration procedure covering intervals, methods, standards, traceability, labeling, records, out-of-tolerance handling and contractor calibration
A calibration database with recall dates
Out-of-tolerance investigation with product impact assessment
Control of personal tools: banned for acceptance, or brought into the system
Review of contractor certificates for as-found data, traceability and accreditation
Validation of measurement software

Verify

Audit calibration status in the field and review overdue items monthly.

What a compliant calibration procedure contains

Scope and equipment identification
Accuracy requirements and test uncertainty considerations
Calibration intervals and how they are changed
Methods, standards and traceability
Status identification
Handling, storage and protection
Out-of-tolerance investigations and product impact
Contracted calibration services
Records
Validation of measurement software

Common mistakes in calibration responses

Calibrating the instrument but skipping the product impact assessment
Accepting contractor certificates without as-found data
Ignoring fixtures, go/no-go gauges and software-based testers
Lengthening intervals without data
Allowing overdue equipment to stay in use without a decision

Example: how one response section might read

This illustrates structure only; your response must describe your own facts.

Observation 13: Procedures to ensure equipment is routinely calibrated have not been adequately established. Specifically, the leak tester used for final acceptance was found 8 percent out of tolerance with no evaluation of product.

Response:

Product assessment: The as-found error was applied to leak test results for 41 lots tested since the prior calibration. All results remained within specification after correction, and no product action was needed.
Root cause: The calibration procedure did not require an impact assessment for out-of-tolerance results, and contractor certificates were filed without review.
Corrective action: The procedure now requires quality review of every certificate and a documented impact assessment for any out-of-tolerance result.
Extended review: All 186 instruments were reconciled against the calibration database. Eleven unlisted instruments were added and calibrated by a stated date.
Verification: Quality will report overdue calibrations and out-of-tolerance results at each management review.

Frequently asked questions

Does every tool need calibration?

Equipment used to make or verify quality decisions needs calibration or verification. Tools used only for reference can be labeled "for reference only," as long as they are never used for acceptance.

Do contract calibration labs need ISO/IEC 17025 accreditation?

Neither ISO 13485 nor QMSR requires it by name, but accreditation is the easiest way to show traceability and competence. Without it, evaluate the lab as a supplier.

What happens when equipment fails calibration?

Assess and record the validity of previous results, decide whether affected product is acceptable and take action on the equipment and product.

How A.P. Lyon documents help

A.P. Lyon's Calibration System Procedure for ISO 13485 and FDA QMSR covers intervals, traceability, status labeling, out-of-tolerance investigations and records. Companies with ISO 9001 can use the Dual-Standard Measurement and Metrological Confirmation Procedure. The Software Validation Procedure covers measurement software.

Documents are editable Word and Excel files and must be adapted to your equipment and organization. Accuracy limits must come from your own product requirements.

Next steps

Calibrate the cited equipment and assess affected product
Bring every measuring instrument into the calibration system
Require impact assessments for out-of-tolerance results
Respond within 15 business days with dates for each action

To build a complete set of procedures at a volume discount, use Build Your QMS. For help with a 483 response, see A.P. Lyon consulting services.

Not sure where your quality system stands? Take the free QMS gap check: about 20 questions, an instant report of your gaps by clause, and the procedures that close each one.