The calibration audit prep checklist

Part 1, section 1: Equipment register

• Can you produce a complete list of every instrument that affects product or result quality? Good: one live register, each instrument uniquely identified, nothing tracked on the side in a drawer or a personal spreadsheet.
• Does every register entry match a physical instrument, and every instrument match an entry? Good: the tag on the bench matches the register, serial numbers agree, and a floor walk turns up no unlisted gages.
• Are employee-owned and customer-owned instruments included when they are used to accept product? Good: a personal caliper used at final inspection appears on the register like any other gage.
• Is there a defined way to add, retire, or quarantine an instrument? Good: retired equipment is marked out of service and physically controlled, not just deleted from the list.
• Do indication-only or no-calibration-required instruments carry that status with a justification? Good: a recorded basis for each exemption, not an unlabeled gap an auditor finds first.

Part 1, section 2: Due-date control

• Does every active instrument have a calibration interval and a next-due date? Good: no blank interval fields, and the next-due date follows from the last calibration plus the interval.
• Can you show the basis for the intervals you set? Good: manufacturer guidance, usage, criticality, or the instrument's own in-tolerance history, recorded, not habit.
• Can you list everything due in the next 30, 60, and 90 days? Good: a due list anyone can pull in minutes, not a manual sweep of a spreadsheet.
• Is anything overdue right now, and if so, is it out of use? Good: overdue equipment is identified, removed from service or quarantined, and the decision is recorded.
• Are interval changes recorded with a reason? Good: each lengthening or shortening has a documented basis, such as repeated in-tolerance results or an out-of-tolerance event.

• How to set calibration intervals

Part 1, section 3: Out-of-tolerance handling

• When an instrument comes back out of tolerance, is there a defined response? Good: a documented procedure covering the instrument, the assessment of prior results, and product disposition.
• Can you show a real out-of-tolerance event worked end to end? Good: the event, the impact assessment, the affected measurements or product, and the disposition, all on record.
• Do calibration records capture as-found readings so an impact assessment is even possible? Good: as-found readings before adjustment and as-left readings after, on every event. Without as-found data you cannot judge past results.
• Can you trace what a drifted instrument touched? Good: enough usage records to work back from the instrument to the measurements and product it stood behind since its last good calibration.
• If suspect product may have shipped, who decides on customer notification? Good: a named role and a recorded decision, not an assumption that someone else handled it.

• As-found and as-left readings explained

Part 1, section 4: Records integrity

• Can you produce the complete calibration history for any instrument on request? Good: every calibration, check, and adjustment over the instrument's life, retrievable in minutes.
• Does each record show who performed the work and who approved it? Good: attributable records with names, dates, and signatures or e-signatures.
• Are records protected from silent edits and deletion? Good: changes are controlled and visible. A record cannot be quietly altered after the fact.
• Are retention periods defined and actually met? Good: a stated retention period that satisfies your standard, customers, and regulators, and records that old really exist and are legible.
• Are your calibration certificates complete? Good: instrument identity, date, method, results with units, as-found and as-left readings, uncertainty where required, a traceability statement, and an authorizing signature.

• What a calibration certificate must contain

Part 1, section 5: Traceability chain

• Can you name the specific reference standard behind any given calibration? Good: the record identifies the reference standard by ID, not master gage.
• Are your reference standards themselves in calibration, with certificates on file? Good: each reference standard has a current certificate and its own documented traceability.
• Does the chain reach a national or international measurement standard? Good: a documented, unbroken chain from working instrument to reference standard to an accredited lab or national metrology institute, with uncertainty stated at each link.
• Do you review vendor certificates when they come back, before filing them? Good: a quick check of identity, dates, results and units, uncertainty, traceability, and signature. Problems are chased at receipt, not discovered at audit.
• Where accredited calibration is required, is the work within the lab's accredited scope? Good: the certificate carries the accreditation body's mark and the measurement falls inside the lab's published scope.

• Metrological traceability explained

Part 1, section 6: Training and competence

• Can you show who is authorized to perform calibrations, and on what basis? Good: a competence record for each person, tied to the types of calibration they perform.
• Are training records current for the people doing the work today? Good: records match the current staff list. No calibrations are signed by people with no competence record.
• Do documented procedures exist for in-house calibrations, and do records reference them? Good: a method for each calibration type, and records that cite the method actually used.
• Does a named person own the calibration program? Good: one role responsible for the register, the schedule, and the response when something fails.

Part 2 supplement: ISO 9001, clause 7.1.5

Add the supplement that matches your certification. These build on Part 1, they do not replace it.

• Can you show that monitoring and measuring resources are suitable and maintained (7.1.5.1)? Good: retained records of fitness for purpose for the equipment behind conformity decisions.
• Where traceability is required, is equipment calibrated or verified against traceable standards at defined intervals (7.1.5.2)? Good: every such instrument has a traceable calibration or verification on record, on schedule, or the basis is recorded where no standard exists.
• Is calibration status identifiable on each instrument? Good: anyone at the bench can tell whether an instrument is in calibration, due, or out of service.
• Is equipment safeguarded from adjustments that would invalidate results? Good: seals, access controls, or protected settings, and a record when a safeguard is broken.
• When equipment is found unfit, do you determine whether previous results were affected? Good: a documented determination and the corrective action taken, every time.

• ISO 9001 calibration requirements

Part 2 supplement: ISO/IEC 17025

• Is every equipment item that affects results uniquely identified and labeled with its calibration status (clause 6.4)? Good: labels current, register matching the bench, no ambiguity about the state of any item.
• Are records kept of every calibration, intermediate check, and adjustment (clause 6.4)? Good: intermediate checks are recorded events with results, not undocumented habits.
• Can you demonstrate metrological traceability to the SI through an unbroken chain of calibrations (clause 6.5)? Good: each link documented with its own certificate and its own contribution to measurement uncertainty.
• Do reported results carry measurement uncertainty, and is your decision rule documented (clause 7.8)? Good: uncertainty stated with the result, and wherever you state conformity, the decision rule behind the statement is identified.
• Are technical records attributable, protected from unauthorized change, and sufficient to repeat the work (clause 7.5)? Good: enough recorded detail to reconstruct the calibration, and no way to alter the record without a trace.

• ISO/IEC 17025 calibration software

Part 2 supplement: AS9100, on top of ISO 9001

• Does your equipment register support recall? Good: when an instrument is found out of calibration you can find it, pull it, and evaluate what it touched, quickly.
• Are environmental conditions recorded where they affect the measurement? Good: temperature and humidity captured when they matter, with the requirement defined in the method.
• Will your records survive the retention your contracts require? Good: records legible, retrievable, and backed up for the life of the contract, which in aerospace can mean decades.
• Can you produce the calibration evidence a prime or Nadcap auditor asks for, fast? Good: the complete history for any instrument in one pack, not a week of archaeology.

• AS9100 calibration management

Part 2 supplement: ISO 13485, clause 7.6

• Are documented procedures in place for the control of monitoring and measuring equipment? Good: the procedure exists, is controlled, and matches what people actually do.
• Is equipment calibrated or verified at specified intervals against traceable standards, with the basis recorded where none exists? Good: every interval and traceability basis on record, including the justification for any non-standard reference.
• Is calibration status identified and equipment safeguarded, including during handling and storage? Good: visible status on each item, and protection against adjustment, damage, or deterioration that would invalidate results.
• When equipment is found out of calibration, are validity assessments recorded and affected product acted on? Good: a recorded assessment of prior results, action on the equipment and any affected product, all retained.

• ISO 13485 calibration requirements

Part 2 supplement: IATF 16949, section 7.1.5

• Do you have measurement systems analysis for the gauges in your control plan (7.1.5.1.1)? Good: statistical studies, typically Gage R&R, for each type of inspection and test equipment system named in the control plan, using methods your customer accepts.
• Do calibration records cover every gauge that supports product conformity, including employee-owned and customer-owned equipment (7.1.5.2.1)? Good: no gauge used for acceptance is off the record because of who owns it.
• Do records include as-received (as-found) and after-adjustment (as-left) readings? Good: both readings on the record for every calibration and verification event.
• When a gauge is found out of calibration, is there evidence of risk assessment and customer notification where suspect product may have shipped? Good: the recorded disposition and the notification, with dates.
• Do your external calibration labs meet 7.1.5.3.2? Good: accredited to ISO/IEC 17025 with the calibration in scope, or otherwise customer approved, with the evidence on file.

• IATF 16949 calibration and MSA

After the walkthrough

Count your unchecked boxes and sort them into two piles: record gaps you can close before the audit, and process gaps that need a real fix. Fix the process gaps first. An auditor who finds a tidy record over a broken process will keep digging.

And keep the honest framing. This checklist can show you where you stand. It cannot pass the audit for you, and neither can any tool. Your processes, your evidence, and your assessor decide that.

About this checklist

This checklist is published by Axiospec, a calibration management platform built by CaliTech LLC. It stands on its own. Use it with whatever you run today, paper, spreadsheet, or software.

If the evidence side is where your program struggles, that is the part Axiospec handles: a live equipment register, due-date control, tamper-evident calibration records, and the traceability chain captured on each instrument. The free plan is the full platform for up to 50 active assets with unlimited users and no credit card. Axiospec documents your calibration program. It does not certify compliance, and it never will. That call belongs to your assessor.

• See a working program in the live demo, no signup