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Equipment calibrations are required in accordance with AS9100/AC7004 quality system requirements on production equipment, tools and programs or any other such device that is needed to provide evidence of conformity of a product or service to specified requirements. These specified requirements are usually flowed down by customer specifications or standards that are required to be met in the production of a product or service.

Equipment must be calibrated or validated prior to use, maintained and inspected periodically according to documented procedures.  Whether your equipment is calibrated / validated by an outside source or internally, a register of these monitoring and measuring devices shall be maintained and define the process employed for their calibration including details of equipment type, unique identification, location, frequency of checks, check method, range to be checked, number of points over the range to be checked (3 minimum, unless otherwise stated) and acceptance criteria / accuracy required. These calibration details and any governing specification(s) must also be flowed down to any external calibration source either by including the information directly on a P.O. with the calibration system requirements (e.g. ANSI/NCSL Z540 or ISO 10012) or by referencing a document on the P.O. with these requirements that goes with the P.O. to the calibration source.

Storage requirements, including periodic preservation/condition checks, shall be established for production equipment or tooling in storage.

1. be calibrated or verified at specified intervals, or prior to use, against measurement standards traceable to international or national measurement standards; where no such standards exist, the basis used for calibration or verification shall be recorded;
2. be adjusted or re-adjusted as necessary;
3. be identified to enable the calibration status to be determined;
4. be safeguarded from adjustments that would invalidate the measurement result;
5. be protected from damage and deterioration during handling, maintenance and storage;
6. be recalled to a defined method when requiring calibration.

Calibration Reports

In accordance with ANSI/NCSL Z540, each certificate or report of calibration shall include the following as a minimum:

1. A title, e.g. “Calibration Report” or “Calibration Certificate”
2. Name and address of laboratory, and location where the calibration was carried out if different from the address of the laboratory;
3. Unique identification of the certificate or report (such as serial number) and of each page, and total number of pages;
4. Name and address of customer, where appropriate;
5. Description and unambiguous identification of the item calibrated;
6. Characterization and condition of the calibrated item (This is where the report usually notes the condition as received (e.g. unit received broken or out-of tolerance) and after calibration;
7. Date(s) of performance of calibration, where appropriate;
8. Identification of the calibration procedure used, or unambiguous description of any non-standard method used (This should also include identifying the calibration system specification(s) used);
9. Reference to sampling procedure, where relevant;
10. Any deviation from, additions to or exclusions from the calibration methods, and any other information relevant to a specific calibration, such as environmental conditions;
11. Measurements, examinations and derived results, supported by tables, graphs, sketches and photographs, as appropriate, and any failures identified.  (Note: You should also cover in your P.O. requirements to notify you immediately, if a calibrated item is received broken or out-of-tolerance so an investigation can be initiated to determine if there is product impact. The calibration source, under ANSI/NCSL Z540, is required to notify you, but may not be aware of it.)
12. A statement of the estimated uncertainty of the calibration results (where relevant)
13. A signature and title, or an equivalent identification of the person(s) accepting responsibility for the content of the certificate or report (however produced), and date of the issue;
14. Where relevant, a statement to the effect that the results relate only to the items calibrated;
15. A statement that the certification or report shall not be reproduced except in full, without the written approval of the laboratory;
16. Special limitations of use; and
17. Traceability statement
18. ISO 10012 also requires the calibration / verification frequency and the accuracy requirements be noted on a report.