4.11. Control of Inspection, Measuring, and Test Equipment

4.11.1. General

You must ensure that proper maintenance, review, and control of all of your test, calibration, and any other test equipment (including jigs, fixtures, templates, patterns, and software) as defined by your quality plan. This equipment must be capable of measuring to the level of accuracy specified in the test requirements. Your employees must have been trained in the use and proper applications of the equipment. If your customers request the technical test data on your inspection equipment to conduct their own study to determine functional adequacy, they must be made available to them.

Compliance with this section requires that:

You have a documented system that ensures the identification and correct calibration of all equipment used to perform testing and inspection of materials and products.
When using test software to verify product fitness, they shall be regularly rechecked to ensure correctness.
Records of calibration, verification, and accuracy shall be maintained and available for customer inspection.

4.11.2. Control procedure

To comply with this section, you should address the following points:

A review of the inspections and tests to be performed shall be identified and completed.
Identification and acquisition of appropriate test and measurement equipment capable of satisfying the requirements shall be completed.

Identify what measure is to be made, by what piece of equipment, and to what specific tolerances.

You must identify and calibrate all your inspection and test equipment at defined and valid intervals to a national or international standard. When there is no such standard available, you must create your own standard.

Identify and calibrate all test equipment at regular intervals of time or usage. The equipment must be capable of making the required measurements. The calibration of this equipment must be compared with a known “good” with a clear path to a nationally recognised standard. Calibration cycle times are usually based on the manufacturer’s guidelines, or less often by history and usage. If there are no standards to reference, you must document how to meet your desired standard.

You must define how and when you will calibrate your equipment.
You must define a reasonable course of action when you discover the equipment is out of calibration.

Have a calibration system to identify the equipment to be used, where it is used, the method of confirmation, the frequency of inspection, and the procedure for when it is out of conformance.

There must be some form of identification on the calibrated equipment that would indicate its current status.

Place some type of identification mark on the equipment to show its current calibration status.

You must maintain calibration records for each piece of equipment under calibration control.

Maintain records on the calibration with at least one prior record available.

You must review the calibration records when the equipment is found to be out of calibration. From this review you will need to define a corrective action to minimise future nonconformances.

Document the occurrence and return to the prior calibration for review should you find a device out of calibration. When a nonconformance trend is indicated, correct the nonconformance by shortening the calibration cycle or replacing a tool. Notification should also be sent to the usage point of the calibration equipment for reverification with a corrected tool.

Ensure that the working environment is conducive to effective testing.

Properly store and maintain (through employee training) the calibration equipment.

Ensure that the equipment is adequately protected and handled between calibration checks. This would include making sure there is no unauthorised adjustments to the equipment.

Permit only authorised personnel to make adjustments to the equipment or software.

Not all your measurement or calibration equipment is required to satisfy the previous requirements, only those used in the final product test inspections or as defined in your quality plan. If in-process inspections are used to validate requirements within the process, and they support your final inspection and testing activity, then they must be made part of your calibration control scheme. Should you determine that a particular instrument is not required to meet the ISO 9000 criteria, then you may except it by identifying it as such. However, keeping as many pieces of equipment as possible in compliance with these requirements will help you to produce the best product at the lowest cost and achieve the goal of zero defects. Third-party certification agents take a dim view if you try to stipulate that only your final test equipment needs calibration control. They will usually cite a failure in your corrective action process if you attempt to use this loophole. We advice that you discuss this with your auditor beforehand.