Instruments that cannot be calibrated are usually discarded if they are found to be out of tolerance.
4.1.5 Documentation
4.1 Introduction Quantity determination is one of the main functions of NR OGC services, and this is typically achieved by manually measuring the product. It is critical; therefore, that all inspection and measurement equipment used i.e. tapes, bobs, rulers, thermometers, etc., are free of any deficiencies that could cause erroneous results. We achieve this by calibrating or verifying the accuracy of this equipment against ‘master’ equipment that has known precision and is traceable to a national or international standard. The elements of calibration or accuracy verification are detailed in this section.
Calibration and verification of all inspection and measurement equipment is documented by the use of Calibration Records. At a minimum, this documentation shall show: • The identification mark or serial number of the equipment
4.1.2 Records
Each SGS facility is required to have a listing of all measurement equipment that requires calibration or verification. This calibration or verification may be conducted in-house, by the equipment manufacturer, or by a suitable contract calibration service.
• Date of calibration
• By whom calibrated
• When the next calibration is due
4.1.3 Interval or Schedule
This document will also identify the master reference standard used and its traceability to the appropriate standard. Upon receipt of measuring or testing equipment, calibrated by the equipment manufacturer or a suitable contract calibration service, the designated supervisory staff must ensure that the accompanying Calibration Certificate specifies the correct calibration standard, including the validity of the calibration and expiration. 4.2 Equipment Requirements Before any use of measurement equipment, the operator should verify that the instrument is in calibrated condition, either by running standards and/or controls or by confirming that the expiry dates have not been exceeded.
The interval between calibrations is established by the appropriate measurement standard. Intervals may be shortened to assure continued accuracy as evidenced by the results of previous calibration, or to meet client, regulatory and/or industry requirements.
4.1.1 Calibration vs. Verification
4.1.4 Traceability
We tend to use the term ‘calibration’ to cover both verification and calibration. Technically, calibration only applies to instruments such as portable electronic thermometers whose readouts can be adjusted. Instruments that cannot be adjusted, such as tapes, bobs and liquid-in-glass thermometers have their accuracy verified. Instruments capable of being calibrated that are found to be out of tolerance are adjusted or repaired to bring them back into tolerance.
Calibration equipment must be certified as being traceable, directly or indirectly, to a national or international standard.
Calibration is performed only in a suitable environment.
Measuring equipment and reference standards are handled, preserved, and stored so that their accuracy and fitness for use is maintained throughout the calibration intervals.
30
Made with FlippingBook Annual report maker