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| articles:optimizing_calibration_intervals [2025/10/31 15:38] – [Methodologies for the Determination of Calibration Intervals] rrandall | articles:optimizing_calibration_intervals [2025/10/31 16:39] (current) – [Methodologies for the Determination of Calibration Intervals] rrandall |
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| Methodologies for the determination of calibration intervals are defined in documents such as: | Methodologies for the determination of calibration intervals are defined in documents such as: |
| * [[https://ilac.org/publications-and-resources/ilac-guidance-series/|ILAC G24:2022, "Guidelines for the determination of calibration intervals of measuring instruments"]] (free) | * [[https://ilac.org/publications-and-resources/ilac-guidance-series/|ILAC G24:2022, "Guidelines for the determination of calibration intervals of measuring instruments"]] (free) |
| | * [[https://www.oiml.org/en/files/pdf_d/d010-e22.pdf|OIML D 10:2022, "Guidelines for the determination of calibration intervals of measuring instruments"]] (Exactly the same as ILAC G24 – free) |
| * [[https://ncsli.org/store/viewproduct.aspx?id=16959567|NCSLI "RP-1: Establishment and Adjustment of Calibration Intervals"]] ($80) | * [[https://ncsli.org/store/viewproduct.aspx?id=16959567|NCSLI "RP-1: Establishment and Adjustment of Calibration Intervals"]] ($80) |
| There are many methods and theories to calculate calibration intervals, such as those found in NCSL RP-1, Method S1 (Classical Method), Method S2 (Binomial Method), and Method S3 (Renewal time Method). As a result, it can be difficult to choose the best method to determine the interval (Ref. [[https://www.researchgate.net/publication/268400268_A_QUANTITATIVE_COMPARISON_OF_CALIBRATION_INTERVAL_ADJUSTMENT_METHODS|"A Quantitative Comparison of Calibration Interval Adjustment Methods"]]). | There are several methods and theories for calculating calibration intervals, including those outlined in NCSL RP-1, specifically Method S1 (Classical Method), Method S2 (Binomial Method), and Method S3 (Renewal Time Method). As a result, it can be difficult to choose the best method to determine the interval (Ref. [[https://www.researchgate.net/publication/268400268_A_QUANTITATIVE_COMPARISON_OF_CALIBRATION_INTERVAL_ADJUSTMENT_METHODS|"A Quantitative Comparison of Calibration Interval Adjustment Methods"]]). |
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| | <WRAP center round tip 80%> |
| | If the methods in ILAC G24 and/or NCSLI RP-1 seem complicated, just upload the concepts into your favorite AI, along with "A Quantitative Comparison of Calibration Interval Adjustment Methods", and have it perform the calculations for you. |
| | </WRAP> |
| <WRAP center round info 80%> | <WRAP center round info 80%> |
| [[http://www.isgmax.com/|Integrated Sciences Group (ISG)]] offers a free "Method S2" interval calculator (for MS Windows only) augmented by the "Method A3 Interval Tester" (adjusting for "sparse" data) called [[http://www.isgmax.com/calint_freeware.htm|IntervalMAX]]. | [[http://www.isgmax.com/|Integrated Sciences Group (ISG)]] offers a free "Method S2" interval calculator (for MS Windows only) augmented by the "Method A3 Interval Tester" (adjusting for "sparse" data) called [[http://www.isgmax.com/calint_freeware.htm|IntervalMAX]]. |
| Of course, this method assumes that the company is being provided with “as found” data for each calibration performed. \\ | Of course, this method assumes that the company is being provided with “as found” data for each calibration performed. \\ |
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| A critical component when using this methodology is determining the percentage of the maximum permissible error. The higher the percentage, the greater the risk of an instrument being found Out-of-Tolerance (OOT); potentially resulting in nonconforming product escapes. The lower the percentage, the greater the cost associated with lowering the risk of an OOT condition; and reducing the potential for nonconforming product escapes. This percentage will often vary based on the type of instrumentation to which it is applied. \\ | A critical component when using this methodology is determining the percentage of the maximum permissible error. The higher the percentage, the greater the risk of an instrument being found Out-of-Tolerance (OOT), potentially resulting in nonconforming product escapes. The lower the percentage, the greater the cost associated with lowering the risk of an OOT condition and reducing the potential for nonconforming product escapes. This percentage will often vary based on the type of instrumentation to which it is applied. \\ |
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| Most often companies establish a "range" (or "window") for the optimization. For example, IF an instrument is found to exceed 75% of its maximum permissible error, then the calibration interval is shortened. However, IF an instrument is consistently found below 50% of its maximum permissible error, then the calibration interval is lengthened. And IF the instrument is found between 50% and 75% of its maximum permissible error, then the interval is considered acceptable. | Most often, companies establish a "range" (or "window") for the optimization. For example, IF an instrument is found to exceed 75% of its maximum permissible error, then the calibration interval is shortened. However, IF an instrument is consistently found below 50% of its maximum permissible error, then the calibration interval is lengthened. And IF the instrument is found between 50% and 75% of its maximum permissible error, then the interval is considered acceptable. |
| ===== Initial Calibration Intervals ===== | ===== Initial Calibration Intervals ===== |
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