Definitions

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1. Calibration - A set of operations which established, under specified conditions, the relationship between values indicated by a measuring instrument or measuring system, or values represented by a material measure, and the corresponding known values of a measurand. *  

2. Interlaboratory comparisons - Organization, performance and evaluation of calibrations  on the same or similar items by two or more laboratories in accordance with predetermined conditions. **  

3. International (measurement) standard - A standard recognized by an international agreement to serve internationally as the basis for fixing the value of all other standards of the quantity concerned. **  

4. Laboratory/calibration laboratory - Body that calibrates or performs calibrations and verifications. **  

5. Limits of permissible error (of a measuring instrument) - The extreme values of an error permitted by specifications, regulations, etc. for a given measuring instrument. **  

6. Measurand - A quantity subjected to measurement. **  

7. Measurement - A set of operations having the object of determining the value of a measurand. **  

8. Measurement standard - A material measure, measuring instrument, reference material or system intended to define, realize, conserve or reproduce a unit or on or more known values of a quantity to serve as a reference. **  

9. Measuring and test equipment - All of the measuring instruments, measurement standards, reference materials, and auxiliary apparatus that are necessary to perform a measurement.  This term includes measuring equipment used in the course of testing and inspection, as well as that used in calibration. **  

10. Proficiency testing - Determination of the laboratory calibration performance by interlaboratory comparisons or other means. **  

11. Quality manual - A document stating the quality policy, quality system and quality practices of an organization. **  

12. Test - A technical operation that consists of the determination of one or more characteristics of performance of a given product, material, equipment, organism, physical phenomenon, process or service, according to a specified procedure. *  

13. Traceability - The property of a result of a measurement whereby it can be related to appropriate standards, generally national or international standards, through an unbroken chain of comparisons. **  

14. Uncertainty of measurement - parameter, associated with the result of a measurement, that characterizes the dispersion of the values that could reasonably be attributed to the measurand. **  

* ISO/IEC Guide 25:1990 (E) ** NCSL Handbook for Z540-1-1994