What is Metrology?
Metrology
Metrology is defined as the science and process of ensuring that measurement meets specified degrees of both accuracy and precision.
Importance of Metrology
The importance of the metrology system is intuitively felt in all human activity. These systems are needed not only to comply with standard and regulation requirements for a unified international system, but also to facilitate world trade and eliminate technical trade barriers. That is why functioning metrology and quality infrastructure systems are preconditions for developing countries to be able to cope with international demands. They are also a precondition to be able to satisfy the demands of consumers who are more and more aware of and interested in issues of quality, productions methods, and their implications on the environment and on workers.
Several studies have shown that what is spent on measurement equates 4% to 6% of the national income in industrial countries. This represents several hundred million of the European market alone, and if we took 3% for the Arabian region, this ratio equates to several tenths of millions. This is more than what the Arabian country’s budget can withstand.
Metrology provides an infrastructure not only for physical and natural sciences but exceeds to comprise environment, medicine, agriculture, and food. Various high-level studies demonstrate the impact of measurement on society.
Traceability
In order for JNMI to achieve traceability, it must adjoin one of the national groups that have a direct bond to the BIPM committee. That is why our national center joined the Asia-pacific metrology group (APMP).
SI units
The International System of Units (SI) is the modern form of the metric system. It comprises a coherent system of units of measurement starting with seven base units:
- Length measured in metre (meter): m
- Mass measured in kilogram: kg
- Time measured in second: s
- Electric current measured in ampere: A
- Thermodynamic temperature measured in kelvin: K
- Amount of substance measured in mole: mol
- Luminous intensity measured in candela: cd
The establishment of this system came as a definite result of the need to have better productivity and a unified measuring system for all sectors in modern society.
Metrology Terminology
Calibration
A set of operations that establish under specified conditions the relationship between values of quantities indicated by instrument or measuring system, or values represented by a material measure or reference material and the corresponding value realized by standards.
International Standard
Document: a document outlining and/or defining requirements and/or conditions, recognized by international agreement to serve as a common basis for evaluation of affected systems, protocols, and/or methods (e.g. ISO 17025). Measurement: standard recognized by international agreement to serve internationally as the basis for assigning values to other standards of the quantity concerned (e.g. Meter).
Reference Standard
Measurement standards generally having the highest metrological quality available at a given location or in a given organization, from which measurements made there are derived.
Standard, primary
Standard that is designated or widely acknowledged as having the highest metrological qualities and whose value is accepted without reference to other standards of the same quantity.
Standard, secondary
Standard whose value is assigned by comparison with a primary standard of the same quantity.
Standard, working
Standard that is used routinely to calibrate or check material measures, measuring instruments, or reference materials.
Traceability
Property of the result of a measurement or the value of a standard, whereby it can be related to stated references, usually national or international standards, through an unbroken chain of comparisons all having stated uncertainties.
True value of Quantity
Quantity value is consistent with the definition of quantity.
Accuracy of Measurement
The closeness of agreement between a quantity value obtained by measurement and the true value of the measurand.