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সর্ব-শেষ হাল-নাগাদ: ১০ অক্টোবর ২০২১







A set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring system, or values represented by a material measure or a reference material, and the corresponding values realized by standards


Fulfillment by a product, process, or service of specified requirements

Conformity assessment

An activity concerned with determining directly or indirectly that relevant requirements are fulfilled

International standard

Standard recognized by an international agreement to serve internationally as the basis for assigning values to other standards of the quantity concerned

International System of Units (SI)

The units of the metric system used universally in science

Legal metrology

Legal metrology comprises all measurements carried out for any legal purpose and includes measurements that are subject to regulation by law or government decree


A set of operations having the object of determining a value of a quantity

Metre Convention

The Metre Convention is an international treaty that provides the basis of all international agreements on units of measurement


The science of measurement

National standard

Standard recognized by a national decision to serve, in a country, as the basis for assigning values to other standards of the quantity concerned

Pattern approval

Examination of the pattern (design) of a measuring instrument against national or international specifications

Primary standard

A 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

Reference material

A material or substance one or more of whose property values are sufficiently homogeneous and well established to be used for the calibration of an apparatus, the assessment of a measurement method, or for assigning values to materials

Reference standard

A standard generally having the highest metrological quality available at a given location or in a given organization from which measurements made there are derived

Secondary standard

A standard whose value is assigned by comparison with a primary standard of the same quantity


Traceability is the 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

Verification by sampling

Verification of a homogeneous batch of measuring instruments based on the results of examination of a statistically appropriate number of specimens selected at random from an identified lot​

Verification of a measuring instrument

Procedure (other than pattern approval) which includes the examination and marking and/or issuing of a verification certificate, that ascertains and confirms that the measuring instrument complies with the statutory requirements

Working standard

A standard that is used routinely to calibrate or check material measures, measuring instruments, or reference materials


Authorization, approval, or recognition of meeting a standard