metrology

Metrology is the science of measurement and it encompasses the process of defining internationally accepted units of measurement; the realization of the measurement standards of the units of measurement, and development of measuring instruments and the fields of their application; establishing the traceability chain; as well as all other theoretical and practical aspects referring to measuring, regardless of measuring uncertainty and a field of application. 

Measurements have been inherent in the human societies since the antiquity, because they influence all aspects of human activities. Production management; industry development; environment monitoring (analyzing the quality of water, air and soil); diagnosing and medical treatments; surgery; trade; consumer protection; human health safety assessment; monitoring the fluctuation in air temperature; monitoring climatic change and human health; computer advancement; eclectic energy and telecommunication systems' functioning; recording the sesimicity; astronomy; scientific researches, and alike, are hardly conceivable without measurements.

Metrology can be considered within the framework of three major categories of different levels of complexity and accuracy each:

· Scientific metrology (relates to the establishment and development of measurement standards, as well as to the maintenance of their highest possible levels)

· Industrial metrology (should ensure the adequate functioning of measuring instruments used in industry, as well as in production processes and testing)

· Legal metrology (relates to the accuracy of measurements in the areas where they influence the transparency of economic transactions, and health and safety).

Metrology development is of crucial importance for any state. The persons using the measurements of legal metrology in their everyday activities are not required to be metrology experts, since any state undertakes to be liable for the measurements that influence the transparency of economic transactions and health and safety of humans. Legally controlled measuring instruments should assure the accurate measurements:

· under working conditions, 

· throughout the whole period of use

· within the limits of the given permissible errors

The relevant legislation lay down the requirements that must be met by measuring instruments and the use thereof. To that end, the following shall be followed:

· protective, i.e. preventive measures, and

· repressive measures

Protective measures are approached prior to putting a measuring instrument on the market, i.e. a measuring instrument is put on the market if it has been duly stamped, i.e. if an appropriate Certificate of the Approval of the Type of a Measuring Instrument or Certificate of Verification has been issued therefore.

 Market control is a repressive measure by which each illegal use of measuring instruments is detected. As for the measuring instruments already in use, metrological controls or compulsory re-verifications are prescribed for the purpose of guranteeing the conformity of measuring instruments with the legislative requirements.