What is metrology and why does humanity need it? Metrology - what is it? Basic concepts of metrology M in metrology

- (Greek, from metron measure, and logos word). Description of weights and measures. Dictionary foreign words, included in the Russian language. Chudinov A.N., 1910. METROLOGY Greek, from metron, measure, and logos, treatise. Description of weights and measures. Explanation of 25,000 foreign... ... Dictionary of foreign words of the Russian language

Metrology- The science of measurements, methods and means of ensuring their unity and ways to achieve the required accuracy. Legal metrology A section of metrology that includes interrelated legislative and scientific and technical issues that require... ... Dictionary-reference book of terms of normative and technical documentation

- (from the Greek metron measure and...logy) the science of measurements, methods of achieving their unity and the required accuracy. The main problems of metrology include: the creation of a general theory of measurements; formation of units of physical quantities and systems of units;… …

- (from the Greek metron measure and logos word, doctrine), the science of measurements and methods of achieving their universal unity and the required accuracy. To the main M.'s problems include: the general theory of measurements, the formation of physical units. quantities and their systems, methods and... ... Physical encyclopedia

Metrology- the science of measurements, methods and means of ensuring their unity and ways of achieving the required accuracy... Source: RECOMMENDATIONS FOR INTERSTATE STANDARDIZATION. STATE SYSTEM FOR ENSURING UNITY OF MEASUREMENT. METROLOGY. BASIC… Official terminology

metrology- and, f. metrologie f. metron measure + logos concept, doctrine. The doctrine of measures; description of various weights and measures and methods for determining their samples. SIS 1954. Some Pauker was awarded a full award for a manuscript on German about metrology,... ... Historical Dictionary of Gallicisms of the Russian Language

metrology- The science of measurements, methods and means of ensuring their unity and ways to achieve the required accuracy [RMG 29 99] [MI 2365 96] Topics metrology, basic concepts EN metrology DE MesswesenMetrologie FR métrologie ... Technical Translator's Guide

METROLOGY, the science of measurements, methods of achieving their unity and the required accuracy. The birth of metrology can be considered the establishment at the end of the 18th century. standard for the length of a meter and the adoption of the metric system of measures. In 1875 the International Metric Code was signed... Modern encyclopedia

A historical auxiliary historical discipline that studies the development of systems of measures, monetary accounts and taxation units among various nations... Big Encyclopedic Dictionary

METROLOGY, metrology, many. no, female (from the Greek metron measure and logos doctrine). The science of weights and measures of different times and peoples. Dictionary Ushakova. D.N. Ushakov. 1935 1940 ... Ushakov's Explanatory Dictionary

Books

Metrology
Metrology, Bavykin Oleg Borisovich, Vyacheslavova Olga Fedorovna, Gribanov Dmitry Dmitrievich. The main provisions of theoretical, applied and legal metrology are outlined. Considered theoretical basis and applied issues of metrology at modern stage, historical aspects...

Basic metrology terms are established by state standards.

1. Basic concept of metrology - measurement. According to GOST 16263-70, measurement is finding a value physical quantity(FV) experimentally using special technical means.

The result of a measurement is the receipt of a value during the measurement process.

With the help of measurements, information is obtained about the state of production, economic and social processes. For example, measurements are the main source of information about the compliance of products and services with the requirements of regulatory documentation during certification.

2. Measuring instrument(SI) - special technical means, storing a unit of a quantity, to compare the measured quantity with its unit.

3. Measure is a measuring instrument designed to reproduce a physical quantity of a given size: weights, gauge blocks.

To assess the quality of measurements, the following measurement properties are used: accuracy, convergence, reproducibility and accuracy.

- Correctness- the property of measurements when their results are not distorted by systematic errors.

- Convergence- a property of measurements that reflects the closeness to each other of measurement results performed under the same conditions, by the same measuring instruments, by the same operator.

- Reproducibility- a property of measurements that reflects the closeness to each other of the results of measurements of the same quantity, performed under different conditions - at different times, in different places, with different methods and measuring instruments.

For example, the same resistance can be measured directly with an ohmmeter, or with an ammeter and a voltmeter using Ohm's law. But, naturally, in both cases the results should be the same.

- Accuracy- a property of measurements that reflects the proximity of their results to the true value of the measured value.

This is the main property of measurements, because most widely used in the practice of intentions.

The accuracy of SI measurements is determined by their error. High measurement accuracy corresponds to small errors.

4. Error is the difference between the SI readings (measurement result) Xmeas and the true (actual) value of the measured physical quantity Xd.

The task of metrology is to ensure the uniformity of measurements. Therefore, to generalize all the above terms, use the concept uniformity of measurements- a state of measurements in which their results are expressed in legal units, and errors are known with a given probability and do not go beyond established limits.

Measures to actually ensure the uniformity of measurements in most countries of the world are established by law and are part of the functions of legal metrology. In 1993, the Russian Federation Law “On Ensuring the Uniformity of Measurements” was adopted.

Earlier legal norms were established by government regulations.

Compared to the provisions of these resolutions, the Law established the following innovations:

In terminology - outdated concepts and terms have been replaced;

In licensing metrological activities in the country, the right to issue a license is granted exclusively to the bodies of the State Metrological Service;

A unified verification of measuring instruments has been introduced;

A clear separation of the functions of state metrological control and state metrological supervision has been established.

An innovation is also the expansion of the scope of state metrological supervision to banking, postal, tax, customs operations, as well as to mandatory certification of products and services;

Calibration rules have been revised;

Voluntary certification of measuring instruments has been introduced, etc.

Prerequisites for the adoption of the law:

The country's transition to a market economy;

As a result, the reorganization of state metrological services;

This led to a violation centralized system management of metrological activities and departmental services;

Problems arose during state metrological supervision and control due to the emergence of various forms property;

Thus, the problem of revising the legal, organizational, and economic foundations of metrology has become very urgent.

The objectives of the Law are as follows:

Protecting citizens and the economy Russian Federation from the negative consequences of unreliable measurement results;

Promoting progress based on the use of state standards of units of quantities and the use of measurement results of guaranteed accuracy;

Creating favorable conditions for the development of international relations;

Regulation of relations between government bodies of the Russian Federation and legal and individuals on issues of manufacturing, production, operation, repair, sale and import of measuring instruments.

Consequently, the main areas of application of the Law are trade, healthcare, environmental protection, and foreign economic activity.

The task of ensuring the uniformity of measurements is assigned to the State Metrological Service. The law determines the intersectoral and subordinate nature of its activities.

The intersectoral nature of the activity means legal status State Metrological Service, similar to other control and supervisory government bodies (Gosatomnadzor, Gosenergonadzor, etc.).

The subordinate nature of its activities means vertical subordination to one department - Gosstandart of Russia, within the framework of which it exists separately and autonomously.

In pursuance of the adopted Law, the Government of the Russian Federation in 1994 approved a number of documents:

- “Regulations on state scientific and metrological centers”,

- “The procedure for approving regulations on metrological services of federal executive authorities and legal entities»,

- “The procedure for accreditation of metrological services of legal entities for the right to verify measuring instruments”,

These documents, together with the specified Law, are the main legal acts on metrology in Russia.

Metrology

Metrology(from Greek μέτρον - measure, + other Greek λόγος - thought, reason) - The subject of metrology is the extraction of quantitative information about the properties of objects with a given accuracy and reliability; the regulatory framework for this is metrological standards.

Metrology consists of three main sections:

Theoretical or fundamental - considers general theoretical problems (development of the theory and problems of measuring physical quantities, their units, measurement methods).
Applied- studies issues of practical application of developments in theoretical metrology. She is in charge of all issues of metrological support.
Legislative- establishes mandatory technical and legal requirements for the use of units of physical quantities, methods and measuring instruments.

Metrologist

Goals and objectives of metrology

creation of a general theory of measurements;
formation of units of physical quantities and systems of units;
development and standardization of methods and measuring instruments, methods for determining measurement accuracy, the basis for ensuring the uniformity of measurements and uniformity of measuring instruments (the so-called “legal metrology”);
creation of standards and exemplary measuring instruments, verification of measures and measuring instruments. The priority subtask of this direction is to develop a system of standards based on physical constants.

Metrology also studies the development of a system of measures, monetary units and counting in a historical perspective.

Axioms of metrology

Any measurement is a comparison.
Any measurement without a priori information is impossible.
The result of any measurement without rounding the value is a random variable.

Metrology terms and definitions

Unity of measurements- a state of measurements, characterized by the fact that their results are expressed in legal units, the sizes of which, within established limits, are equal to the sizes of units reproduced by primary standards, and the errors of the measurement results are known and with a given probability do not go beyond the established limits.
Physical quantity- one of the properties of a physical object, common in qualitative terms for many physical objects, but in quantitative terms individual for each of them.
Measurement- a set of operations for the use of a technical means that stores a unit of physical quantity, ensuring the determination of the relationship of the measured quantity with its unit and obtaining the value of this quantity.
Measuring instrument- a technical device intended for measurements and having standardized metrological characteristics reproducing and (or) storing a unit of quantity, the size of which is assumed to be unchanged within the established error over a known time interval.
Verification- a set of operations performed to confirm the compliance of measuring instruments with metrological requirements.
Measurement error- deviation of the measurement result from the true value of the measured value.
Measuring instrument error- the difference between the reading of the measuring instrument and the actual value of the measured physical quantity.
Measuring instrument accuracy- characteristic of the quality of a measuring instrument, reflecting the proximity of its error to zero.
License- this is a permit issued by the state metrological service authorities on the territory assigned to it to an individual or legal entity to carry out activities for the production and repair of measuring instruments.
Standard unit of quantity- a technical means intended for transmission, storage and reproduction of a unit of value.

History of metrology

Metrology dates back to ancient times and is even mentioned in the Bible. Early forms Metrology involved the establishment by local authorities of simple arbitrary standards, often based on simple practical measurements, such as arm length. The earliest standards were introduced for quantities such as length, weight and time, this was done to simplify commercial transactions as well as recording human activities.

Metrology acquired a new meaning during the era of the industrial revolution; it became absolutely necessary to ensure mass production.

Historically important stages in the development of metrology:

XVIII century - establishment of the meter standard (the standard is kept in France, in the Museum of Weights and Measures; currently it is more of a historical exhibit than a scientific instrument);
1832 - creation of absolute systems of units by Carl Gauss;
1875 - signing of the international Meter Convention;
1960 - development and establishment of the International System of Units (SI);
20th century - metrological studies of individual countries are coordinated by International Metrological Organizations.

Milestones in the national history of metrology:

accession to the Meter Convention;
1893 - creation by D. I. Mendeleev of the Main Chamber of Weights and Measures ( modern name: “Research Institute of Metrology named after. Mendeleev");

World Metrology Day is celebrated annually on May 20. The holiday was established by the International Committee of Weights and Measures (CIPM) in October 1999, at the 88th meeting of the CIPM.

The formation and differences of metrology in the USSR (Russia) and abroad

The rapid development of science, technology and technology in the twentieth century required the development of metrology as a science. In the USSR, metrology developed as a state discipline, as the need to improve the accuracy and reproducibility of measurements grew with industrialization and the growth of the military-industrial complex. Foreign metrology was also based on practical requirements, but these requirements came mainly from private firms. An indirect consequence of this approach was government regulation various concepts related to metrology, that is, GOST standards for everything that needs to be standardized. Abroad, non-governmental organizations such as ASTM have taken on this task.

Due to this difference in metrology of the USSR and post-Soviet republics state standards(standards) are recognized as dominant, in contrast to the competitive Western environment, where a private company may not use an objectionable standard or instrument and agree with its partners on another option for certifying the reproducibility of measurements.

Selected areas of metrology

Aviation metrology
Chemical metrology
Medical metrology
Biometrics

The science of measurements, methods and means of ensuring their unity and ways of achieving the required accuracy.

MEASUREMENT

UNITY OF MEASUREMENT

1. Physical quantities

PHYSICAL QUANTITY (PV)

ACTUAL PV VALUE

PHYSICAL PARAMETER

Influential fv

ROD FV

Qualitative certainty FV.

Part length and diameter-

UNIT FV

PV UNIT SYSTEM

DERIVATIVE UNIT

Unit of speed- meter/second.

NON-SYSTEM UNIT FV

allowed equally;.

temporarily admitted;

withdrawn from use.

For example:

- - units of time;

in optics- diopter- - hectare- - unit of energy, etc.;

- revolutions per second; bar- pressure unit (1bar = 100 000 Pa);

quintal, etc.

MULTIPLE UNIT OF FV

DOLNAYA FV

For example, 1µs= 0.000 001s.

Basic terms and definitions metrology

The science of measurements, methods and means of ensuring their unity and ways of achieving the required accuracy.

MEASUREMENT

Finding the value of a measured physical quantity experimentally using special technical means.

UNITY OF MEASUREMENT

A characteristic of the quality of measurements, which consists in the fact that their results are expressed in legal units, and the errors of the measurement results are known with a given probability and do not go beyond the established limits.

ACCURACY OF MEASUREMENT RESULTS

A characteristic of the quality of a measurement, reflecting the closeness to zero of the error of its result.

1. Physical quantities

PHYSICAL QUANTITY (PV)

Characteristics of one of the properties of a physical object ( physical system, phenomenon or process), common in qualitative terms to many physical objects, but quantitatively individual for each object.

THE TRUE VALUE OF A PHYSICAL QUANTITY

The value of a physical quantity that ideally reflects the corresponding physical quantity in qualitative and quantitative terms.

This concept is correlated with the concept of absolute truth in philosophy.

ACTUAL PV VALUE

The value of the PV, found experimentally and so close to the true value that for the given measurement task it can replace it.

When checking measuring instruments, for example, the actual value is the value of the standard measure or the reading of the standard measuring instrument.

PHYSICAL PARAMETER

EF, considered when measuring a given EF as an auxiliary characteristic.

For example, frequency when measuring AC voltage.

Influential fv

PV, the measurement of which is not provided for by a given measuring instrument, but which influences the measurement results.

ROD FV

Qualitative certainty FV.

Part length and diameter- homogeneous quantities; the length and mass of the part are non-uniform quantities.

UNIT FV

A PV of a fixed size, which is conventionally assigned a numerical value equal to one, and is used for the quantitative expression of homogeneous PV.

There must be as many units as there are PVs.

There are basic, derivative, multiple, submultiple, systemic and non-systemic units.

PV UNIT SYSTEM

A set of basic and derived units of physical quantities.

BASIC UNIT OF THE SYSTEM OF UNITS

The unit of basic PV in a given system of units.

Basic units of the International System of Units SI: meter, kilogram, second, ampere, kelvin, mole, candela.

ADDITIONAL UNIT SYSTEM OF UNITS

There is no strict definition. In the SI system, these are the units of plane - radians - and solid - steradians - angles.

DERIVATIVE UNIT

A unit of a derivative of a PV system of units, formed in accordance with an equation connecting it with the basic units or with the basic and already defined derived units.

Unit of speed- meter/second.

NON-SYSTEM UNIT FV

The PV unit is not included in any of the accepted systems of units.

Non-systemic units in relation to the SI system are divided into four types:

allowed equally;.

approved for use in special areas;

temporarily admitted;

withdrawn from use.

For example:

ton: degree, minute, second- angle units; liter; minute, hour, day, week, month, year, century- units of time;

in optics- diopter- unit of measurement of optical power; in agriculture- hectare- unit of area; in physics electron-volt- unit of energy, etc.;

in maritime navigation, nautical mile, knot; in other areas- revolutions per second; bar- pressure unit (1bar = 100 000 Pa);

kilogram-force per square centimeter; millimeter of mercury; Horsepower;

quintal, etc.

MULTIPLE UNIT OF FV

A PV unit is an integer number of times larger than a system or non-system unit.

For example, frequency unit 1 MHz = 1,000,000 Hz

DOLNAYA FV

A PV unit is an integer number of times smaller than a system or non-system unit.

For example, 1µs= 0.000 001s.

Basic terms and definitions in metrology

Metrology– the science of measurements, methods and means of ensuring their unity and methods of achieving the required accuracy.

Direct measurement– a measurement in which the desired value of a physical quantity is obtained directly.

Indirect measurement– determination of the desired value of a physical quantity based on the results of direct measurements of other physical quantities that are functionally related to the desired quantity.

True value of a physical quantity– the value of a physical quantity that ideally characterizes the corresponding physical quantity in qualitative and quantitative terms.

Real value of a physical quantity– the value of a physical quantity obtained experimentally and so close to the true value that it can be used instead of it in the given measurement task.

Measured physical quantity– physical quantity to be measured in accordance with the main purpose of the measurement task.

Influential physical quantity– a physical quantity that influences the size of the measured quantity and (or) the result of measurements.

Normal range of influence quantities– the range of values of the influencing quantity, within which the change in the measurement result under its influence can be neglected in accordance with established accuracy standards.

Working range of influencing quantities– range of values of the influencing quantity, within which the additional error or change in the readings of the measuring instrument is normalized.

Measuring signal– a signal containing quantitative information about the measured physical quantity.

Scale division price– the difference in values corresponding to two adjacent scale marks.

Measuring instrument reading range– range of instrument scale values, limited by the initial and final scale values.

Measuring range– range of values of a quantity within which the permissible error limits of the measuring instrument are normalized.

Variation in meter readings– the difference in instrument readings at the same point in the measurement range with a smooth approach to this point from smaller and larger values of the measured value.

Transducer conversion factor– the ratio of the signal at the output of the measuring transducer, which displays the measured value, to the signal causing it at the input of the transducer.

Sensitivity of the measuring instrument– property of a measuring instrument, determined by the ratio of the change in the output signal of this instrument to the change in the measured value that causes it

Absolute error of the measuring instrument– the difference between the reading of a measuring instrument and the true (actual) value of the measured quantity, expressed in units of the measured physical quantity.

Relative error of the measuring instrument– error of a measuring instrument, expressed as the ratio of the absolute error of the measuring instrument to the measurement result or to the actual value of the measured physical quantity.

Reduced error of the measuring instrument– relative error, expressed as the ratio of the absolute error of the measuring instrument to the conventional accepted value a quantity (or standard value) that is constant over the entire measurement range or part of the range. Often the reading range or upper measurement limit is taken as the normalizing value. The given error is usually expressed as a percentage.

Systematic error of the measuring instrument– component of the error of a measuring instrument, taken as constant or naturally varying.

Random error of the measuring instrument– component of the error of the measuring instrument, varying randomly.

Basic error of the measuring instrument– error of the measuring instrument used under normal conditions.

Additional error of the measuring instrument– a component of the error of a measuring instrument that arises in addition to the main error as a result of the deviation of any of the influencing quantities from its normal value or as a result of going beyond the normal range of values.

Limit of permissible error of measuring instrument – highest value error of measuring instruments, established by a regulatory document for a given type of measuring instrument, at which it is still recognized as suitable for use.

Measuring instrument accuracy class– a generalized characteristic of a given type of measuring instrument, usually reflecting the level of their accuracy, expressed by the limits of permissible main and additional errors, as well as other characteristics affecting the accuracy.

Measurement result error– deviation of the measurement result from the true (actual) value of the measured quantity.

Miss (gross measurement error)– the error of the result of an individual measurement included in a series of measurements, which, for given conditions, differs sharply from the other results of this series.

Measurement method error– component of the systematic measurement error due to the imperfection of the adopted measurement method.

Amendment– the value of the quantity entered into the uncorrected measurement result in order to eliminate the components of the systematic error. The sign of the correction is opposite to the sign of the error. The correction introduced into the reading of a measuring device is called an amendment to the reading of the device.

Basic terms and definitions metrology

The science of measurements, methods and means of ensuring their unity and ways of achieving the required accuracy.

MEASUREMENT

Finding the value of a measured physical quantity experimentally using special technical means.

UNITY OF MEASUREMENT

ACCURACY OF MEASUREMENT RESULTS

A characteristic of the quality of a measurement, reflecting the closeness to zero of the error of its result.

1. Physical quantities

PHYSICAL QUANTITY (PV)

A characteristic of one of the properties of a physical object (physical system, phenomenon or process), which is qualitatively common to many physical objects, but quantitatively individual for each object.

THE TRUE VALUE OF A PHYSICAL QUANTITY

The value of a physical quantity that ideally reflects the corresponding physical quantity in qualitative and quantitative terms.

This concept is correlated with the concept of absolute truth in philosophy.

ACTUAL PV VALUE

The value of the PV, found experimentally and so close to the true value that for the given measurement task it can replace it.

When checking measuring instruments, for example, the actual value is the value of the standard measure or the reading of the standard measuring instrument.

PHYSICAL PARAMETER

EF, considered when measuring a given EF as an auxiliary characteristic.

For example, frequency when measuring AC voltage.

Influential fv

PV, the measurement of which is not provided for by a given measuring instrument, but which influences the measurement results.

ROD FV

Qualitative certainty FV.

Part length and diameter- homogeneous quantities; the length and mass of the part are non-uniform quantities.

UNIT FV

A PV of a fixed size, which is conventionally assigned a numerical value equal to one, and is used for the quantitative expression of homogeneous PV.

There must be as many units as there are PVs.

There are basic, derivative, multiple, submultiple, systemic and non-systemic units.

PV UNIT SYSTEM

A set of basic and derived units of physical quantities.

BASIC UNIT OF THE SYSTEM OF UNITS

The unit of basic PV in a given system of units.

Basic units of the International System of Units SI: meter, kilogram, second, ampere, kelvin, mole, candela.

ADDITIONAL UNIT SYSTEM OF UNITS

There is no strict definition. In the SI system, these are the units of plane - radians - and solid - steradians - angles.

DERIVATIVE UNIT

A unit of a derivative of a PV system of units, formed in accordance with an equation connecting it with the basic units or with the basic and already defined derived units.

Unit of speed- meter/second.

NON-SYSTEM UNIT FV

The PV unit is not included in any of the accepted systems of units.

Non-systemic units in relation to the SI system are divided into four types:

allowed equally;.

approved for use in special areas;

temporarily admitted;

withdrawn from use.

For example:

ton: degree, minute, second- angle units; liter; minute, hour, day, week, month, year, century- units of time;

in optics- diopter- unit of measurement of optical power; in agriculture- hectare- unit of area; in physics electron-volt- unit of energy, etc.;

in maritime navigation, nautical mile, knot; in other areas- revolutions per second; bar- pressure unit (1bar = 100 000 Pa);

kilogram-force per square centimeter; millimeter of mercury; Horsepower;

quintal, etc.

MULTIPLE UNIT OF FV

A PV unit is an integer number of times larger than a system or non-system unit.

For example, frequency unit 1 MHz = 1,000,000 Hz

DOLNAYA FV

A PV unit is an integer number of times smaller than a system or non-system unit.

For example, 1µs= 0.000 001s.

Metrology Basic terms and definitions

UDC 389.6(038):006.354 Group T80

STATE SYSTEM FOR ENSURING THE UNIFORMITY OF MEASUREMENTS

State system for ensuring the uniformity of measurements.

Metrology. Basic terms and definitions

ISS 01.040.17

Date of introduction 2001-01-01

Preface

1 DEVELOPED by the All-Russian Scientific Research Institute of Metrology named after. D.I. Mendeleev Gosstandart of Russia

INTRODUCED by the Technical Secretariat of the Interstate Council for Standardization, Metrology and Certification

2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 15 of May 26-28, 1999)

State name	Name of the national standardization body
The Republic of Azerbaijan	Azgosstandart
Republic of Armenia	Armgosstandard
Republic of Belarus	State Standard of Belarus
	Gruzstandart
The Republic of Kazakhstan	Gosstandart of the Republic of Kazakhstan
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
The Republic of Tajikistan	Tajikgosstandart
Turkmenistan	Main State Inspectorate of Turkmenistan
The Republic of Uzbekistan	Uzgosstandart
	State Standard of Ukraine

3 By Decree of the State Committee of the Russian Federation for Standardization and Metrology dated May 17, 2000 No. 139-st, interstate Recommendations RMG 29-99 were put into effect directly as Recommendations for Metrology of the Russian Federation from January 1, 2001.

4 INSTEAD GOST 16263-70

5 REPUBLICATION. September 2003

Amendment No. 1 was introduced, adopted by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 24 of December 5, 2003) (IUS No. 1 of 2005)

Introduction

The terms established by these recommendations are arranged in a systematic order, reflecting the established system of basic concepts of metrology. Terms are given in sections 2-13. Each section contains continuous numbering of terms.

For each concept, one term is established, which has a terminological article number. A significant number of terms are accompanied by their short forms and (or) abbreviations, which should be used in cases that exclude the possibility of their different interpretations.

Terms that have the number of a terminological article are typed in bold, their short forms and abbreviations are in light. Terms appearing in the notes are in italics.

In the alphabetical index of terms in Russian, the specified terms are listed in alphabetical order, indicating the number of the terminological article (for example, “value 3.1”). In this case, for terms given in the notes, the letter “p” is indicated after the article number (for example, legalized units 4.1 p).

For many established terms, foreign language equivalents are provided in German (de), English (en) and French (fr). They are also given in alphabetical indexes equivalent terms in German, English and French.

The word “applied” in term 2.4, given in brackets, as well as the words of a number of foreign language equivalents of terms given in brackets, can be omitted if necessary.

The concept of “additional unit” is not defined, since the term fully discloses its content.

Basic metrology terms are established by state standards.

1. Basic concept of metrology — measurement. According to GOST 16263-70, measurement is finding the value of a physical quantity (PV) experimentally using special technical means.

The result of a measurement is the obtaining of a value during the measurement process.

2. Measuring instrument(SI) is a special technical means that stores a unit of quantity for comparing the measured quantity with its unit.

3. Measure is a measuring instrument designed to reproduce a physical quantity of a given size: weights, gauge blocks.

To assess the quality of measurements, the following measurement properties are used: accuracy, convergence, reproducibility and accuracy.

- Correctness- the property of measurements when their results are not distorted by systematic errors.

- Convergence- a property of measurements that reflects the closeness to each other of the results of measurements performed under the same conditions, by the same SI, by the same operator.

For example, the same resistance can be measured directly with an ohmmeter, or with an ammeter and a voltmeter using Ohm's law. But, naturally, in both cases the results should be the same.

- Accuracy- a property of measurements that reflects the closeness of their results to the true value of the measured quantity.

This is the main property of measurements, because most widely used in the practice of intentions.

The accuracy of SI measurements is determined by their error. High measurement accuracy corresponds to small errors.

4.Error is the difference between the SI readings (measurement result) Xmeas and the true (actual) value of the measured physical quantity Xd.

Previously, legal norms were established by government regulations.

Compared to the provisions of these resolutions, the Law established the following innovations:

In terminology, outdated concepts and terms have been replaced;

In licensing metrological activities in the country, the right to issue a license is granted exclusively to the bodies of the State Metrological Service;

A unified verification of measuring instruments has been introduced;

A clear separation of the functions of state metrological control and state metrological supervision has been established.

An innovation is also the expansion of the scope of state metrological supervision to banking, postal, tax, customs operations, as well as to mandatory certification of products and services;

Calibration rules have been revised;

Voluntary certification of measuring instruments has been introduced, etc.

Prerequisites for the adoption of the law:

The result was the reorganization of state metrological services;

This led to a disruption of the centralized management system for metrological activities and departmental services;

Problems arose during state metrological supervision and control due to the emergence of various forms of ownership;

Thus, the problem of revising the legal, organizational, and economic foundations of metrology has become very urgent.

The objectives of the Law are as follows:

Protection of citizens and the economy of the Russian Federation from the negative consequences of unreliable measurement results;

Promoting progress based on the use of state standards of units of quantities and the use of measurement results of guaranteed accuracy;

Creating favorable conditions for the development of international relations;

Regulation of relations between government bodies of the Russian Federation and legal entities and individuals on issues of manufacturing, production, operation, repair, sale and import of measuring instruments.

Consequently, the main areas of application of the Law are trade, healthcare, environmental protection, and foreign economic activity.

The task of ensuring the uniformity of measurements is assigned to the State Metrological Service. The law determines the intersectoral and subordinate nature of its activities.

The intersectoral nature of the activity means the legal status of the State Metrological Service is similar to other control and supervisory government bodies (Gosatomnadzor, Gosenergonadzor, etc.).

The subordinate nature of its activities means vertical subordination to one department - Gosstandart of Russia, within the framework of which it exists separately and autonomously.

In pursuance of the adopted Law, the Government of the Russian Federation in 1994 approved a number of documents:

- “Regulations on state scientific and metrological centers”,

- “The procedure for approving regulations on metrological services of federal executive authorities and legal entities”,

- “The procedure for accreditation of metrological services of legal entities for the right to verify measuring instruments”,

These documents, together with the specified Law, are the main legal acts on metrology in Russia.

The word "metrology" is formed from two Greek words: "metron" - measure and logos - doctrine. The literal translation of the word “metrology” is the study of measures. For a long time, metrology remained mainly a descriptive science about various measures and the relationships between them. Since the end of the last century, thanks to the progress of the physical sciences, metrology has received significant development. A major role in the development of modern metrology as one of the sciences of the physical cycle was played by D. I. Mendeleev, who led domestic metrology in the period 1892 - 1907.

Metrology, in its modern understanding, is the science of measurements, methods, means of ensuring their unity and methods of achieving the required accuracy.

Under uniformity of measurements understand the state of measurements in which their results are expressed in standardized units and measurement errors are known with a given probability. Unity of measurements is necessary so that the results of measurements taken at different places can be compared in different time, using different methods and measuring instruments.

The accuracy of measurements is characterized by the closeness of their results to the true value of the measured value. Since absolutely accurate instruments do not exist, the accuracy of instruments can only be discussed in terms of probability theory and mathematical statistics. The most important task of metrology is to improve standards, develop new methods of precise measurements, and ensure uniformity and the necessary accuracy of measurements.

Metrology includes the following sections:

1. Theoretical metrology, where general issues of measurement theory are considered.

2. Applied metrology studies issues of practical application of the results of theoretical research

3. Legal metrology considers a set of rules, norms and requirements regulated by government bodies to ensure uniformity of measurements and uniformity of measuring instruments.

Under measurement understand the process of obtaining quantitative information about the value of any physical quantity experimentally using measuring instruments.

Physical quantity- this is a property that is qualitatively common to many physical objects (systems, their states and processes occurring in them), but quantitatively individual for each object.

Unit of physical quantity is a physical quantity, the size of which is assigned a numerical value of 1. The size of a physical quantity is the quantitative content in a given object of a property corresponding to the concept of “physical quantity”.

For each physical quantity, a unit of measurement must be established. All physical quantities are interconnected by dependencies. Their totality can be considered as system of physical quantities. Moreover, if you select several physical quantities for basic, then other physical quantities can be expressed through them.

All units of measurement are divided into basic and derivatives(derived from the main ones). An expression reflecting the relationship of a physical quantity with the basic physical quantities of the system is called dimension of physical quantity.

Some concepts of dimensional theory

The operation of determining the dimension of a physical quantity x will be denoted by the corresponding capital letter

The theory of dimensions is based on the following statements (theorems)

1. The dimensions of the left and right parts must always match, i.e.

if there is some expression like

2. The algebra of dimensions is multicative, i.e. for dimensions, a multiplication operation is defined, and the operation of multiplying several quantities is equal to the product of their dimensions

3. The dimension of the quotient of dividing two quantities is equal to the ratio of their dimensions

4. The dimension of a quantity raised to a power is equal to the dimension of a quantity raised to the corresponding power

The operations of addition and subtraction of dimensions are not defined.

From the provisions of the theory of dimensionality it follows that the dimension of one physical quantity related by certain relationships with other physical quantities (i.e., for a quantity included in a system of physical quantities) can be expressed through the dimensions of these quantities.

The dimension of a physical quantity is its qualitative characteristics.

Metrology - the science of measurements, methods and means of ensuring their unity and methods of achieving the required accuracy.

Unity of measurements- the state of measurements, characterized by the fact that their results are expressed in legal units, the sizes of which, within established limits, are equal to the sizes of units reproduced by primary standards, and the errors of the measurement results are known and with a given probability do not go beyond the established limits.

Physical quantity- one of the properties of a physical object (physical system, phenomenon or process), common in qualitative terms for many physical objects, but quantitatively individual for each of them.

True value of a physical quantity- the value of a physical quantity that ideally characterizes the corresponding physical quantity in qualitative and quantitative terms.

The true size of a physical quantity is objective reality, which does not depend on whether it is measured or not and which ideally characterizes the properties of the object.

Since we do not know the true meaning, the concept of actual meaning is used instead.

Real value of a physical quantity- the value of a physical quantity obtained experimentally and so close to the true value that it can be used instead of it in the given measurement task.

Physical quantity scale- an ordered set of values of a physical quantity that serves as the initial basis for measuring a given quantity.

Measurement - a set of operations for the use of a technical means that stores a unit of physical quantity, ensuring that the relationship (explicitly or implicitly) of the measured quantity with its unit is found and the value of this quantity is obtained.

Measurement is the process of comparing the desired quantity with a quantity whose size is equal to 1.

Q=n*[Q] - measurement equation,

Q - Measured physical quantity,

[Q] - qualitative characteristic of PV,

n- Quantitative characteristics, which shows how many times the measured value differs from the value whose size is taken as a unit.

[Q] - its size is taken as one. For example, the part size is 20 mm, we compare the size with 1 mm.

Measuring task- a task consisting in determining the value of a physical quantity by measuring it with the required accuracy under given measurement conditions.

According to the method of obtaining information, measurements are divided:

1. Direct measurements - measurements in which the desired value of a physical quantity is found directly from experimental data, and they can be expressed as Q = x, where Q is the desired value of the measured quantity, and x is the value obtained from experimental data. For example, measuring body length using a SC, ruler, etc. measurement is carried out using SI, the scales of which are graduated in units of the measured value.

Direct measurements form the basis of all subsequent measurements.

2. Indirect measurements(indirect measurement method) - determination of the desired value of a physical quantity based on the results of direct measurements of other physical quantities that are functionally related to the desired quantity. For example, the volume of the part is Q=V=S*h.

3. Aggregate Measurements- simultaneous measurements of several quantities of the same name, in which the required values of the quantities are determined by solving a system of equations obtained by measuring these quantities in various combinations (the number of equations must be at least the number of quantities). For example, determining body weight using weights; determination of resistance, inductance for series and parallel connections.

4. Joint measurements- simultaneous measurements of two or more different quantities to determine the relationship between them. Non-identical quantities differ in nature. For example, it is necessary to determine the dependence of resistance on temperature, pressure

Measurement characteristics:

Measuring principle - physical phenomenon or the effect underlying the measurements.

Measurement method- a technique or set of techniques for comparing a measured physical quantity with its unit in accordance with the implemented measurement principle.

Basic measurement methods:

· Direct assessment method- a measurement method in which the value of a quantity is determined directly from the indicating measuring instrument.

· Comparison method with measure- a measurement method in which the measured value is compared with the value reproduced by the measure. Methods of comparison with a measure:

o a) Zero measurement method- a method of comparison with a measure, in which the resulting effect of the influence of the measured quantity and measure on the comparison device is brought to zero.

o b) Substitution measurement method- a method of comparison with a measure, in which the measured quantity is replaced by a measure with a known value of the quantity.

o c) Measurement method by addition- a method of comparison with a measure, in which the value of the measured quantity is supplemented with a measure of the same quantity in such a way that the comparison device is affected by their sum equal to a predetermined value.

o d) Differential measurement method- a measurement method in which the measured quantity is compared with a homogeneous quantity having a known value that differs slightly from the value of the measured quantity, and in which the difference between these quantities is measured.

Measurement error

Accuracy of measurements- one of the characteristics of measurement quality, reflecting the closeness to zero error of the measurement result.

Convergence of measurement results- proximity to each other of the results of measurements of the same quantity, performed repeatedly using the same means, the same method under the same conditions and with the same care.

Reproducibility of measurement results- closeness of measurement results of the same quantity obtained in different places, by different methods, by different means, by different operators, at different times, but reduced to the same measurement conditions (temperature, humidity, etc.) (reproducibility can characterized by the mean square errors of the compared series of measurements).

Measuring instrument - a technical device intended for measurements, having standardized metrological characteristics, reproducing and (or) storing a unit of physical quantity, the size of which is assumed to be unchanged (within the established error) for a known time interval.

Type of measuring instruments- a set of measuring instruments intended for measuring quantities of a certain type (means for measuring mass, linear quantities...).

Classification of measuring instruments:

1. Measure- a measuring instrument intended for reproducing and (or) storing a physical quantity of one or more specified sizes, the values of which are expressed in established units and known with the required accuracy (single-valued, multi-valued measures, a set of measures, a magazine of measures).

o Unambiguous measure- a measure that reproduces a physical quantity of the same size.

o Set of measures- a set of measures of different sizes of the same physical quantity, intended for use in practice, both individually and in various combinations (set of KMD).

o Store measures- a set of measures structurally combined into a single device, which contains devices for connecting them in various combinations (for example, a store of electrical resistances).

Nominal value of the measure- the value of a quantity assigned to a measure or batch of measures during manufacture. Real value of the measure- the value of a quantity assigned to a measure based on its calibration or verification.

2. Measuring device- a measuring instrument designed to obtain values of a measured physical quantity within a specified range.

3. Measuring setup- a set of functionally combined measures, measuring instruments, measuring transducers and other devices, designed to measure one or more physical quantities and located in one place.

4. Measuring system- a set of measuring instruments forming measuring channels, computing and auxiliary devices, functioning as a single whole and intended for automatic (automated) obtaining information about the state of an object through measurement transformations in the general case, a set of time-varying and spatially distributed quantities characterizing this state ; machine processing of measurement results; registration and indication of measurement results and machine processing results; converting this data into system output signals. Measuring systems satisfy the characteristics of measuring instruments and are classified as measuring instruments.

5. Measuring transducer.

6. Measuring machine.

7. Measuring accessories- auxiliary means used to ensure necessary conditions to perform measurements with the required accuracy (they are not a measuring instrument).

Metrological characteristics of measuring instruments- characteristics of the properties of the measuring instrument that influence the results and measurement errors, intended to assess the technical level and quality of the measuring instrument, to determine the measurement results and calculate the characteristics of the instrumental component of the measurement error.

Scale- part of the indicating device of a measuring instrument, which is an ordered series of marks along with the numbering associated with it.

Scale division- the gap between two adjacent marks on the scale of a measuring instrument.

Scale division price- the difference between the values of a quantity corresponding to two adjacent marks on the scale of a measuring instrument.

Initial scale value- the smallest value of the measured quantity that can be counted on the scale of the measuring instrument.

End scale value- the largest value of the measured quantity that can be counted on the scale of the measuring instrument.

Variation in meter readings- the difference in instrument readings at the same point in the measurement range with a smooth approach to this point from smaller and larger values of the measured value.

Reading range- the range of the instrument scale value, limited by the initial and final values of the scale.

Measuring range- the range of values of the quantity within which the permissible error limits of the measuring instrument are normalized.

Dynamic characteristics of the measuring instrument- MX properties of a measuring instrument, manifested in the fact that the output signal of this measuring instrument is influenced by the values of the input signal and any changes in these values over time.

Measuring instrument stability- a qualitative characteristic of a measuring instrument, reflecting the constancy of its characteristics over time.

Errors of measuring instruments and measurements:

Nothing can be measured absolutely accurately. The measurement result depends on many factors: - the used measurement method,

The applied SI,

Measurement conditions,

From the method of processing measurement results,

Operator qualifications, etc.

These factors have different effects on the difference between the measurement result and the true value of the quantity. First of all: 1) there is an error from replacing the true value with the actual one. 2) the error of the measurement method used, with each method making a certain contribution to the error. 3) Because Any dependence between the measured quantity and other quantities is derived on the basis of certain assumptions, then when using this dependence, a theoretical (methodological) error is allowed. 4) The measuring instrument itself is a source of error, because its imperfection, distortion characteristic features measured quantity (input signal) received at the SI input during the measurement process. transformations.

Measuring instrument error - the difference between the reading of the measuring instrument and the true (actual) value of the measured physical quantity.

Measurement error - deviation of the measurement result from the true (actual) value of the measured quantity (the true value of the quantity is unknown, it is used only in theoretical research. In practice, the actual value of the quantity is used)

Error of the measuring instrument in the interval of the influencing quantity- error of the measuring instrument in conditions when one of the influencing quantities takes any value within the working range of its values, and the remaining influencing quantities are within the limits corresponding to normal conditions (GOST 8.050-73 " Normal conditions performing linear and angular measurements"). Note: The error of the measuring instrument in the interval of the influencing quantity is not an additional error, since the latter is caused only by the difference in the value of the influencing quantity from the normal value.

Systematic error- component of the error of a measurement result that remains constant or changes naturally during repeated measurements of the same physical quantity.

Instrumental error- component of the measurement error due to the error of the measuring instrument used.

Method error- component of the systematic measurement error due to the imperfection of the adopted measurement method.

Subjective error- component of the systematic measurement error due to the individual characteristics of the operator.

Random error- component of the error of the measurement result, changing randomly (in sign and value) during repeated measurements, carried out with the same care, of the same physical quantity.

Absolute error- measurement error, expressed in units of the measured value.

Relative error- measurement error, expressed as the ratio of the absolute measurement error to the actual or measured value of the measured quantity.

Systematic error component measuring instrument - a component of the error of a given instance of a measuring instrument, with the same value of the measured or reproducible quantity and unchanged conditions of use of the measuring instrument, remaining constant or changing so slowly that its changes during the measurement can be neglected, or changing according to a certain law, if conditions change.

Random component of the measuring instrument error- random component of the error of a measuring instrument, due only to the properties of the measuring instrument itself; represents a centered random variable or a centered random process.

Error of the result of a single measurement- the error of one measurement (not included in a series of measurements), estimated on the basis of the known errors of the instrument and method of measurement under given conditions.

Total error- error of the measurement result (consisting of the sum of random and non-excluded systematic errors accepted as random), calculated by the formula.

Accuracy class of measuring instruments- a generalized characteristic of a given type of measuring instrument, usually reflecting the level of their accuracy, expressed by the limits of permissible main and additional errors, as well as other characteristics affecting the accuracy.

Accuracy classes of measuring instruments

The limits of permissible basic error are set in the sequence given below.

The limits of permissible absolute basic error are established by the formula:

or, (2)

where Δ is the limits of the permissible absolute basic error, expressed in units of the measured value at the input (output) or conventionally in scale divisions;

x - the value of the measured quantity at the input (output) of the measuring instruments or the number of divisions counted on the scale;

a, b are positive numbers independent of x.

In justified cases, the limits of permissible absolute error are established using a more complex formula or in the form of a graph or table.

The limits of the permissible given basic error should be set according to the formula

, (3)

where γ - limits of permissible reduced basic error, %

Δ - limits of permissible absolute basic error, established by formula (1);

X N – normalizing value, expressed in the same units as Δ;

p - an abstract positive number selected from the series 1∙10 n; 1.5∙10 n ;(1.6∙10 n);2∙10 n ;2.5∙10 n ;(3∙10 n);4∙10 n ;5∙10 n ;6∙10 n ( n=1, 0, -1, -2, etc.) (*)

The values indicated in brackets are not established for newly developed measuring instruments.

The normalizing value X N for measuring instruments with a uniform, almost uniform or power scale, as well as for measuring transducers, if the zero value of the input (output) signal is at the edge or outside the measurement range, should be set equal to the greater of the measurement limits or equal to the greater of the module limits measurements if the zero value is within the measurement range.

For electrical measuring instruments with a uniform, almost uniform or power scale and a zero mark within the measurement range, the normalizing value can be set equal to the sum of the modules of the measurement limits.

For measuring instruments of a physical quantity, for which a scale with a conditional zero is adopted, the normalizing value is set equal to the modulus of the difference in the measurement limits.

For measuring instruments with a specified nominal value, the normalizing value is set equal to this nominal value.

The limits of permissible relative basic error are established by the formula:

if Δ is established by formula (1) or by formula

, (5)

where δ - limits of permissible relative basic error, %

q – abstract positive number,

X k – the largest (in absolute value) of the measurement limits,

c and d are positive numbers chosen from the series (*).

In justified cases, the limits of the permissible relative basic error are established using a more complex formula or in the form of a graph or table.

Accuracy classes, which correspond to smaller limits of permissible errors, should correspond to letters located closer to the beginning of the alphabet, or numbers representing smaller numbers.

In the operational documentation for a measuring instrument of a specific type, containing a designation of the accuracy class, there must be a reference to the standard or technical specifications, in which the accuracy class of this measuring instrument is established.

Construction rules and examples of designation of accuracy classes in documentation and on measuring instruments are given in the table.

An almost uniform scale is a scale whose length of divisions differs from each other by no more than 30% and has a constant value of divisions.

Error expression form	Limits of permissible basic error	Limits of permissible basic error, %	Accuracy class designation
in the documentation	on the measuring instrument
Given by	According to formula (3): if the normalizing value is expressed in units of value at the input (output) of the measuring instruments, if the normalizing value is taken equal to the length of the scale or part of it		Accuracy class 1.5 Accuracy class 0.5	1,5 0,5
Relative by	According to formula (4) According to formula (5)		Accuracy class 0.5 Accuracy class 0.02/0.01	0,02/0,01
Absolute by	According to formula (1) or (2)		Accuracy class M Accuracy class C	M S

Normal conditions for performing linear and angular measurements

Depending on the measurement conditions, errors are divided into: basic and additional.

The main error is the error corresponding to the normal conditions that are established by regulatory documents for types of SI.

Normal conditions must be ensured during measurements to practically eliminate additional errors.

Normal values of the main influencing quantities:

1. Ambient temperature 20 o C according to GOST 9249-59.

2. Atmospheric pressure 101325 Pa (760 mm Hg).

3. Relative ambient humidity 58% (normal partial pressure of water vapor 1333 Pa).

4. Gravity acceleration (gravity acceleration) 9.8 m/s 2 .

5. The direction of the line and plane of measurement of linear dimensions is horizontal (90 o from the direction of gravity).

6. The position of the angle measurement plane is horizontal (90° from the direction of gravity).

7. The relative speed of movement of the external environment is zero.

8. Values of external forces, except gravity, atmospheric pressure, action magnetic field The earth and adhesion forces of the elements of the measuring system (installation) are equal to zero.

For comparability, measurement results must be reduced to normal values of influencing quantities with an error not exceeding 35% of the permissible measurement error.

Processing of measurement results with multiple independent observations:

It is required to study a set of homogeneous objects with respect to some qualitative or quantitative feature characterizing the object ( qualitative sign- standardization of the part, quantitative - controlled parameter of the part). Sometimes a complete survey is carried out, that is, each of the objects in the population is examined. In practice, this is difficult to implement, since the collection contains a very large number of objects. Therefore, in such cases, a limited number of objects (sample) are randomly selected from the population to be studied. Based on the results obtained, a conclusion is drawn about the entire population.

Sample population (sample)- a collection of randomly selected objects.

Population- the entire set of objects from which the sample is made.

Measurement result- the value of a quantity obtained by measuring it.

A range of results- values of the same quantity, successively obtained from successive measurements.

Dispersion of results in a series of measurements- discrepancy between the results of measurements of the same quantity in a series of equal-precision measurements, as a rule, due to the effect of random errors. Estimates of the dispersion of results in a series of measurements can be: range, arithmetic mean error (modulo), root mean square error (modulo), root mean square error or standard deviation (standard deviation, experimental standard deviation).

Range of measurement results- estimate R n of the scattering of the results of single measurements of a physical quantity forming a series (or sample of n measurements), calculated by the formula

where X max and X min are the largest and smallest values of a physical quantity in a given series of measurements (scattering is usually caused by the manifestation of random causes during measurement and is probabilistic in nature).

The results of observations are largely concentrated around the true value of the measured quantity, and as we approach it, the elements of the probability of their occurrence increase. With multiple measurements, information about the true value of the measured quantity and the dispersion of observation results consists of a number of results of individual observations X 1, X 2, ... X n, where n is the number of observations. They can be considered as n independent random variables. In this case, the arithmetic mean of the obtained observation results can be taken as an estimate of the measured value.

The arithmetic mean is only an estimate of the mathematical expectation (ME) of the measurement result and can become an estimate of the true value of the measured value only after systematic errors have been eliminated.

Of particular importance, along with the MO of measurement results, is the dispersion - the characteristic of the dispersion of results relative to the MO. Dispersion is not always convenient to use, so the standard deviation of observation results is used.

Root mean square error of the results of single measurements in a series of measurements(mean square error, MSE) - estimate S of the dispersion of single measurement results in a series of equally accurate measurements of the same physical quantity around their average value, calculated by the formula

where X i is the result of the i-th unit measurement,

The arithmetic mean of the measured value from n individual results.

When processing a number of measurement results free from systematic errors, the SKP and MSD are the same estimate of the dispersion of the measurement results.

Root mean square error of the arithmetic mean measurement result- shows the deviation of the sample average from the mathematical expectation.

where S is the root mean square error of the results of single measurements, obtained from a series of equally accurate measurements; n is the number of single measurements in a series.

Confidence limits of measurement error- the largest and smallest values of the measurement error, limiting the interval within which the desired (true) value of the measurement result error is located with a given probability. (Confidence limits in the case of a normal distribution law are calculated as ±t р ·S, where t р is a coefficient depending on the confidence probability P and the number of measurements n).

The confidence interval limits are defined as:

()

Amendment- the value of the quantity entered into the uncorrected measurement result in order to eliminate the components of the systematic error (the sign of the correction is opposite to the sign of the error).

Criterion for screening out misses for a predetermined confidence probability(Romanovsky criterion) - for all results X i that are not outliers (misses), the following conditions are met:

where t p is the quantile (coefficient).

Miss- the error of the result of an individual measurement included in a series of measurements, which, for given conditions, differs sharply from the other results of this series (miss - gross measurement error).

Maximum measurement error in a series of measurements- maximum measurement error (plus, minus) allowed for a given measurement task ().

A normal distribution of random variables occurs when the measurement result is influenced by many factors (random), none of which is predominant.

Normal distribution function:

where Xi – i-th value random variable(SV),

M[X] – mathematical expectation of SV,

σ x – standard deviation of an individual measurement result.

Normal distribution law.