Verification of measuring instruments: organization and procedure

In Russia for a long period of time there was the following practice in the field of metrology: permissible norms were established only by the relevant government regulations. It was necessary to adopt a corresponding law in this area. This was done in 1993. The Law "On ensuring the uniformity of measurements" was adopted.

Objectives

The main tasks of this normative act are:

• Protection of legitimate interests and rights of citizens of the Russian Federation in accordance with the current legislation in the field of measurement results;
• Assistance and support at the state level to economic and scientific and technical progress by introducing standard units, guaranteeing the accuracy of the application of the standards obtained;
• Creation of a favorable climate for the development of international relations;
• The formation of a unified system of standards for the unimpeded release, sale, operation, repair of manufactured in Russia and imported from abroad measuring instruments;
• Gradual bringing the measuring structure used in Russia to world standards.

Verification of measuring instruments according to 44-FZ

Let us consider this concept in more detail. Verification of means of measurement is a set of all actions that are performed by the State Metrology Service or other organizations of similar profile. To carry out activities, these institutions must have special permission and authority. Activities of organizations are aimed at confirming compliance of the measuring instrument with the requirements established by law. The main purpose of the activity is to determine the characteristics of the equipment under study, comparing them with the values established by the regulations. As a result of the evaluation, a conclusion is made about the possibility / impossibility of using the intended use in the documentation specified. Verification of means of measurement, performed by the authorized body or organization, is carried out using special metrological values. These parameters are determined experimentally. All new measuring devices, manufactured according to the relevant standards, in service, as well as devices subjected to repair influences, are subject to verification. The necessity to implement this activity is mandatory for the provision of standards (GREEE) used in the field of state regulation. The equipment used in other areas is tested on a voluntary basis.

Authorized bodies

Verification of measuring instruments is carried out by employees of special accredited metrological services. The personnel must undergo appropriate training, after which a special certificate is issued. Only after this, employees can perform such specialized work. Non-state enterprises, unlike state-owned enterprises, have the right to independently and without limitations choose the body that will be used to verify the measuring instruments. The organization and procedure for conducting the assessment is fixed at the legislative level. On the basis of the tender, state and municipal institutions are obliged to conclude contracts for the implementation of the activities by the authorized bodies. In cases where the result of the evaluation is positive, an appropriate certificate is issued or a special stamp is made (there are other ways provided by law).

Technical features

On the technical side, verification of measuring instruments is a procedure for comparing the physical quantity (in numerical terms) obtained with the equipment under test, with a reference value. Parameters, taken as the basis for comparison (standard), were obtained as a result of many-time evaluations by high-precision, serviceable devices. In this case, there is a limitation: the error of the standard must be at least three times less than the error of the measuring instrument passing through the verification. In accordance with the current legislation, such devices can be subjected to a primary, planned, unscheduled and inspection evaluation.

Primary comparison

The primary verification of measuring instruments is carried out for all instruments classified by type, shipped from production, repaired or imported from another country. There is a temporary restriction on the effect of the valuation performed. It is relevant only within the approved model certificate for each device. There are two types of verification: selective and each instance. The most common is the second option. Exceptions not subject to initial verification may include funds imported from abroad under the concluded international agreements. The contracts in this case impose an obligation to assess and award an international certificate to foreign manufacturers. The primary verification of measuring instruments is carried out at special control points organized by specialized agencies. Most of these items are located directly at the equipment manufacturers or repair shops for convenience and time saving. The results of such verification are valid for a certain period of time-the inter-calving period.

Planned evaluation

Such verification of measuring instruments (operated or stored) is carried out at strictly established time intervals. For each individual industry, special intervals have been developed, within which assessment is necessary. For example, verification of measuring instruments of medical purpose is performed more often than checking roulettes in cartography. In this case, unused appliances that are in a state of long-term storage, subject to certain rules (integrity of seals, packaging, storage in one place, etc.) may not be evaluated. When making comparisons, the owner (user) of the inspected facility must provide it in working order with a full set of documents attached to it: a passport, instructions for use, documents on the latest verification (if any) and all the accessories that are provided by the manufacturer. The bodies that make the appraisal of the equipment are required to keep a full record of the results of all their actions. Conclusions can be the basis for adjusting the verification interval. However, this correction is possible only in exceptional cases and only with the consent of the State Metrological Service. In disputable issues arising in this situation, the final decision is made by the GNMTS. In most cases, scheduled calibration of measuring instruments is carried out on the territory of the owner (user) by the equipment of the authorized body. At the same time, the right to choose the place of evaluation belongs to the user, taking into account his production and economic capabilities. In megacities, the transportation of equipment to the place of evaluation can have a significant impact. Therefore, for example, verification of measuring instruments in Moscow in certain cases can be carried out on the territory of the manufacturer or user.

Unscheduled Assessment

The frequency of such checks does not have a clear timeframe. Indications for its implementation can serve as the following cases:

- the stamp has been damaged;

- Certificate of verification has been lost;

- commissioning after prolonged storage;

- re-tuning or alignment;

- occurrence of errors in operation or due to impact.

Inspection verification

The purpose of this type of assessment is to identify the suitability of the devices being checked for metrological control at the state level. Its results are reflected in the relevant act. It is allowed to carry out such verification not in full, which is stipulated by the verification procedure.