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Frequently Asked Questions - Metrology

1. What is the difference between a working meter and a set meter? 

From the point of view of function, there is no difference between working and determined gauges, as both categories of gauges are used to determine the value of the measured quantity. However, since in some cases of measurement it is desirable that the correctness of the gauges and the objectivity of the measurements be guaranteed by the State, the gauges concerned are classified as established gauges. This category therefore includes, in particular, measuring instruments the reading of which may give rise to penalties or affect human health and, last but not least, measuring instruments used in commercial transactions.  

However, the two categories of measuring instruments differ in the way they are metrologically secured. The correctness of working measuring instruments is ensured by their user by calibration, whereas the correctness of established measuring instruments is ensured by regular verification carried out by the CMI or state-authorised metrological centres. An overview of the authorised bodies and the scope of their expertise can be found in here (available in Czech language only).

2. Is there a difference between calibration and verification of a meter? 

Calibration and verification are activities that ensure the correctness of working and specified gauges. The procedure for calibrating working gauges and verifying specified gauges is not fundamentally different, since in both cases the activity involves determining the errors of the gauge at specified points in the measuring range, usually by comparing it with a standard of the relevant quantity.

In the case of calibration, the detected errors can be included in the calibration report of the meter and serve to correct the results of measurements performed by the calibrated meter.

On the other hand, for established gauges, the detected error values are generally not reported as they are not intended to correct the measured values. What is decisive for the verification of the gauge is that the errors of the gauge do not exceed the maximum permissible value, regardless of their distribution. If the specified gauge has the other required metrological characteristics, it shall bear an official mark.

3. What must users of measuring instruments do in cases where the measuring instruments they use are newly included in the generic list of specified measuring instruments? 

In the case where a new type of meter is classified as a specified meter, a number of meters of the relevant type are usually already in use. 

Within 90 days of the entry into force of the relevant legislation, the user is obliged to submit a request for verification of the newly established measuring instruments used by him to the CMI or to the relevant authorised metrology centre. Until the verification procedure is completed, the gauge may be used provisionally.

(§ 26 of Act No. 505/1990 Coll., on Metrology, as amended)

Failure to do so will result in a violation of the law and may expose you to possible penalties.

4. What is an Authorised Metrology Centre and what requirements must an applicant for authorisation meet?    

Authorised metrology centres are entities which have been authorised by the Office to verify specified measuring instruments or certify reference materials on the basis of their application, after verification of the level of their metrological and technical equipment and after verification of the qualifications of the responsible staff.

(§ 16 of Act No. 505/1990 Coll., on Metrology, as amended) 

Requirements for applicants:

(a) is a legal person or a natural person who is an entrepreneur,

(b) it shall be equipped with standards and other equipment necessary for carrying out the relevant technical and administrative tasks,

(c) it has staff competent to act within the scope of the authorisation with appropriate knowledge and skills,

(d) it has no financial or other interests which could influence the results of the metrological activity which is the subject of the authorisation; in the case of authorisation for the post-verification of specified measuring instruments verified at the point of use and also intended for the determination of quantities for direct sale to the public, the authorised body must not be a user, manufacturer, repairer, importer or distributor of those measuring instruments,

(e) has demonstrated metrological, technical and personnel competence to verify specified measuring instruments by submitting the statutory certificates or accreditation certificates.

 (§ 16 of MIT Decree No. 262/2000 Coll., as amended)

Note: You can find the database of authorised entities here (available in Czech language only).

5. What is an official measurement? 

Official measurement, as its name implies, is the ascertainment (measurement) of the value or values of a certain quantity by a body (a legal entity or a natural person who is an entrepreneur) authorised to perform official measurement by the Authority. This authorisation, which is preceded by an appropriate assessment and fulfilment of the requirements set out in Article 13 of Decree No 262/2000 Coll., which ensures the uniformity and accuracy of measuring instruments and measurements, as amended by Decree No 344/2002 Coll., creates the conditions for the authorised body to assume official guarantees for the accuracy of the official measurements made by it. The authorised body shall issue a document on the result of the official measurement, which has the character of a public document within the meaning of Article 21 of Act No 505/1990 Coll., on metrology, as amended.

In general, an "official measurement" is a metrological performance that is certified by an official measurement document. This measurement should therefore primarily serve as a basis or evidence for the actions of courts or administrative authorities and should be understood as such.

The database of bodies authorised to carry out official measurements can be found at here (available in Czech language only).


Provisions of § 134 of Act No. 99/1963 Coll., Civil Procedure Code "Documents issued by the courts of the Czech Republic or by other state authorities within the limits of their jurisdiction, as well as documents declared by special regulations to be public, shall confirm that they are an order or declaration of the authority which issued the document and, unless the contrary is proved, the truth of what is certified or confirmed therein.".

6. What requirements must an applicant for authorisation to perform official measurements meet? 

The requirements for the application and the conditions for authorisation for official measurement are set out in Section 13 of Decree No. 262/2000 Coll., which ensures the uniformity and accuracy of measuring instruments and measurements, as amended by Decree No. 344/2002 Coll.

From the point of view of the professional competence of the applicant for authorisation, it is appropriate to point out the following requirements:

- demonstration of competence to perform official measurements,

- Demonstration of technical and metrological competence (e.g. ensuring metrological continuity of the measuring instruments used, elaboration of procedures for individual types of measurements including their practical knowledge, etc.).

Compliance with these requirements shall be demonstrated by proof of the relevant certificate.

Further information can be obtained from the Metrology Department of the Office.

7. Does the residential water meter need to be checked regularly? 

Meters of the amount of cold and hot water flow (water meters) are, according to Act No. 505/1990 Coll., on Metrology, as amended (hereinafter referred to as "the Act"), established measuring instruments and subject to state metrological control. If the readings of these water meters are used for the allocation of the cost of water consumed, i.e. for one of the purposes referred to in Article 3(3) of the Act, they must be validly verified. This provision also applies to residential water meters whose readings are used for the allocation of the cost of water consumed to individual dwellings. 

For water meters verified until 31.12.2011, the validity period of cold water meters is 6 years and hot water meters 4 years.

With the entry into force of Decree No. 120/2015 Coll., amending Decree No. 345/2002 Coll. of the Ministry of Industry and Trade, i.e. from 1 June 2015, the validity period of the verification of specified measuring instruments listed in item 1.3.9 of the generic list of specified measuring instruments, letter e), is unified to 5 years. This change means that the validity of the verification of all residential cold and hot water meters verified after this date is 5 years. This also applies to domestic hot water meters used for the purpose specified in Decree No 366/2010 Coll.

However, the validity period of the verification of water meters verified before this date shall not change until the next subsequent verification.

8. Are the indicators for the allocation of room heating costs by heating elements meters? 

Within the meaning of Act No. 505/1990 Coll., on Metrology, as amended (hereinafter referred to as the Metrology Act), the indicators for the allocation of room heating costs by heating elements cannot be meters. This statement applies both to electrically powered indicators (EN 258521/EN 834) and to non-powered indicators operating on the principle of liquid evaporation (EN 258522/EN 835). The reason for this is that they are only devices for registering the integrated temperature over time, which do not serve to determine the magnitude of the value of the relevant physical or technical quantity. Therefore, with reference to the above-mentioned Metrology Act, the indicators in question cannot be working measuring instruments and even non-working measuring instruments (Article 3(1) of the Metrology Act). The main reason for this metrological approach to indicators is that their continuity cannot be ensured (Section 5 of the Metrology Act). As far as the relationship of Act No 22/1997 Coll. to indicators is concerned, these are not established products.

The approach to this issue by the EU countries (and indeed all other developed countries) is identical to ours. Also, these countries, as far as we know, do not regard indicators as measuring sticks. To underline this argument, we consider it necessary to point out that the International Organisation for Legal Metrology (OIML, Paris) does not deal with this matter either.

9. What are prepackaged goods (PPG) marked with the symbol "e" and measuring containers marked "3", which regulations apply to them? 

Pre-packaged goods marked with the 'e' symbol are goods intended for sale and placed in packaging without the presence of the consumer, the quantity contained in the packaging, in particular the volume or weight, having a predetermined value which cannot be altered without opening or obvious damage to the packaging.

Packers and importers of pre-packaged goods are entitled to put into circulation goods marked "e" if:

(a) have in place a system of quantity accuracy control ensuring compliance with the requirements set out in the Decree, including a conclusive record of the frequency and results of measurements, notify the CMI in writing of the release into circulation of prepackaged goods marked with the symbol "e" and at the same time provide the CMI with documentation containing the procedures for production control of the quantity of goods in packaging,   

(b) the value of the nominal content and the range of nominal quantities of the contents of prepackaged goods is complied with in the cases provided for in the Decree,

(c) the permitted variations in the contents of the prepackaged goods laid down in the Decree are complied with,

(d) the packaging of prepackaged goods bears the particulars laid down by the Decree. 

Manufacturers of bottles used as measuring containers for prepackaged goods (hereinafter referred to as "bottles") are entitled to mark them with the symbol "3" if:

(a) have a certificate of metrological control of cylinders issued by the CMI, except in the cases provided for in Section 12(1); the manner and methods of metrological control shall be determined by the Ministry by decree,

(b) the permitted variations in bottle volume are respected,

(c) indicate on the bottles the identification marking laid down by Ministerial Decree.

(§ 9a of Act No. 505/1990 Coll., on Metrology, as amended and implementing Decree No. 328/2000 Coll., as amended by Decree No. 404/2008 Coll. and Decree No. 331/2000 Coll.)

Note: Further information can be found on this website under "Technical Harmonisation Proceedings" in the Proceedings "Pre-packaged goods in a nutshell".

10. Is it possible to market spirits in the Czech Republic in ready-made packages of any nominal volume?

Liquor is one of the products that may be placed on the European Union market as prepackaged goods only in nominal quantities as specified in Directive 2007/45/EC laying down rules on nominal quantities for prepackaged products.

In the Czech legal system, this issue is regulated in the provisions of Section 9a of Act No. 505/1990 Coll., on Metrology, as amended, in conjunction with Decree No. 328/2000 Coll., on the method of manufacturing certain types of prepackaged goods whose quantity is expressed in units of weight or volume, as amended. Point 1 of Annex 3 to this Decree sets out the permissible nominal contents volumes for prepackages containing liquid products. For spirits, 9 permissible nominal volumes are laid down, ranging from 100 ml to 2000 ml.

These volumes are (100 - 200 - 350 - 500 - 700 - 1000 - 1500 - 1750 - 2000) ml.

It follows from the above that in the Czech Republic, ready-made packages of spirits in the range of nominal volumes from 100 ml to 2000 ml may be marketed only in the following specified nominal volumes, whether or not they are marked with the symbol "e"

11. Is it possible to put more fuel in the fuel tank than the vehicle documentation states?

The vehicle documentation lists the nominal volume of the fuel tank. The actual volume of the fuel tank is greater than the safety volume of the fuel tank (the volume of the vent chambers and the volume of the filler neck). According to e.g. Škoda Auto a.s., the actual volume of the fuel tank is, depending on the type of vehicle, 10 to 17 litres larger for Škoda vehicles (with a tolerance of approximately +2 to +3 litres). If the nominal volume of the fuel tank is exceeded and the safety space of the fuel tank is thereby filled with fuel, it is possible to draw more fuel than indicated in the vehicle documentation. Filling the fuel tank beyond its rated capacity is not recommended for safety reasons.