CZECH  METROLOGY
INSTITUTE
Okružní 31, 638 00 Brno
legmet@cmi.cz
 +420 545 555 414
P U B L I C  D E C R E E
As the authority with substantive and territorial jurisdiction in the matter of laying down metrological
and technical requirements for legal measuring instruments and laying down the methods for type
approval  and  verification  of  legal  measuring  instruments  under  §  14(1)  of  Act  No 505/1990  on
metrology, as amended (hereinafter the ‘Metrology Act’), and in accordance with the provisions of
§ 172 et seq. of Act No  500/2004, the Code of Administrative Procedure (hereinafter the ‘CAP’), the
Czech Metrology Institute (hereinafter the ‘CMI’) commenced ex officio proceedings on 1. 8.  2023
pursuant to § 46 of the CAP, and, based on supporting documents, issues the following: 
I.
D R A F T  M E A S U R E  O F  A  G E N E R A L  N A T U R E
number: 0111-OOP-C010-23 
stipulating metrological and technical requirements for specified measuring instruments,
including test methods for type approval and verification of specified measuring
instruments:
‘high-speed weigh-in-motion road vehicle scales’
1   Basic definitions 
For the purposes of this measure of a general nature, terms and definitions of the VIM1) and the
following shall apply:
1.1High-speed weigh-in-motion road vehicle scales ( hereinafter ‘scales’): automatic scales that
measure dynamic forces on the tyre of a moving vehicle and detect its presence on a load cell
according to time and calculate the values of the total vehicle mass and axle load or group of axles, or
other vehicle parameters required by a special regulation, directly while the vehicle is in motion and
on its route and for which the requirements of special legislation apply2) 
1.2load cell:  a sensor of the dynamic force exerted by a vehicle tyre on the road 
1.3weighing in entirety:  determining the mass of a vehicle that is entirely on the load plate 
1.4static weighing:  weighing the entire vehicle, load on axles or test load that is static without
movement 
1)   International Vocabulary of Metrology – Basic and general concepts and associated terms (VIM). 
2)   For example, Act No 13/1997 on roads as amended. General Measure No 0111-OOP-C010-23
1.5weigh-in-motion:  a process that uses measurement and analysis of dynamic forces on vehicle
tires to determine the overall load exerted by a moving vehicle and the portions of this load that are
transferred by the wheels or axles of this vehicle 
1.6vehicle mass:  the entire mass of vehicle trailers including all elements permanently connected
to the vehicle or located on it 
1.7axle:  an axle containing two or more wheel assemblies spanning the entire width of the vehicle 
1.8axle group:  a group of two or more axles on the same vehicle, defined by the total number of
axles whose centre points are separated by less than a value specified by special legislation3) 
1.9axle load: the portion of vehicle mass that is exerted via the axle on the load cell during
weighing 
1.10axle group load:  total load on all axles that are part of an axle group 
1.11dynamic force on a tyre:  a force component changing over time applied perpendicular to the
road surface by the tire on a moving vehicle;  in addition to the force of gravity, this force can also
include other dynamic effects on the moving vehicle 
1.12weighing range:  the range between the minimum and maximum value of a measured variable
magnitude, where scales function within the scope of given specifications 
1.13scale interval,  d:  the difference between two consecutive indicated or printed mass values
during weigh-in-motion, expressed in units of mass 
1.14operating speed, v:  the average speed of a moving vehicle as it passes over a load cell, if it is
to be weighed 
1.14.1   maximum operating speed, vmax:  the maximum vehicle speed for which a scale is designed
for weigh-in-motion, and above which it is not guaranteed that the maximum permissible error will not
be exceeded  
1.14.2   minimum operating speed, vmin: the minimum vehicle speed for which a scale is designed for
weigh-in-motion, and below which it is not guaranteed that the maximum permissible error will not be
exceeded  
1.14.3 operating speed range: the speed interval specified by the manufacturer between the minimum
and maximum operating speeds for which the vehicle may be weighed in motion
1.15maximum weighing limit  ( Max):  the maximum  weight  the  load  cell  can measure during
weigh-in-motion 
1.16minimum weighing limit ( Min): the load value below which weigh-in-motion results can be
subject to excessive relative error  
1.17reference scales:  scales used for the static determination of the mass of a reference vehicle and
the load on individual axles of the reference vehicle 
1.18vehicle:  a road vehicle, under load or not, that is recognized by scales as a vehicle that is to be
weighed 
3)   Decree No 209/2018 weights, dimensions and connectivity of vehicles as amended. 
2General Measure No 0111-OOP-C010-23
1.18.1 rigid vehicle: a two-track road vehicle with a single chassis, not including any trailer or semi-
trailer, and with two or more axles located along the length of the chassis
1.18.2 reference vehicle: a vehicle having a known conventional mass determined by reference scales
(both total mass and axle load are considered)
1.19software subject to metrological verification of measuring instruments:  program(s), data
and specific parameters of scale types that belong to a measuring instrument or equipment, and that
define or perform functions that are subject to metrological verification of measuring instruments 
1.19.1  software  parameter  subject  to  metrological  verification  of  measuring  instruments:  a
parameter of software of a measuring instrument or one of its modules that is subject to metrological
verification of measuring instruments
1.19.2 software  identification:  a sequence of legible characters that is a permanent part of the
software (e.g. version number, checksum)
1.20simulated functional test:  a test performed on complete scales or parts thereof, where each
part of the weighing operation is simulated 
1.21weighing zone: a road section consisting of built-in load cells and required minimum lengths of
road sections ahead and behind the load cells   
1.22vehicle  recognition  equipment:  equipment  that  detects  the  presence  of  a  vehicle  in  the
weighing section and whether or when the entire vehicle has been weighed.  The equipment must, by
the nature of the information obtained (together with optical vehicle identification equipment) provide
the prerequisites for subsequent categorisation of vehicles pursuant to special legislation3)  
1.23vehicle speed measurement equipment:  equipment that measures the speed of the weighed
vehicle for the purpose of determining whether the operating speed limit values for which the scales
have been designed or verified have not been exceeded 
1.24indicator:  an electronic device displaying the weighing results in units of mass and other
information, if applicable 
1.25printer:  a device designed to make printed copies of weighing results and other information 
1.26recording equipment:  equipment that records and stores measurement data 
1.27optical  vehicle  identification  equipment:   equipment  intended  for  the  unambiguous
identification of vehicles  that  during  weighing have  been  assessed as exceeding stipulated  mass
parameters 
1.28auxiliary  equipment:   other  equipment  connected  or  connectible  to  the  scales  via
manufacturer-specified interfaces that cannot affect the metrological characteristics of the system 
2   Metrological requirements 
During verification, measuring instruments are subject to the metrological requirements applicable at
the time they were placed on the market or into circulation.
2.1   Rated operating conditions 
2.1.1   Operating temperature range 
Scales must meet metrological requirements at temperatures from -20  °C to +40 °C.
The load cells used and the other sensors situated in the road must fulfil metrological characteristics at
temperatures of at least -20  °C to + 60 °C. 
3General Measure No 0111-OOP-C010-23
For  the  purpose  of  type  approval,  the  manufacturer  may  specify  another  (greater)  operating
temperature range. 
2.1.2   Operating speed  
Scales must meet applicable metrological requirements at vehicle speeds within the stipulated range of
operating speeds. If the actual speed of a vehicle is outside the range of the scales’ operating speeds
during weighing, the scales must (see 3.4): 
–either automatically block the release of the measurement result, or
–indicate or print out the value of the measured actual vehicle speed, and at the same time
indicate or print out a clear warning that the measurement is outside the scales' operating
speed range.
The operating speed must be indicated and/or printed out only after the entire vehicle has been
weighed in motion.
Within the operating speed range specified in the measuring instrument type approval certificate, the
error indicated in the indicated operating speed must not exceed 2  km/h.
2.2   Weighing range 
The manufacturer of the scales specifies the weighing range, which is given by the values Max and
Min , for purposes of type approval and subsequent use. 
The manufacturer must specify the manner in which the scales react when the Max weighing range
value is exceeded and how they indicate this condition. 
2.3   Maximum permissible errors during verification 
2.3.1   Vehicle mass 
The maximum permissible error for vehicle mass determined by weighing in motion is 5  %.
2.3.2   Axle load  
The maximum permissible error for axle load determined by weighing in motion is 11  %.
2.4   Maximum permissible errors in traffic 
2.4.1  Vehicle mass 
The maximum permissible error for vehicle mass determined by weigh-in-motion in traffic is 7  %.
The parameter referred to in Article 3.15.2(e) must not exceed 1.5 times the stipulated value when
using the measuring instrument.
2.4.2   Axle load  
The maximum permissible error for axle load determined by weigh-in-motion in traffic is 15  %.
The parameter referred to in Article 3.15.2(e) must not exceed 1.5 times the stipulated value when
using the measuring instrument.
2.5   Units of measurement 
The units of mass and load used in the equipment are the kilogram (kg) or tonne (t).
2.6   Scale interval  
The scale interval must not exceed the values given in Table 2.
4General Measure No 0111-OOP-C010-23
Table 2 – Scale interval
Axle load 20 kg
Vehicle mass 50 kg
The scale interval of indicator, recording or printing equipments shall be in the form of 1 × 10k, 2 × 10k
or 5 × 10k, where k is a positive or negative integer or zero.
3   Technical requirements 
During  verification,  measuring  instruments  are  subject  to  the  technical  requirements  that  were
applicable when they were placed on the market or into circulation.
3.1   In general 
Scales are an automatic measuring system consisting of the following parts:
–load cells installed on the road;
–vehicle recognition equipment;
–vehicle speed measuring equipment;
–indication equipment;
–printing equipment;
–recording equipment;
–equipment for the optical identification of vehicles;
–auxiliary equipment;
that as a whole is capable of measuring dynamic forces on tyres and detecting the presence of a
moving vehicle on the load cell time, and of calculating total vehicle mass and axle or axle load
values, speed, plus other vehicle parameters required by special legislation3) (e.g. axle separation,
vehicle type).
The scales must be designed so that they are suitable for as great a range of vehicle types utilised for
regular road use as possible.
The scales must be laid out and built in such a way that when they are correctly installed and used in
their intended environment, they maintain their metrological parameters to the extent specified by this
legislation for at least the period for which their verification is valid. 
3.2   Load cell 
A load cell installed in the roadway must detect the presence of a moving vehicle and record the
dynamic forces on the tyres.
3.3   Vehicle recognition equipment 
Scales are intended for operator-free operation, and thus must have vehicle recognition equipment.
The equipment must detect the presence of a vehicle in the weighing zone and must ascertain when the
entire vehicle was weighed.  Given the nature of the information obtained, the equipment must permit
the subsequent categorisation of vehicles in accordance with special legislation4). 
The scales must not indicate, record or print out the mass of the vehicle if all of the vehicle's wheels
were not weighed.
4)   Decree No 153/2023 on vehicle roadworthiness approval and technical conditions of vehicle operation on 
roads.   
5General Measure No 0111-OOP-C010-23
3.4   Vehicle speed measuring equipment  
The speed of a vehicle during weighing must be indicated, and if appropriate recorded and printed out
as part of the vehicle weighing record, in km/h, after being rounded to the nearest whole number.
The scales must not indicate, record or print out the mass or axle or axle group values for any vehicle
that has passed over the load cell at a speed outside the specified range of operating speeds without an
accompanying clear warning signal that these results are not verified.
3.5   Indication equipment 
3.5.1   Indication during normal operation  
Displayed mass and load values must be indicated precisely and unambiguously, and must not lead to
errors. 
Scales are intended for indication of the following values:
–measured values of the total mass, including the unit of measurement;
–measured values of axle or axle group load, including the unit of measurement; 
–the maximum permissible total mass value, including the unit of measurement; 
–the maximum permissible axle or axle group load, including the unit of measurement; 
–the speed of the vehicle being weighed;
–the time (the date, hour, minute and second the measurement was performed), if appropriate.
If scales in a corresponding application are not intended and approved for total mass or axle or axle
group load, the scales can indicate this value for information only, clearly marked that this indication
is not in the verified range of measurement.
3.5.2   Limit indication values 
Scales may indicate, record or print out data on measurement of axle load, axle group load or vehicle
mass, if single-axle load (partial weighing) is lower than Min or greater than Max only if the indication
and/or printed output is accompanied by a clear warning of this problem.
3.6   Printing equipment 
3.6.1   Print output during normal operation 
The printed results must be correct, appropriately identified and unambiguous. Printing must be clear,
legible, indelible and permanent.  
The contents of the printed output are based on the values for which the scales are intended, as
follows:
–the measured value of the total mass, including the unit of measurement;
–the measured value of the axle load(s), including the unit of measurement; 
–the maximum permissible total mass value, including the unit of measurement; 
–the maximum permissible axle or axle group load, including the unit of measurement; 
–time (resolution to the second) and date (day, month, year);
–the speed of the vehicle being weighed;
–the type of scales (e.g., an abbreviation).
If scales in a corresponding application are not intended and approved for total mass or axle or axle
group load, the scales can indicate this value for information only, clearly marked that this indication
is not in the verified range of measurement.
6General Measure No 0111-OOP-C010-23
3.6.2    Agreement between indication and printing equipment 
For the same load, there must not be any difference between the indicated and printed weighing result,
if the indication and printing equipment have the same scale interval.
3.7   Recording equipment 
3.7.1   Scope of recorded data 
The recording equipment must record and store all relevant measurement data. The minimum scope of
data recorded and stored by this equipment is the same as the contents of printed output pursuant to
article 3.6.1. 
3.7.2   Data memory 
Data may be stored in the scales' memory (e.g. on a hard disk) or in external storage for subsequent
operations  (indication,  printing,  transmission,  summation,  etc.).  Stored  data  must  be  reasonably
protected against intentional and unintentional changes during the transmission and/or storage process,
and must contain all relevant information needed to reconstruct past measurements. 
The following requirements apply to the security of stored data:
a)relevant security requirements in Article 3.14;
b)the  software  transmission  and  download  process  must  be  secured  in  accordance  with
requirements in Article 3.14;
c)external memory identification and security attributes must ensure integrity and authenticity;
d)exchangeable storage media for storing measurement data need not be sealed, providing that
stored data is secured by a specific checksum or key code;
e)if the memory capacity is exhausted, data may be overwritten by new data using a code key or
in another way compatible with the above requirements.
3.8   Optical vehicle identification equipment 
Scales  must  be  equipped  with  a  device  pursuant  to  Article  3.8.1  or  3.8.2  for  the  unambiguous
identification of those vehicles that during weighing were found to exceed specified mass parameters.
This identification must meet security, integrity and authenticity requirements.  
3.8.1   Imaging unit 
Scales may be equipped with a digital camera that captures the weighing situation with dependable
identification of the weighed vehicle, which is displayed on a connected remote display along with the
following values measured by the scales:
–measured values of total mass, including the unit of measurement;
–measured values of axle or axle group load, including the unit of measurement.
3.8.2   Image recording unit 
Scales must be equipped with an image recording unit that must capture the situation during weighing,
ensuring identification of the vehicle being weighed.
An image-recording unit working in automatic mode may enable the setting of a limit mass for image
recording.
The situation on the scales is recorded by a digital camera, which outputs individual digital images or
video sequences stored in digital memory.
The following must be displayed on individual images or in video sequences in the data display field: 
–measured values of total mass, including the unit of measurement;
7General Measure No 0111-OOP-C010-23
–measured value of axle load, including the unit of measurement; 
–time (resolution to the second) and date (day, month, year);
–the type of scales (e.g., an abbreviation). 
If the above data is displayed only on the main image, the other images must be marked with a unique
identifier that ensures the integrity, authenticity and unambiguous identification of the images and
associated data. The image identifier must be generated using a cryptographically strong algorithm or
digital  signature  and  shall  contain  information  on  the  exact  time  the  image  was  taken  and  the
equipment that carried out the weighing and its geolocation. 
For digital images, image information and information regarding measured values must be inseparably
joined into one data file. This information must also be integrated into the pixel structure of the digital
image.  To ensure integrity, the digital image data file must have a digital mark (signature).  The origin
(authenticity) of the entire digital image data file must be uniquely identifiable (e.g. the ID number of
the scales).  
Video sequences to be archived must have their integrity (integrity) and origin (authenticity) ensured
in order to avoid undue changes in the content of images and measured data or incorrect assignments.
3.9   Auxiliary equipment 
Any external equipment connected to the scales via an appropriate interface must not have a negative
influence on their metrological parameters. 
3.10   Resistance to external influences 
Disruptive external influences on the scales must not lead to measurement errors that would exceed
the scales' greatest permissible error according to Articles 2.3.1 or 2.3.2.
3.10.1   Physical durability 
The design of the scales and materials used must guarantee sufficient rigidity, stability and resistance
to mechanical vibrations and shocks. The manufacturer must specify the physical conditions in which
the scales should be used.  For the load cell, a physical environment class with high or very high level
of vibrations and shocks applies, designated as M3 pursuant to special legislation5)). 
3.10.2   Weather resistance 
In its off state, a load cell installed in a roadway must be able to withstand temperatures between -
40 °C and +70 °C without  damage, and after  returning to  its  operating temperature  range, must
function within the range of maximum permissible error.
To  ensure  correct  measurement  in  relation  to  ambient  temperature  and  the  scales'  operating
temperature range, the scales must have a temperature measurement device. The scales must be
capable  of  automatically  recognizing  a  temperature  outside  the  operating  temperature  range  and
displaying a suitable warning.  Any weighing taking place at that moment must be terminated and the
scales must block further weighing or switch themselves off. 
The scales must not be sensitive to ambient relative humidity.
3.10.3   Resistance to dust and water 
Those portions of the scales that are subject to the effects of weather must have at least an IP 67
housing to provide protection from dust and temporary immersion in water, and other parts at least IP
54.
5)   Government Regulation No 120/2016 on conformity assessment of measuring instruments when made 
available on the market , as amended, implementing Directive 2014/32/EU of the European Parliament 
and of the Council of 26 February 2016 on the harmonisation of the laws of the Member States relating 
to the making available on the market of measuring instruments . 
8General Measure No 0111-OOP-C010-23
3.10.4   Electromagnetic compatibility (EMC) 
The scales must not be influenced by electrical or electromagnetic interference, or must react to it in a
defined manner (e.g. reporting an error, blocking measurement, etc.). They must also not radiate any
unwanted electromagnetic fields. 
During laboratory EMC tests, the scales or parts thereof must exhibit normal function and the results
of simulated functional tests must be within the limits of greatest permissible error pursuant to Articles
2.3.1 or 2.3.2.
3.11   Power 
Scales powered from the electrical grid must meet metrological requirements under normal voltage
fluctuation conditions. If voltage declines below the minimum operating voltage, the scales must be
blocked  from  working  or  their  activity  outside  specified  operating  conditions  must  be  clearly
indicated, for example by a suitable warning.  
3.12   Measuring instrument security and fraud protection 
Scales must not have characteristics that would facilitate fraudulent use, and there must be a minimum
of ways in which they can be unintentionally improperly used. Components that are not intended to be
disassembled or adjusted by the user must be protected from such activity. 
3.13   Software 
3.13.1   Software subject to metrological verification of measuring instruments 
The software used in scales must be presented in such a form that software cannot be changed without
damaging a seal, or each change in software can be automatically recorded and its nature specified
with the use of an ID code. 
The software documentation for scales must include:
a)a description of the software subject to metrological verification of measuring instruments;
b)a description of measurement algorithm accuracy (e.g. programming modes);
c)a description of the user interface, menus and dialogues;
d)unique identification of the software;
e)a description of included software (e.g. operating environment);
f)a hardware system overview, e.g. a topological block diagram, type of computer(s), source
code for software functions, etc., if not described in the user manual;
g)software security resources;
h)a user manual.
3.13.2   Software security resources 
Resources for securing software subject to metrological verification of measuring instruments are as
follows:
a)only authorized individuals may be given access, for example using codes (passwords) or a
special device (hardware key, etc.); codes must be changeable; 
b)the measuring instrument's memory must store all accesses, listing the date of the access,
identification of the authorized individual performing the access, and the type of access;
c)memory capacity must be sufficient for at least 2 years of expected accesses; if memory
capacity for access record storage is exhausted, no automatic erasure of any stored records can
take place; 
9General Measure No 0111-OOP-C010-23
d)it must be possible to recall relevant access records to the full extent of information recorded;
e)it must not be possible to erase access records without removing a physical seal;
f)downloading of software subject to metrological verification must be possible only via an
appropriate secure interface connected to the scales;
g)the software must include identification of its version, which must change if any software
version changes occur;
h)functions that are performed or launched via a software interface must meet the terms and
conditions of this legislation.
3.14   Hardware and software security 
3.14.1   In general 
All scale equipment including software, which is intentionally to be prevented from disconnection or
removal by a user or other individual, must be equipped with a housing or other suitable means of
security. It must be possible to seal housings after their closure;  sealing points must be easy to access
in all instances.  All parts of the measuring system that cannot be protected by housings must be
equipped with sufficiently effective means of preventing operations that tend to influence measuring
accuracy. 
Each  piece  of  scale  equipment  that  could  influence  measuring  results,  especially  equipment  for
calibration and adjustment of scales or for correction of measured values, must be sealed.
3.14.2   Means of security 
Security must consist of sealed housings, encryption, passwords or similar software means in such as
way that:
a)the software security requirements in Article 3.13.2 apply;
b)transmission of measurement results data via an interface must be protected from intentional,
unintentional and random changes;
c)the  scales  must  be  secured  in  such  a  way  to  make  it  possible  to  secure  scale  settings
separately;
d)stored data must be protected from intentional, unintentional and random changes.
3.15   Installation of scales 
3.15.1   In general 
Scales must be installed to minimise any adverse effects of the installation environment on measuring
accuracy  and  related  data.  The  scales  shall  preferably  be  installed  outside  areas  where  frequent
acceleration or deceleration could occur and must not be installed in sections where the number of
lanes changes. 
All installation requirements that have an effect on the weighing operation must be stipulated in
sufficient detail. The manufacturer of the scales shall, if necessary in relation to the basic requirements
of Articles 3.15.2 and 3.15.3 and to ensure correct weighing of vehicles, stipulate more detailed
specifications  for  installation  requirements.   Those  closer  requirements  shall  be  included  in  the
measuring instrument type approval certificate.    
Where  relevant,  other  conditions  or  recommendations  for  the  installation  of  scales  providing
conditions for ensuring adequate long-term stability of their metrological characteristics (e.g. more
detailed requirements for the qualitative characteristics of the road within the weighing zone) shall be
indicated by the manufacturer in the technical documentation of the specified measuring instrument or
in the installation or operating instructions of the given type of scales.  
10General Measure No 0111-OOP-C010-23
3.15.2   Roadway geometry 
The section of roadway at least 75  m in front of and 25 m past the load cell must meet the following
requirements:
a)the road gradient must be  1 %;
b)the road's cross slope must be  3 %;
c)the radius of curvature of the road's longitudinal axis must be  1000 m;
d)the road must be free of irregularities causing local gradient changes;
e)the depth of ruts must not be greater than 4 mm.
For the purpose of type approval, other criteria for roadway geometry specified under points (a) to (c)
specified by the manufacturer are also permitted if the applicant for type-approval demonstrates by
means of sufficiently representative evidence (in particular the results of tests of installed weights of a
given  or  structurally  related  type)  that,  even  under  these  conditions,  the  scales  meet  the  other
requirements pursuant to this measure, in particular the requirements for the maximum permissible
errors pursuant to Article 2.3 or 2.4 (see Article 5.4.6.3). The different conditions must be specified in
the type approval certificate.  
3.15.3   Roadway characteristics 
The roadway in the load cell installation location must meet the following requirements:
–below the roadway's top layer, there must be a standard substrate without reinforced locations
(e.g. without special facilities such as service shafts, etc.);
–load cells must be installed in homogeneous layers where the surface is undamaged;
–along the entire span of load cells, the roadway must be homogeneous across each traffic lane
and without masonry joints;
–the scales' load cells must not be installed in locations where undesirable dynamic effects
could occur, such as on bridges.
4   Measuring instrument markings 
During  verification,  measuring  instruments  are  subject  to  the  marking  requirements  that  were
applicable when they were placed on the market or into circulation.
4.1   Markings on measuring instruments 
Scales must bear the following markings:
–the manufacturer’s identification mark;
–identification of the type of scales;
–the serial number of the scales; 
–if scales are not suited or intended for weighing vehicles that have specific characteristics (e.g.
axle suspension design, number of axles) or transporting loads with specific characteristics
(e.g. liquids), they must be marked with a notice or this restriction on suitability for weighing
with a clear specification of the type and scope of this restriction (if relevant for the scales in
question);
–the direction of weighing (if applicable for the scales);
–power supply voltage, in V;
–power supply frequency, in Hz;
11General Measure No 0111-OOP-C010-23
–operating temperature range (if different from the minimum requirements pursuant to Article
2.1.1), in °C;
–identification of the software (if appropriate);
and the following information on metrological parameters:
–upper weighing limit Max =....., in kg or t;
–lower weighing limit Min =....., in kg or t;
–scale interval d =....., in kg or t;
–maximum operating speed Vmax =....., in km/h;
–minimum operating speed Vmin =....., in km/h;
–maximum number of axles per vehicle (if applicable) Amax;
–type approval mark in accordance with national requirements.
4.2   Presentation of markings 
The markings pursuant to Article 4.1 must be legible, unambiguous and intelligible and indelible
under the scales' normal conditions of use.
These markings may be either in the Czech language or in the form of adequate internationally agreed
and published symbols or signs.
Markings must be grouped together in a clearly visible place on the scales on the indicating device in
its immediate vicinity or on an easily accessible, clearly visible non-removable part of the scales. If the
markings are not a fixed part of a non-removable part of the scales, they must be secured with an
official mark. 
4.3 Official marks
Scales and components thereof must permit the placement of an official mark or marks so that:
–scale components on which marks are placed cannot be removed from the scales without 
damaging the marks;
–the marks can be placed without changing the metrological characteristics of the scales;
–they are visible on the scales during normal installation.
5   Measuring instrument type approval 
The following are performed during type approval:
–external inspection;
–tests of the scales' resistance to disruptive environmental effects;
–functional weigh-in-motion tests on location during road traffic.
5.1   External inspection 
During an external inspection of scales, the following are assessed:
a)that prescribed technical documentation is complete, including a user manual;
b)that metrological and technical characteristics specified by the manufacturer in documentation 
comply with the requirements of this legislation specified in chapter 2 and 3;
c)that functional wholes are complete and comply with prescribed technical documentation;
d)that the scales' software version agrees with the version specified by the manufacturer.
12General Measure No 0111-OOP-C010-23
5.2   Simulated functional tests in the laboratory 
Simulated functional tests are performed when assessing resistance to the influence of the external
environment according to 5.3, on complete scales unless the size and/or configuration of the scales
makes it impossible to test them in their complete form. In such cases, testing is allowed with a load
signal generator taking the place of load cells. 
The metrological body approving measuring device types can accept a manufacturer's proposal to
modify the method and manner in which simulated functional tests are performed, if suitable with
regards to the specifics of the technology and design of the scales' measurement chain.
5.3   Tests of resistance to the influence of the external environment 
5.3.1   Tests of resistance of scales to physical effects 
5.3.1.1   Test of the resistance of scales to random vibrations 
Resistance to random physical vibrations is tested on scales in their on state by applying vibrations
with the following parameters:
–frequency range: 10  Hz to 150 Hz; 
–overall effective acceleration level: 7  m/s2, 
–spectral density of acceleration 10  Hz to 20 Hz: 1 m2/s3; 
–spectral density of acceleration 20  Hz to 150 Hz: -3 dB/octave; 
in all three axes, always for 2 minutes.
During  this  test  the  tested  scales  must  remain  functional,  and  during  the  subsequent  simulated
functional test, measurement error must not exceed the maximum permissible error listed in Article
2.3.1 or 2.3.2.
5.3.1.2   Impact resistance test 
Impact  resistance  is  tested  with  the  scales  switched  on,  by  applying  repeated  impacts  with  the
following parameters:
–peak acceleration: 100  m/s2; 
–duration of rated impulse: 16 ms; 
–corresponding change in velocity;  1 m/s; 
–number of impacts in each direction: 1000 ±  10. 
During  this  test  the  tested  scales  must  remain  functional,  and  during  the  subsequent  simulated
functional test, measurement error must not exceed the maximum permissible error listed in Article
2.3.1 or 2.3.2.
5.3.2   Weather resistance tests 
5.3.2.1   Test of resistance to limit temperatures 
Resistance to limit ambient temperatures pursuant to Article 3.10.2 is tested with the scales switched
off:
a)with dry heat at 70 °C for 2 h;
b)with cold at -40 °C for 2 h.
Following this test, the scales must not exhibit any damage, and during the following simulated
functional test, measurement error must not exceed the maximum permissible error listed in Article
2.3.1 or 2.3.2.
13General Measure No 0111-OOP-C010-23
5.3.2.2   Resistance to operating temperatures 
Resistance  to  operating  ambient  temperatures  pursuant  to  Article  2.1.1  is  tested  with  the  scales
switched on:
a)with dry heat at the upper limit of the ambient operating temperature range for 2 h;
b)with cold at the lower limit of the ambient operating temperature range for 2 h.
During this test the scales must function normally, and the error during a simulated functional test
must not exceed the maximum permissible error listed in Article 2.3.1 or 2.3.2.
5.3.2.3   Resistance to air humidity 
Resistance to air humidity pursuant to Article 2.2 is tested with the scales switched on with two 24-
hour cycles of moist heat with a maximum temperature of 40  °C.
During  this  test  the  tested  scales  must  remain  functional,  and  during  the  subsequent  simulated
functional test, measurement error must not exceed the maximum permissible error listed in Article
2.3.1 or 2.3.2.
5.3.2.4   Dust and water resistance 
Dust and water resistance pursuant to Article 3.10.3 is tested in the off state on those parts of the
scales that are exposed to the effects of weather.
Following this test, the scales must not exhibit any damage, and during the following simulated
functional test, measurement error must not exceed the maximum permissible error listed in Article
2.3.1 or 2.3.2.
5.3.3   Electromagnetic compatibility (EMC) tests 
5.3.3.1   Immunity to conducted disturbances induced by radio-frequency fields 
Immunity  to  conducted  disturbances  induced  by  high-frequency  fields  is  tested  with  the  scales
switched on, over a 150 kHz to 80 MHz frequency range with a test field amplitude of 10 V. The
interference is applied to signal cabling longer than 3 m, at all DC power inputs and outputs, at all AC
power inputs and outputs, and at all functional ground connections.
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.3.2   Immunity to radiated radio-frequency electromagnetic fields  
Immunity to radiated high-frequency electromagnetic fields is tested with the scales switched on, in
the 80 MHz to 2 GHz frequency range with test field intensity amplitude of 10 V/m and 80  %
amplitude modulation with a 1 kHz sinus wave. The interference is applied to all sides of the scales'
housing. 
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.3.3   Immunity to electrostatic discharge 
Immunity to electrostatic discharge is tested with the scales switched on, preferably with a contact
discharge of 6 kV or with an 8 kV air discharge. Discharges are applied to the scales' housing and to
coupling plates near the scales. 
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
14General Measure No 0111-OOP-C010-23
5.3.3.4   Immunity to electrical fast transient/burst disturbances 
Immunity to electrical fast transients/bursts is tested with the scales switched on at a no-load test
voltage of ± 1 kV for at least 1 minute on signal terminals with a repeat frequency of 5 kHz. The
interference is applied to signal cabling longer than 3 m, at all AC power inputs and outputs, and at all
functional ground connections longer than 3 m. 
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.3.5   Immunity to surges 
Immunity to surges is tested with the scales switched on by applying a surge of:
–± 1 kV line to ground; to signal lines longer than 30  m; 
–± 0.5 kV line to line and a symmetrical test voltage of ±  0,5 kV on DC power lines longer than
10 m.
Interference is applied to signal lines longer than 30 m or to lines partly or entirely installed outdoors,
regardless of their length.
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.3.6   Immunity to power-frequency magnetic fields  
Immunity to 50 Hz magnetic fields is tested with the scales switched on with a continuous magnetic
field of intensity 30 A/m on the equipment housing.
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.3.7   Immunity to AC mains voltage dips  
Immunity to short AC mains voltage dips, short interruptions and slow voltage variations is tested with
the scales switched on at all AC power inputs with a supply current of < 16 A by applying a voltage
reduction: 
–of 40 % of UN for 10 AC voltage cycles; 
–of 70 % of UN for 25 AC voltage cycles; 
–of 80 % of UN for 250 AC voltage cycles; 
where UN is the nominal value of AC mains voltage.
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
5.3.4   Test of immunity to supply voltage limit values 
Immunity to supply voltage limit values is tested with electronic devices switched on. For AC, its
limits are given as Unom — 15 % and Unom + 10 %, where Unom is the rated supply voltage. 
During a simulated functional test under the given test conditions, measurement error must not exceed
the maximum permissible error listed in Article 2.3.1 or 2.3.2., or the system must detect a serious
error and react to it.
15General Measure No 0111-OOP-C010-23
5.4   Weigh-in-motion accuracy road tests 
5.4.1   In general 
Complete scales installed pursuant to Article 3.15 are subjected to weigh-in-motion accuracy tests.
5.4.2   Test equipment 
5.4.2.1   Reference vehicles 
The reference vehicles used in weigh-in-motion tests must represent the range of use of the scales
specified by their manufacturer for the purpose of type approval. Reference vehicles are intended to
represent different vehicle designs, axle configurations, connection and suspension systems.  
At least the following reference vehicles shall be used:
–a rigid two-axle vehicle;  
–a rigid three-axle or four-axle truck; 
–a tractor with a semi-trailer with a minimum of three axles;  
–a rigid truck with a trailer with two or three axles.
If the scales are to be used to determine vehicle mass or single-axle or axle group loads for vehicles
transporting loads whose centre of gravity can shift during vehicle motion, reference vehicles must
include those carrying loads in the form of liquids or other products that can change the position of
their centre of gravity during vehicle motion.
5.4.2.2   Reference vehicle loading 
The combination of the reference vehicles used and their chosen load must represent the measuring
range of the instruments specified by their manufacturer for the purpose of type approval.
Vehicle loads shall be selected in such a way that the maximum permitted values of the total mass of
the vehicles and the maximum permitted values of the axle(s) are not exceeded, pursuant to a special
legislation3).  
5.4.2.3   Reference scales 
During testing, standalone reference scales must be available to determine the conventional true mass
value of each vehicle and the reference single-axle or axle group load. 
5.4.2.3.1   Reference scales for measuring reference vehicle mass 
To determine the conventional overall mass value of reference vehicles, preference is given to stand-
alone reference scales that can determine the conventional mass value of each reference vehicle by
weighing it all at once with an error less than or equal to one third of the applicable MPE for weigh-in-
motion pursuant to Article 2.3.1. 
5.4.2.3.2   Reference scales for measuring reference axle load of a reference vehicle 
To determine the conventional axle load, stand-alone portable reference scales for weighing Class III
or IV vehicles are used, or low-speed scales of accuracy class 1 or better.
5.4.3   Test conditions 
Tests  are  performed  under  operating  conditions  stipulated  by  the  manufacturer  of  the  scales  in
question.
16General Measure No 0111-OOP-C010-23
5.4.4   Determining reference values for reference vehicles 
5.4.4.1   Conventional true value of the reference vehicle mass 
The conventional true mass value for each reference vehicle, unloaded and loaded, must be determined
by static full-draught weighing on reference scales (see Article 5.4.2.3.1). 
5.4.4.2   Conventional true value of the axle load of a reference vehicle 
Reference scales are used to determine conventional axle load values for an unloaded and loaded
reference vehicle (see Article 5.4.2.3.2).
The reference scales are used to sequentially determine the load on each axle of the reference vehicle,
with at least three to five test runs in both directions. The mean reference axle load is calculated as the
arithmetic average of recorded values.  
To correct for the influence of the method used, the total vehicle mass is calculated by axles as the
sum of mean load values on individual axles VM.
The corrected mean reference load value per axle is then:
(1)
where: VMrefis the conventional value of each reference vehicle mass determined by full-
draught weighing pursuant to Article 6.2.2.1. 
To verify that reference axle loads are correct, the following must apply:
The corrected mean load value (see above) is used as the conventional per-axle load of the reference
vehicle.
5.4.5   Verification of scales installation at the weighing location 
Road geometry is checked pursuant to Article 3.15.2, and must meet all criteria.
5.4.6   Weigh-in-motion reference vehicle tests 
5.4.6.1   Test runs 
Each reference vehicle must perform at least ten test runs at each of the three following speeds:
a)near the maximum operating speed, Vmax;
b)near the minimum operating speed, Vmin;
c)near the middle of the operating speed range;
(each reference vehicle must thus perform a total of 30 test runs).
For every ten test runs at a given test speed, the vehicle must be positioned above the centre of the
load cell six times, twice on the left and twice on the right side of the load cell. 
5.4.6.2   Test run speed 
Vehicle speed must be kept as constant as possible during each test run. The scales must indicate and
record the speed of the tested vehicle as it passes over the load cells. 
17General Measure No 0111-OOP-C010-23
5.4.6.3   Weigh-in-motion accuracy test 
During weigh-in-motion accuracy tests, all test runs are performed pursuant to 5.4.6.1 using reference
vehicles pursuant to 5.4.2.1. The values of all vehicle mass indications and all axle load indications are
recorded.  For each recorded value (total vehicle mass, axle or axle group load), the relative error δ is
calculated in percent: 
(2)
where:Cis the value measured by the scales; 
R is the corresponding reference value measured by the reference scales.
The number of relative errors  δ that exceed the stipulated maximum permissible error pursuant to
Article 2.3.2 for each quantity is determined, and this number is expressed as the relative number of
values for each quantity as follows:
(3)
where: N is the number of calculated differences exceeding the maximum permissible error;
N is the total number of recorded values for the given quantity.
The number of relative errors exceeding the maximum permissible error Pde must not be greater than
5 %, and these errors must not be greater than the maximum permissible error for traffic (see Article
2.4.2).  
5.4.7   Operating speed tests  
5.4.7.1   Operating speed blocking test  
During the operating speed blocking test, a test run by one reference vehicle must take place at a speed
outside the operating speed range, as follows:
a)at a speed at least 5 % higher than the maximum operating speed, Vmax;
b)at a speed at least 5 % lower than the minimum operating speed, vmin, (if the scales can be used
for this).
The scales must detect the above conditions and must react in accordance with Article 3.4.
5.4.7.2   Operating speed test 
To determine and test operating speed during a weigh-in-motion test, six test runs shall take place with
an unloaded two-axle rigid reference vehicle across load receptors at a constant speed. Three runs
must take place near the maximum operating speed vmax, and three additional runs must take place at
exactly the listed minimum operating speed vmin. 
A reference speedometer shall be used to determine the reference speed. For each speed measurement,
the error of the indicated operating speed shall be calculated.  The indicated operating speed error
must not exceed the error given in Article 2.1.2. 
6   Initial verification 
6.1   In general  
The following is performed during initial verification of scales:
a)a visual inspection;
b)functional weigh-in-motion tests in road traffic;
18General Measure No 0111-OOP-C010-23
c)operating speed tests.
6.2   Visual inspection 
The following is assessed during a visual inspection of scales submitted for verification:
a)conformance of the scales with the approved type;
b)completeness and condition of the scales' functional wholes;
c)that the software version an approved one.
6.3   Functional weigh-in-motion tests in road traffic 
6.3.1   Reference vehicles and their loading 
During weigh-in-motion functional tests in road traffic, reference vehicles and their loading must, for
purposes of initial verification, represent the measuring range and range of application specified by the
type approval certificate or the limited measuring range of the instrument and the range of use
specified by their user for the specific installation site. 
Vehicle loads shall be selected in such a way that the maximum permitted values of the total mass of
the vehicles and the maximum permitted values of the axle(s) are not exceeded, pursuant to a special
legislation3).  
At least the following reference vehicles shall be used:
–a rigid two-axle vehicle;
–a rigid three-axle or four-axle truck;
–a tractor with a semi-trailer with at least three axles or a rigid truck with a trailer with two or 
three axles.
Only reference vehicles carrying loads in the form of stable loads whose centre of gravity cannot
change its position when the vehicle is moving shall be used for verification. 
6.3.2   Test runs 
Each reference vehicle must perform at least ten test runs at the site where the scales are installed, in
each lane, at each of the three following speeds:
a)near the maximum operating speed, Vmax;
b)near the minimum operating speed, Vmin.
For every ten test runs at a given test speed, the vehicle must be positioned above the centre of the
load cell six times, twice on the left and twice on the right side of the load cell. 
Vehicle speed must be kept as constant as possible during each test run. 
6.3.3   Weigh-in-motion accuracy tests in road traffic 
When testing accuracy by weigh-in-motion in road traffic, the test runs pursuant to Article 6.3.2 shall
be carried with reference vehicles pursuant to Article 6.3.1. The values of all vehicle mass indications
and all axle load indications are recorded.  The test shall be evaluated in accordance with Article
5.4.6.3. 
6.4   Operating speed tests 
During initial verification, operating speed tests in accordance with Article 5.4.7.1 are performed.
19General Measure No 0111-OOP-C010-23
7   Subsequent verification 
During verification, measuring instruments are subject to the requirements that were applicable when
they were placed on the market or into circulation.
7.1   In general  
During subsequent verification of scales, the following are performed:
a)a visual inspection;
b)functional weigh-in-motion tests in road traffic;
c)operating speed tests pursuant to Article 5.4.7.1 (only if the minimum or maximum operating 
speed values have changed compared to the previous verification of the scales).
7.2   Visual inspection 
Visual inspection during subsequent verification proceeds in accordance with Article 6.2.
7.3   Functional weigh-in-motion tests in road traffic 
Functional weigh-in-motion tests in road traffic are performed at the site where the scales are installed
pursuant to Article 6.3.
7.4   Operating speed tests 
Operating speed tests are performed pursuant to Article 5.4.7.1, and only if the minimum or maximum
operating speed values have changed compared to the previous verification of the scales.
8   Shortened test 
If legislation6) stipulates the performance of short tests confirming the validity of the verification at the
time of use of the measuring instrument, the accuracy of the scales shall be tested by means of weigh-
in-motion in road traffic at the site where the scales are installed pursuant to Article 6.3, and the scope
of the test is focused on evaluating the total mass under one load of the reference vehicle used, where
the number of runs must not be less than eight. 
The greatest permissible errors shall be the greatest operating errors in traffic pursuant to Article 2.4.
9   Measuring instrument examination 
When examining measuring instruments pursuant to §  11a of the Metrology Act at the request of a
person who may be affected by an incorrect measurement, proceed according to Chapter  7. The test is
always performed if it is technically possible.  
The greatest permissible errors shall be the greatest operating errors in traffic pursuant to Article 2.4.
10   Notified standards 
For the purposes of specifying the metrological and technical requirements for measuring instruments
and specifying the testing methods for their type approval and verification arising from this General
Measure,  the  CMI  shall  notify  Czech  technical  standards,  other  technical  standards  or  technical
documents of international or foreign organisations, or other technical documents containing more
detailed technical requirements (hereinafter ‘notified standards’). The CMI shall publish a list of these
notified standards attached to the relevant measures, together with the general measure, in a manner
accessible to the public (at www.cmi.cz). 
6)   Decree No 345/2002 stipulating measuring instruments for mandatory verification and measuring 
instruments subject to type approval. 
20General Measure No 0111-OOP-C010-23
Compliance  with  notified  standards  or  parts  thereof  is  considered,  to  the  extent  and  under  the
conditions laid down in the general measure, as compliance with those requirements laid down in this
measure to which these standards or parts thereof apply.
II.
G R O U N D S
The CMI has issued this General Measure laying down metrological and technical requirements for
specified measuring instruments and tests for the type approval and verification of these specified
measuring instrument in accordance with §  14(1)(j) of the Metrology Act to implement §  6(1), § 9(1)
and § 9(9) of the Metrology Act.
Decree No 345/2002 stipulating measuring instruments for mandatory verification and measuring
instruments subject to type approval, as amended, classifies high-speed weigh-in-motion road vehicle
scales  as  measuring  instruments  subject  to  type  approval and mandatory verification under item
2.1.3(c) in the Annex ‘List of Specified Measuring Device Types’.
As such, the CMI has issued this Measure of a General Nature to implement §  6(1), § 9(1), § 9(9),
and § 11a(3) of the Metrology Act for this specific type of measuring instrument, ‘high-speed weigh-
in-motion road vehicle scales’, laying down metrological and technical requirements for high-speed
weigh-in-motion road vehicle scales and tests for the type approval and verification of these specified
measuring instruments.
This  legislation  (Measure  of  a  General  Nature)  was  notified  in  accordance  with  Directive
(EU) 2015/1535 of the European Parliament and of the Council of 9  September 2015 laying down a
procedure  for  the  provision  of  information  in  the  field  of  technical  regulations  and  of  rules  on
Information Society services.
III.
I N S T R U C T I O N S
In accordance with §  173(2) CAP, no remedy may be submitted against a measure of a general nature.
In accordance with the provisions of §  172(5) CAP, no appeal or remonstrance may be filed against
the decision on objections.
Compliance of a general measure with legal regulations may be assessed in a review procedure
pursuant to § 94 to § 96 CAP.  A party to the proceedings may initiate review proceedings to be
conducted  by  the  administrative  authority  that  issued  the  measure  of  a  general  nature.   If  the
administrative authority finds no reason to commence the review proceedings, it shall communicate
and  provide  grounds for  this  within  30  days.  Pursuant  to Article  174(2) CAP   a ruling  on  the
commencement of review proceedings can be issued within three years of the effective date of the
measure of a general nature. 
IV.
E F F E C T I V E  D A T E  A N D  R E P E A L I N G  P R O V I S I O N S
This measure of a general nature takes effect on the fifteenth day after its date of publication (§  24d of
the Metrology Act).
Measure  of  a  General  Nature  number:  0111-OOP-C010-15,  laying  down  the  metrological  and
technical requirements for specified measuring instruments, including testing methods for verification
of the following specified measuring instruments:  ‘high-speed weigh-in-motion road vehicle scales’ is
repealed.  
21General Measure No 0111-OOP-C010-23
doc. RNDr.  Jiří Tesař, Ph.D. v. r. 
Director General
 Czech Metrology Institute 
22