Czech Metrology Institute  
Okružní 31, 638 00 Brno  
 
1 
1. ------IND- 2018 0333 CZ - EN- ------ 20180803 --- --- PROJET 
Executive summary for the EC (not part of this legislation)  
Grain testers for determining the bulk density of cereals, oilseeds  and pulses are placed on the 
market and put into use in the Czech Republic as specified measuring instruments following type 
approval and initial validation pursuant to Act  No 505/1990 on metrology, as amended.  
The subject of this notified regulat ion is to lay down metrological and technical requirements for 
these measuring instruments.This regulation also stipulates tests for type approval and verification.  
(End of executive summary.)  
 
 
Contact person:Mgr.Tomáš Hendrych  
Phone: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 a specified measuring instrument and determining test methods for type 
approval and verification of the specifie d measuring instrument pursuant to §  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 
14 June2016 pursuant to §  46 of the CAP, and, based on supporting documents, issues the following:  
 
I. 
D R A F T  G E N E R A L  M E A S U R E 
number:0111 -OOP -C058 -16 
stipulating metrological and technical requirements for specified measuring 
instruments 'grain testers'  
and test methods for type approval and verification of these specified measu ring 
instruments  
1 Basic definitions  
For the purposes of this general measure, the terms and definitions according to VIM and VIML1 and 
the following apply:  
                                                      
1 TNI 01 0115 International Vocabulary of Metrology —Basic and General Concepts and Associated Terms 
(VIM) and International Vocabulary of Legal Metrology (VIML) are part of the technical harmonisation 
compendium ‘Terminology in the field of metrology’, which is publicly available at www.unmz.cz.  Measure of a General Nature No  0111 -OOP -C058 -16 
2 1.1 
grain tester  
a mechanical or electrical, manual or automatic device for measuring the volume of  grain under 
specific conditions in order to determine the 'mass per hectolitre' of cereals, oilseeds  and pulses; the 
device must be verified pursuant to this Measure of a General Nature (hereinafter the 'Measure') and 
must comply with its requirements.  
A grain tester determines the hectolitre weight of cereals, oilseeds  and pulses in ranges stipulated by 
the manufacturer or in the measuring instrument's type -approval certificate.  
1.1.1  
mechanical grain tester  
a mechanical device containing a measuring and filling container and accessories needed for their use, 
for example an alignment knife, a slider  or ring for the measuring container, etc. The device must 
permit adjustment.  
The manner in which the grain is poured into the measuring container may cause mea surements using 
a variety measuring instruments to differ and lead to measurement errors.It is therefore necessary to 
ensure that these measuring instruments are of suitable design, size, shape  and material.  
1.1.2  
automatic grain tester  
an automatic device, stand -alone or part of other measuring instruments —multi -parameter grain 
analysers  
Measurement is based on calculation of a calibration curve, the ability to shift and tilt it, and 
monitoring of measuring instrument drift.The resulting measurement of bulk density is displayed 
directly in  kg·hl-1. 
1.2 
mass per hectolitre (bulk density)  
specification of bulk density, i.e. the weight to volume ratio of grain after controlled pouring into a 
measuring container under precisely stipulated conditions, or u sing a calculation formula2; it is 
expressed in kg·hl-1 
1.3 
concurrence among grains  
a method to establish continuity between grain testers  
2 Metrological requirements  
2.1 Specified operating conditions  
Grain testers are used under the following specified operating conditions:  
Ambient temperature:  at least +10  °C to +30  °C. 
Relative humidity:  a maximum of 85  %. 
Cereals:  must be free of coarse admixtures and contaminants3, and the 
temperature of the measured cereal must be the same as the ambient 
temperature  around the measuring instrument.  
                                                      
2 ČSN  EN ISO 7971 -3:2010. Cereals —Determination of bulk density, called mass per hectolitre —
Part 3:Routine method, Annex  A 
3 ČSN  46 1011 -6 Testing of cereals, pulses and oilseeds —Part 6:Testing of cereals —Determination of grain 
admixtures and impurities content  Measure of a General Nature No  0111 -OOP -C058 -16 
3 Vibration:  the grain tester must be placed on a flat and solid foundation in order to 
prevent vibration and shaking.  
The grain tester must be protected from extreme temperatures, air humidity  and dust.  
All parts of the gra in tester must be marked with a serial number and must not be interchanged.In the 
event of any deformation or damage, they must be discarded.Parts must be clean during 
measurement.The measuring instrument must be assembled in a precise manner, and with ser ial 
numbers easily accessible and visible to operators.  
2.2 Rated measurement range  
Table  1 specifies the bulk density measurement range for individual crops.  
Table  1— - Rated measurement range  
Crop  From  [kg·hl-1] To [kg·hl-1] 
Wheat  61.6 88.1 
Barley  44.9 81.6 
Rye 35.3 66.1 
Oats 54.8 84.7 
The manufacturer may specify a different measurement range, and a different range may also be 
specified for other crops.  
2.3 Maximum permissible error  
2.3.1 Maximum permissible error of a grain tester  
The maximum permissible error of a grain tester is ±0.3  kg·hl-1 for bulk volume of 70 kg·hl-1. 
The maximum permissible error of a grain tester is ±0.4  kg·hl-1 for bulk volume of 70 kg·hl-1. 
2.3.2 Repeatability limit  
Repeatability pi—the difference between the highest and lowest bulk volume value after repeated 
measurement of an identical sample must not exceed 0.3  kg·hl-1. 
3 Technical requirements  
All components must be made with resistant and durable material.Components must not deform 
during use.  
It is necessary to take into account the fact that the measurement result is influenced by the manner of 
pouring and cutting off the measured content in the measuring container, the density of cereals and 
space between grains, and their size and shape.Repeated m easurement of cereal samples reduces the 
coefficient of friction between grains and increases bulk density.  
Examples of two types of mechanical grain testers are given in Annex  1 and 2.  
3.1 Mechanical grain tester  
The mechanical device must comprise a meas uring and filling container and accessories needed for 
their use, for example a slider and a knife.  Measure of a General Nature No  0111 -OOP -C058 -16 
4 3.2 Automatic grain tester  
Appropriate calibration curves and recommended volumes of cereals for measurement are stipulated 
for various types of cereals.  
The device must make it possible to clearly select, shift  and tilt the calibration curve.  
3.3 Scales  
Scales must comply with requirements for non -automatic scales4 and the following requirements: 
 Accuracy class II scales with corresponding weighing capacity:  
 for 1  L grain testers , scales with  d = 0.1  g, e = 10 d are used;  
 for 1  L grain testers , scales with  d = 0.01  g, e = 10d are used.  
3.4 Measuring instrument security and fraud protection 
The locations where a mechanical as well as automatic grain tester measuring instrument must be 
secured against unauthorised changes are specified in its type -approval certificate.  
3.5 Transport and storage  
During transport and storage, the grain tester must be protected from physical damage and corrosion.  
4 Measuring instrum ent labelling  
4.1 Markings on the measuring instrument  
The following information must be indicated on the measuring instrument:  
a) the nominal volume of the measuring container or hopper;  
b) the type -approval mark;  
c) the manufacturer or the manufacturer's trademar k on the measuring container, the year of 
manufacture;  
d) the word 'up' on the top surface of the knife (if the measuring instrument includes a knife);  
e) the serial number (on all parts of a mechanical grain tester: the measuring container, the hopper  
or on the  filler and flange, the knife, on the reinforced centre of the upper side of the slider; on 
the data plate of an automatic grain tester; the data plate can also apply to the measuring 
instrument, with which for example a multi -parameter hygrometer is combi ned).  
4.2 Placement of the official mark  
The official mark is placed on the data plate, and in the case of a mechanical grain tester also on the 
measuring container and other components.Security labels are used to secure points of entry that 
influence accuracy  (adjustment elements) and correct measurement.  
5 Type approval of the measuring instrument  
Measuring instrument testing during type approval includes:  
a) an external inspection;  
b) measurement of the dimensions and weight of measuring instrument components acco rding to 
technical documentation;  
c) accuracy and repeatability tests.  
                                                      
4 Government Regulation No  121/2016 on conformity assessment of non -automatic scales when being placed 
on the mark et Measure of a General Nature No  0111 -OOP -C058 -16 
5 5.1 Number of sample measuring instruments for testing  
Three sample measuring instruments are tested.  
5.2 External inspection  
During the external inspection, the measuring instrument's condition, data plate, and serial numbers 
are checked, and that all components are intact.  
All internal surfaces must be clean and bear no signs of damage.  
5.3 Measurement of the dimensions and weight of all measuring instrument components  
The dimensions a nd weight of the tested measuring instrument's components are tested, for example in 
accordance with Annex  P.1 or P.2 or the manufacturer's technical documentation.  
5.4 Accuracy and repeatability tests  
5.4.1 Test equipment requirements  
Required reference s tandards, measuring instruments, and aids:  
 a primary reference standard or secondary reference standard with class I or II bulk density;  
 highly accurate scales d = 0.01  g for volumes ≤1  L, d = 0.1  g for volumes >1  L; 
 a slide gauge with a 0 –250 mm range and  resolution of at least 0.1  mm; 
 a slide depth gauge with a 0 –300 mm range and resolution of at least 0.1  mm; 
 a registration thermometer (with accuracy 1 °C) with a hygrometer (with maximum relative 
humidity error 5 ), for measuring laboratory conditions;  
 grain screens with appropriately sized openings for the type of cereal5 (e.g. 2.00  mm for wheat);  
 a hygrometer for cereals, measurement range 5  %–45 % with a 0.1  % scale interval;  
 a series of samples of cereals, oilseeds  and pulses for which the grain tester is declared, free of 
admixtures and contaminants (maximum admixture and contaminant content of 2  %), free of 
mould and other changes, with the following bulk density:  
- for wheat:3 samples of food -grade or hard wheat for ea ch bulk density range:72 –78 kg/hl 
and 77 –83 kg/hl;  
- for barley:3 samples of barley for each bulk density range:61 –67 kg/hl and 67 –73 kg/hl;  
- for other crops, sets of 3 samples each are used for bulk density values 15  %–30 % from the 
measurement range limits;  
for the aforementioned series of cereal, oilseed  and pulse samples, the following also applies:  
- the minimum difference in bulk density between two samples used is at least 5  kg/hl;  
- the relative humidity of samples is in the range 9 –14 . 
Reference standar ds and measuring instruments must have valid, traceable calibration.If the measuring 
instrument being tested uses a knife to measure off volume, the grain sample must not be used for 
testing more than 50x.  
5.4.2 Reference conditions  
During testing, the tem perature of the laboratory environment must be within the range (20  5) °C, 
and air humidity must not exceed 60 .The rate of temperature fluctuations must not exceed 1  °C/h.  
Prior to testing, the measuring instruments and test samples are given at least 10 hours to adjust to the 
laboratory environment.  
                                                      
5 ČSN  46 1011 -6 Testing of cereals, pulses and oilseeds —Part 6:Testing of cereals —Determination of grain 
admixtures and impurities content  Measure of a General Nature No  0111 -OOP -C058 -16 
6 5.4.3 Determining repeatability and measuring instrument errors  
Measurement of metrological parameters using the method of direct continuity by grain is used to 
determine repeatability piand error pi,2-mof the grain tester under test for each sample of cereals by 
comparing averages from two measurements on the tested grain tester pi with the bulk density value 
pim determined by a secondary class I or II bulk density reference standard or a primary refere nce 
standard.  
Repeatability pi is calculated as follows:  
2 1 i i i p p p 
 (1) 
The average of 2 measurements
ip is calculated as follows:  
22 1 i i
ip pp
 (2) 
The error of the tested measuring instrument pi,2-m is calculated using the following 
relationship : 
i mi m-i,2 p p p ,
 (3) 
where:  pi1, pi2  ..... is a measurement of the bulk density of a cereal sample using the tested measuring 
instrument;  
 
ip  ..........  is the average of 2 measurements of the bulk  density of one cereal sample using the 
tested measuring instrument;  
 pim  ..........  is the bulk density of the cereal sample determined by the reference standard;  
 pi,2-m  ...... is the error of the tested measuring instrument.  
5.5 Criteria for compliance with requirements  
5.5.1 Measurement of measuring instrument components  
Measured component dimension and weight values are compared with values in the manufacturer's 
technical documentation or in Tables  1 and 2 in Annex  1 or Figure  2 in Annex  2.The values and 
design of individual components must agree with specified values.  
5.5.2 Accuracy test —determining measuring instrument error  
The maximum error of each cereal sample must not exceed the maximum permissible error specified 
in Article  2.3.1.  
5.5.3 Determining r epeatability  
The repeatability value must not exceed the repeatability limit specified in Article  2.3.2.  
6 Initial verification  
6.1 Visual inspection  
The visual inspection serves to check whether the grain tester submitted for verification conforms to 
the approved type in accordance with Article  5.2 and whether it has not been physically damaged.  Measure of a General Nature No  0111 -OOP -C058 -16 
7 6.2 Measurement of dimensions and weight  
Measurement is performed pursuant to Article  5.3. 
6.3 Functional tests  
An accuracy and repeatability test pursuant to Arti cle 5.4.1 is performed.  
 for wheat:1 sample of food -grade or hard wheat for each bulk density range:72 –78 kg/hl and 
77–83 kg/hl;  
 for barley:1 sample of barley for each bulk density range:61 –67 kg/hl and 67 –73 kg/hl;  
 for other crops, one sample of each is us ed with a bulk density 15  %–30 % from the outer limit 
of the measurement range of values;  
 the minimum difference between two samples used is at least 5  kg/hl;  
 the relative humidity of samples is in the range 9 –14 ; 
 if the measuring instrument being tested  uses a knife to measure off volume, the grain sample 
must not be used for testing more than 50x.  
6.4 Criteria for compliance with requirements  
Criteria pursuant to Article  5.5 apply.  
7 Subsequent verification  
During subsequent verification, an external inspection is performed pursuant to Article  6.1 and an 
accuracy and repeatability test pursuant to Article  6.3. 
During subsequent verification the maximum permissible error and repeatability error pursuant to 
Article  2.3 must be met.  
8 Examination at the request of a concerned person in accordance with 
§ 11a 
Users of legally controlled measuring instruments shall, at the request of a person who may be 
affected by inaccurate measurement, request examination of the legally controlled measuring 
instrument.The  grain tester must meet the metrological requirements specified in Chapter  5.4.3 of this 
Measure.  
Re-examination consists of the following tests:  
a) accuracy test —determining measuring instrument error;  
b) determining repeatability.  
In the evaluation, the maximu m permissible errors pursuant to Article  2.3 are used.  
9 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 ste mming 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 (herei nafter referred to as ‘notified standards’).The CMI will publish a 
list of these notified standards attached to the relevant measures, together with the general measure, in 
a manner accessible to the public (on www.cmi .cz). Measure of a General Nature No  0111 -OOP -C058 -16 
8 Compliance with notified standards or parts thereof shall be considered, to the extent and under the 
conditions defined in a general measure, as compliance with those requirements defined in this 
measure to which these standards or parts thereof appl y. 
Compliance with notified standards is one way of demonstrating compliance with the 
requirements.These requirements may also be met by using another technical solution guaranteeing an 
equivalent or higher level of protection of legitimate interests.  
 
 
II. 
G R O U N D S  
Pursuant to §  14(1)(j) of the Metrology Act, the CMI has issued this Measure of a General Nature 
toward the implementation of §  6(2), §  9(1) and (9), and  § 11a(3) of the Metrology Act, laying down 
metrological and technical requirements for speci fied measuring instruments and tests for type 
approval and verification of specified measuring instruments — grain testers.  
Decree No  345/2002 specifying the measuring instruments for mandatory verification and measuring 
instruments subject to type  approval , as amended, classifies this type of measuring instrument as one 
subject to verification under Item  2.1.6 in the Annex 'List of Specified Measuring Device Types'.  
This legislation (Measure of a General Nature) will be announced in accordance with Directiv e 
(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 §  172(l), in conjunction with §  39(l) CAP, the CMI has stipulated a time limit for 
comments of 30  days as of the date of posting on the official notice board.Comments submitted after 
this time limit will not be considered.  
The persons concerned are h ereby invited to comment on this draft Measure of a General Nature.With 
a view to the provisions of §  172(4) CAP, the comments shall be submitted in writing.  
In accordance with §  174(l) CAP in conjunction with §  37(l) CAP, it must be clear who is making th e 
comments, which measure of a general nature they concern, how it contradicts legislation or how the 
measure of a general nature is inaccurate, and they must be signed by the person making them.  
The supporting documents for this draft general measure may be consulted at the Czech Metrology 
Institute, Legal Metrology Department, Okružní 31, 638 00 Brno, after making arrangements by 
telephone.  
This general measure shall be posted for 15  days.  
 
 
 
 
 RNDr.Pavel Klenovský m.p.  
Director -General  
Person responsible for accuracy:Mgr.Tomáš Hendrych  Measure of a General Nature No  0111 -OOP -C058 -16 
9 Posted on:1  June 2018   
Signature of the authorised person confirming 
posting:  Mgr.Tomáš Hendrych m.p.  
  
Removed on:   
Signature of the authorised person confirming 
removal:   Measure of a General Nature No  0111 -OOP -C058 -16 
10 Annex  1 
A description of the measuring instrument and use of a 1  L grain tester model 1938 and 
a ¼ L tester  
1 Measuring instrument description  
The measuring instrument comprises the following parts (see Figure  1): 
a) hopper;  
b) filler;  
c) measuring container with ring, slider  and knife.  
The as sembled measuring instrument is secured in the mounting flange on the base plate.  
1.1 Hopper  
 must be made of metal;  
 must by cylindrical with vertical walls, sealed on the bottom end by a flat bottom;  
 the upper edge must have a reinforced flange to counter deformation;  
 the hopper for a 1  L tester must have a line along the circumference of its interior marking a 
volume of 1  350 ml, located at least 1  cm and at most 3  cm from the open end of the cylinder;  
 the hopper for a ¼  L tester must have a line along the  circumference of its interior marking a 
volume of 400  ml, located at least 1  cm and at most 3  cm from the open end of the cylinder.  
1.2 Filler  
 must be made of metal;  
 must be cylindrical with vertical walls, open at both ends;  
 its bottom must make it possi ble for it to be mounted on the ring on the upper part of the measuring 
container; the connection must be secure;  
 it must be capable of containing the full amount of grain measured out by the hopper.  
1.3 Measuring container with ring  
 a 1 L or ¼  L volume is  demarcated by the inner surface of the container walls, the upper surface of 
the inserted slider, and the bottom surface of the inserted knife; the maximum allowable relative 
error of the content is ±0.003  L for a 1  L and ±0.003  L for a ¼  L grain tester;  
 the wall of the measuring container must be made from a drawn brass or seamless stainless steel 
pipe;  
 it must be cylindrical with vertical walls, open at the top, the measuring edge must be reinforced 
and perpendicular to the container axis;  
 a ring must be  attached above the measuring edge with the same diameter as the container, at a 
distance that permits the knife to be inserted easily without excessive play;  
 the bottom of the measuring container must be level and perpendicular to the container's axis, wi th 
openings for air to escape during measurement;  
 the bottom edge must be reinforced; the reinforcement is of one piece with three mounting legs 
welded to the wall of the measuring container.  
1.3.1 Slider  
 must be made of brass sheet metal with a smooth sur face, shaped like a closed cylinder, with 
vertical walls and horizontal ends;  
 inside it must be reinforced so that an official mark can be affixed without damage or deformation.  
1.3.2 Knife  
 the knife edge must be made of hardened steel sheet metal, with st raight and parallel surfaces;  
 when fully inserted, it must cover the entire cross -section of the measuring container;  
 the knife blade but be v -shaped, open in the direction of insertion;  
 the sharp edge must run through the centre of the thickness of the sh eet metal blade.  Measure of a General Nature No  0111 -OOP -C058 -16 
11 1.6 Flange  
 must be metal and ensure a secure connection with the measurement container with a simple 
rotation;  
 it must be securely attached to a mounting plate or transport crate made of hard wood;  
 the mounting plate or crate must have levelling screws to place the measuring instrument in a stable 
vertical position.  
2 Scales  
 must comply with Article  3.3 of this Measure;  
 accuracy class II balance scales that are equipped with a counterweight to balance out the empty 
measuring container an d slider may be used.  
Other details are provided by relevant technical standards6. 
 
3 Measuring instrument drawing and dimensions  
 
Figure  1—A depiction of the parts of a 1  L grain tester model 1938 and a ¼  L grain 
tester  
Odměrná nádoba  Measuring container  
Nuž Knife  
Násypka  Hopper  
Plnič  Filler  
                                                      
6 ČSN  EN ISO 7971 -3:2010. Cereals —Determination of bulk density, called mass per hectolitre —
Part 3:Routine method,  Annex  A Informative description of the dimensions and use of a KERN device  
ČSN  99 4178  GRAIN TESTERS, Secondary reference standards of order 1 and 2 and operating measuring 
instruments, Technical requirements, Article  15 Measure of a General Nature No  0111 -OOP -C058 -16 
12 Běhoun  Slider  
 
3.1 1  L grain tester model 1938  
One-litre model 1938 grain testers must meet requirements pursuant to the following table.  
Table  1—Dimensions of individual parts of a 1  L grain tester, model 1938  
Hopper  inner diameter  (86 ± 0.2)  mm 
volume up to line  (1 350 ± 10)  ml 
Filler  inner diameter  (79 ± 0.1)  mm 
wall thickness  (1 ± 0.2)  mm 
height above inserted slider  (280 ± 2)  mm 
Slider  diameter  (87.5 ± 0.1)  mm 
height  (40 ± 0.2) mm 
weight  (450 ±2)  g 
Knife  angle on edge  (90 ± 2)  ° 
sheet metal thickness  (1 ± 0.05)  mm 
angle length  (3 ± 0.5)  mm 
Measuring container  inner diameter  (88.2 ± 0.1)  mm 
wall thickness  (1.2 ± 0.5)  mm 
inner height above slider  (163.7 ± 0.1)  mm 
bottom thickness  (4.5 ± 0.1)  mm 
number of openings in bottom  85 
diameter of openings in bottom  (3 ± 0.1)  mm 
distance between bottom and flange  (6 ± 0.1)  mm 
outer reinforcement of upper edge —
thickness  (2.5 ± 0.5)  mm 
outer reinforcement of upper edge —
height  (6 ± 1)  mm 
height of legs  (9 ± 0.1)  mm 
diameter of legs  (6 ± 0.1)  mm 
Measuring container 
ring inner diameter  (88.2 ± 0.1)  mm 
height  (40.5 ± 0.1)  mm 
Flange  diameter of ring for attachment  (80 ± 0.1)  mm 
 
3.2 Quarter -litre grain tester  
Quarter -litre grain testers must comply with requirements in Table  2. Measure of a General Nature No  0111 -OOP -C058 -16 
13 Table  2—Dimensions of individual parts of a ¼  L grain tester  
Hopper  inner diameter  (52.0 ± 0.2)  mm 
wall thickness  (1.0 ± 0.2)  mm 
volume  (0.40 ± 0.01)  L 
Filler  inner diameter  (50.0 ±  0.2) mm 
wall thickness  (0.88 ± 0.12)  mm 
height above inserted slider  (210 ± 1)  mm 
Slider  diameter  (52.5 ± 0.1)  mm 
height  (23.0 ± 0.5)  mm 
weight  (90 ±1)  g 
Knife  angle on edge  (90 ± 2)  ° 
sheet metal thickness  (1 ± 0.05)  mm 
angle length  (3 ± 0.5) mm 
Measuring container  inner diameter  (53.2 ± 0.2)  mm 
wall thickness  (0.88 ± 0.12)  mm 
Permitted deviation from circularity  (0.10 ± 0.05)  mm 
Volume  (0.250 ± 0.001)  L 
bottom thickness  (3.0 ± 0.1)  mm 
number of openings in bottom  25 
diameter of openings in bottom  (3.0 ± 0.1)  mm 
distance between bottom and flange  (5.75 ± 0.75)  mm 
 
 
4 Grain tester measurement procedure  
The test sample of grain is poured freely from the sampler into the hopper up to the volume line.  
The measured -out grain is poured from the hopper into the filler from a height of about 4  cm into the 
centre of the filler; pouring takes about 12  seconds for a 1  L tester and about 8  seconds for a ¼  L 
tester.During this time the operator must not touch the filler.  
While holding th e measuring container in order to keep it steady, the knife is pulled out with a quick 
motion.This releases the slider and it falls into the measuring container along with the grain.  
The knife is then placed into the slit in the measuring container and is inserted completely with a quick 
motion.This cuts off a volume of 1  L (¼  L) of grain in the measuring container.No vibrations must 
occur during use until the grain is separated in the measuring container.If the knife is slowed down by 
cutting grains, the m easurement must be repeated.  
The measuring container and filler are removed from the flange, excess grain above the knife is poured 
out, and the filler is removed.Depending on the taring method, the measuring container is weighed 
with or without the knife;  the measured -out grain may also be poured into another container and 
weighed.  
Before every subsequent measurement, the measuring container, slit, and slider must be cleaned of all 
contaminants, and the grain remnants above the knife are mixed with the gra in from the measuring 
container.  Measure of a General Nature No  0111 -OOP -C058 -16 
14 5 Expressing results  
1 L grain tester  
for wheat:  0.1002 · m + 0.53  
for barley:  0.1036 · m - 2.22 
for rye:  0.1017 · m - 0.08 
for oats:  0.1013 · m - 0.61 
for malt:  100 · m 
where  m is the mass of the cereal sample measured out by the tester.  
To calculate mass per hectolitre of wheat, barley, rye  and oats, the 1  L grain tester model 1938 is 
equipped with calculation tables created using the above formula s. 
Additional details are prov ided in the relevant technical standard7. 
6 Measuring instrument security and fraud protection  
The position of the flange with respect to the measuring container must be protected from 
unauthorised changes.  
7 Transport and storage  
During transport and storage, the grain tester must be protected from physical damage and corrosion.  
                                                      
7ČSN  EN ISO 7971 -2 Cereals —Determi nation of bulk density, called mass per hectolitre —Part 3:Routine 
method, Annexes  A, B  Measure of a General Nature No  0111 -OOP -C058 -16 
15 Annex  2 
A description of the measuring instrument and use of a 1  L 'Niléma litre' grain tester  
1 Measuring instrument drawing and dimensions  
The measuring instrument comprises the parts shown in Figure  2. 
 
 
121 int.  121 int. 
192 ext.  192 ext. 
 
Legend:  
1 - hopper  
2 - spacer rulers  
3 - knife  
4- measuring container with ring  
 
The volume of the measuring container is 1  L. 
Measure of a General Nature No  0111 -OOP -C058 -16 
16  
Figure  2—Drawing of a Niléma litre grain tester.Dimensions are given in millimetres.  
 
1.1 Hopper  
 a hopper with a conical outlet with a closure that directs grain flow;  
 connecting the spacer ruler to the ring of the measuring container, which allows the knife to move 
horizontally in the slit.  
1.2 Measuring container  
 must be a co -axial cylinder with vertical walls, volume 1  L, open at both ends.  
1.3 Knife  
 a flat knife with a sharp 'v' edge, open in the direction of insertion.  
2 Scales  
 must comply with Article  3.3 of this Measure of a General Nature;  
 accuracy class II balance scales that are equipped with a counterweight to balance out the empty 
measuring container may be used.  
Other details are provided by relevant technical standards8. 
3 Grain tester measurement procedure  
Scales (1.1.3) are used to weigh the empty measuring container to the nearest 1  g. 
The test sample of grain is poured freely without compaction into the hopper up to its volume line or 
to its edge.  
The hopper closure is opened and the grain is allowed to pour into the measuring cont ainer.  
The knife is inserted carefully and quickly into the slit in the measuring container ring.It is necessary 
to hold the container firmly in place to prevent vibrations and shaking that would compact the grain.  
The measuring container is weighed with t he cut -off volume of grain to the nearest 1  g. 
4 Expressing results  
Bulk density ƿ, expressed in  kg·hl-1 is given by the following formula:  
𝑝=𝑚
1000×100
𝑉=𝑚
10𝑉 (4) 
where: m  .....  the mass of the cereal sample measured out by the tester in grams, calculated u sing the 
following formula:  
m = (m1 - m0)  (5) 
where: m0  ....  the mass in grams of the empty measuring container;  
m1  ...  the mass in grams of the measuring container with the measured -out grain.  
Additional details are provided in the relevant technical standard9. 
                                                      
8 ČSN  EN ISO 7971 -3:2010. Cereals —Determination of bulk density, called mass per hectolitre —
Part 3:Routine method, Annex  A Informative description of the dimensions and use of a KERN device  
ČSN  99 4178  GRAIN TESTERS, Secondary reference standards of order 1 and 2 and operating measuring 
instruments, Technical requirements, Article  15 Measure of a General Nature No  0111 -OOP -C058 -16 
17 5 Measuring instrument security and fraud protection  
The position of the spacer rulers with respect to the measuring container must be protected from 
unauthorised changes.  
6 Transport and storage  
During transport and storage, the grain tester must be pro tected from physical damage and corrosion.  
                                                                                                                                                                      
9 ČSN  EN ISO 7971 -2 Cereals —Determination of bulk density, called mass per hectolitre —Part 3:Routine 
method, Annexes  A, B