FINAL DRAFT UGANDA 
STANDARD  
  FDUS 1022 -1 
Second Edition  
2012 -mm-dd 
 
 
 Reference number  
FDUS 1022 -1: 2012  
© UNBS 2012   
  
Material measures of length for general use  — Part 1: 
Metrological and technical requirements  
 FDUS 1022 -1: 2012  
ii © UNBS 2012 – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions  of a contract. Users are 
responsible for its correct application  
© UNBS 2013   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photo copying and microfilm, without prior written 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: 256 41 4 505 995  
Fax: 2 56 41 4 286 123  
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  FDUS 1022 -1:2012  
© UNBS 2012 – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Terms and definitions  ................................ ................................ ................................ ...........................  1 
2.1 Metrological characteristics  ................................ ................................ ................................ .................  1 
2.2 Types of measures  ................................ ................................ ................................ ................................  2 
2.3 Influences and reference conditions  ................................ ................................ ................................ ... 2 
3 Symbols,  units  and abbreviated terms  ................................ ................................ ...............................  3 
4 Requirements  ................................ ................................ ................................ ................................ .........  3 
4.1 Metrological requirements  ................................ ................................ ................................ ...................  3 
4.1.1  Accuracy classes  ................................ ................................ ................................ ................................ .. 3 
4.1.2  Maximum permissible error on initial verification  ................................ ................................ .............  3 
4.1.3  Maximum permissible err or in service  ................................ ................................ ................................  4 
4.1.4  Rated operating conditions  ................................ ................................ ................................ ..................  4 
4.1.5  Reference conditions  ................................ ................................ ................................ ............................  5 
4.2 Technical requirements  ................................ ................................ ................................ ........................  5 
4.2.1  Nominal length  ................................ ................................ ................................ ................................ ....... 5 
4.2.2  Materials  ................................ ................................ ................................ ................................ .................  5 
4.2.3  Construction  ................................ ................................ ................................ ................................ ..........  6 
4.2.4  Scale  ................................ ................................ ................................ ................................ .......................  8 
4.2.5  Numbering  ................................ ................................ ................................ ................................ ..............  9 
4.2.6  Indicating devices  ................................ ................................ ................................ ................................ . 9 
5 Marking  ................................ ................................ ................................ ................................ .................  10 
6 Metrological controls  ................................ ................................ ................................ ..........................  11 
6.1 General  ................................ ................................ ................................ ................................ .................  11 
6.2 Type approval  ................................ ................................ ................................ ................................ ...... 11 
6.3 Initial verification  ................................ ................................ ................................ ................................ . 11 
6.4 Periodic verification  ................................ ................................ ................................ ............................  11 
6.5 Uncertainty of measurement  ................................ ................................ ................................ ..............  11 
7 Verification (or control) marks  ................................ ................................ ................................ ...........  11 
Annex A (normative)  Technical requirements particular to various types of measures  .........................  12 
A.1 General  ................................ ................................ ................................ ................................ .................  12 
A.2 Measures for short lengths  ................................ ................................ ................................ ................  13 
A.2.1  Semi -rigid steel tape measures in a case  ................................ ................................ .........................  13 
A.2.2  Semi -rigid ste el tape measures with digital readout  ................................ ................................ ....... 14 
A.2.3  One-piece rigid or semi -rigid measures ................................ ................................ ............................  15 
A.2.4  Flexible tape measures made of fi breglass and plastics or other suitable non -metallic 
materials, not in a case  ................................ ................................ ................................ .......................  16 
A.2.5  Folding measures made of metal or other materials  ................................ ................................ ....... 17 
A.2.6  Telescopic measures made of metal or other materials  ................................ ................................ . 18 
A.2.7  Telescopic measures made of metal or other materials with digital readout  ...............................  19 
A.3 Measures for long lengths  ................................ ................................ ................................ ..................  20 
A.3.1  Flexible steel tape measures with winding device not designed for measuring lengths 
greater than their nominal length by rep eated use of the same tape  ................................ ............  20 
A.3.2  Flexible steel tape measures with tensioning weight or sinker  ................................ .....................  21 
A.3.3  Flexible steel tape m easures with tensioning weight or sinker equipped with electronic 
sensing  ................................ ................................ ................................ ................................ .................  23 
A.3.4  Flexible steel surveyor's tapes designed for measuring lengths greater than their nominal 
length by repeated use of the same tape  ................................ ................................ ..........................  24 FDUS 1022 -1: 2012  
iv © UNBS 2012 – All rights reserved  
 A.3.5  Flexible tape measures made of fibreglass and plastics or other suitable nonmetallic 
materials  ................................ ................................ ................................ ................................ ..............  25 
Annex B (informative)  Test requirements  ................................ ................................ ................................ .... 27 
B.1 Test requirements for material measures of length  ................................ ................................ ........  27 
B.1.1  External examination  ................................ ................................ ................................ ..........................  27 
B.1.2  Accuracy tests  ................................ ................................ ................................ ................................ .... 27 
B.2 Test requirements for material measures fitted with ancillary electronic devices  ......................  28 
B.2.1  General requirements  ................................ ................................ ................................ .........................  28 
B.2.2  Accuracy tests for indicating devices  ................................ ................................ ..............................  28 
B.2.3  Accuracy tests for flexible steel tape measures with tensioning weight or sinker equipped 
with electronic sensing  ................................ ................................ ................................ ......................  28 
B.2.4  Environmental classification  ................................ ................................ ................................ ............  28 
B.2.5  Influence and disturbance tests for ancillary electronic devices fitted to material 
measures of length  ................................ ................................ ................................ .............................  28 
Bibliography  ................................ ................................ ................................ ................................ .....................  30 
 
 FDUS 1022 -1:2012  
© UNBS 2012 – All rights reserved  v 
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Tourism, Trade and 
Industry established under Cap 327 , of the Laws of Uganda.  UNBS is mandated to co -ordinate the 
elaboration of standards and is  
(a) a member of In ternational Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT/SPS Agreements of the World Trade Organisation (WTO).  
The work of preparing Ugan da Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of representatives of 
consumers, traders, academicians, manufacturers, government and other stak eholders.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda  Standards by the National Standards Council.  
This Final Draft Uganda S tandard is based on OIML R 35 Material measures of length for general use . 
Committee membership  
The following organizations were represented on the Metrology  standards Technical Committ ee (UNBS/TC 9), 
during the development of this standard:  
 Civil Aviation Authority.  
 Kampala City Traders Association  (KACITA)  
 Kyambogo University Kampala  
 Makerere University Kampala  
 Ministry of Defense  
 Ministry of Energy  
 Ministry of Internal Affairs  
 Ministr y of Works and Transport  
 National Environmental Management Authority  (NEMA)  
 Uganda National Bureau of Standards  
 UMEME  
 
 
 FINAL DRAFT UGANDA STANDARD  FDUS 1022 -1: 2012  
 
© UNBS 2012 – All rights reserved  1 
 Material measures of length for general use  — Part 1: 
Metrological and technical requirements  
1 Scope  
This Final Draft Uganda Standard  applies to material measures of length for general use, hereinafter  called 
“measures”.  This standard  specifies the technical, metrological and administrative conditions  which are 
mandatory for these measures.  It also  includes the requirements for digital readouts on the cases of tapes,  
whether electronic or mechanical.  
This standard  does not apply to high -precision measures used by industry in the  field of mechanics or in 
geodesy (for example: gauge blocks, geodetic wires  and precision line measures).  
It also does not address safety aspects, for example the use of material  measures with electronic devices in 
hazardous areas. Guidelines for these aspects should be followed  in accordance with the applicable 
international, regional or national regulations, whi ch are often  detailed in standards.  
2 Terms and definitions  
For the purposes of this standard, the following terms and definitions shall apply . 
2.1 Metrological characteristics  
2.1.1  
material measure of length  
material measure provided with scale marks, th e distances between which are indicated in legal units of 
length  
2.1.2  
nominal length  
length by which the measure is designated  
2.1.3  
principal scale marks  
two scale marks, the distance between which represents the nominal length of the measure  
2.1.4  
scale 
set of all the scale marks and associated numbering  
2.1.5  
scale interval  
value expressed in units of length of: the difference between  
 the values corresponding to two consecutive scale marks, for analog indication , and   
 two consecutive indicated values  for digital indicatio n FDUS 1022 -1: 2012  
2 © UNBS  2012  – All rights reserved  
 2.2 Types of measures  
2.2.1  
end measure  
length measure which has the principal scale marks formed by two end surfaces or edges of the  measure  
2.2.2  
line measure  
length measure which has the principal scale marks formed by two lines , holes or marks  
2.2.3  
composite measure  
length measure which has one of the principal scale marks formed by an end surface or edge and the  other by 
a line, hole or mark  
2.2.4  
supplementary devices  
devices such as one or more fixed or movable hooks, ring s, handles, tips, winding devices, and  verniers 
intended to facilitate and extend the utility of the measure  
2.2.5  
indicating device  
part of the measure which displays the measurement result either continuously or on demand. An  electronic 
indicating device  comprise s of a sensor, transducer, calculator and indicator  
2.2.6  
ancillary device  
device intended to perform a particular function, directly involved in elaborating, transmitting or  displaying 
results  
2.3 Influences and reference conditions  
2.3.1  
influe nce quantity  
quantity that is not the subject of the measurement but which influences the values of the measurand  or the 
indication of the instrument.  
2.3.2  
influence factor  
influence quantity having a value within the specified rated operating conditions of the instrument.  
2.3.3  
disturbance  
influence quantity having a value within the limits specified in this standard , but outside the  specified rated 
operating conditions of the instrument.  
2.3.4  
rated operating conditions  
conditions of use, giving the rang e of values of influence quantities for which the metrological  characteristics 
are intended to lie within the specified maximum permissible errors.  
2.3.5  
reference conditions  
set of specified values of influence factors fixed to ensure valid intercomparis on of the results of  
measurements.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  3 
 3 Symbols, units and abbreviated terms  
m metre , unit of length , together with the authorized multiples and sub -multiples  
4 Requirements  
4.1 Metrological requirements  
4.1.1 Accuracy classes  
The material measures of length covered by this standard  belong to one of three accuracy classes, 
designated by the numbers I, II, and III, according to their accuracy.  
4.1.2 Maximum permissible error on initial verification  
4.1.2.1 The maximum permissible error on initial verification,  positive or negative,  under rated operating 
conditions  for 
a) nominal length, and  
b) any other distance between any two non -consecutive scale marks,  
is expressed by the formula:  
(a + b L) mm,  
where  
a and b are coefficients the values of which are given, for ea ch accuracy class, in Table 1 , and 
L   is the value of the length in question, rounded up to the nearest whole number of metres . 
Table 1 — Accuracy classes  
Accuracy class  a b 
I 0.1 0.1 
II 0.3 0.2 
III 0.6 0.4 
 
4.1.2.2 The maximum permissible error, posi tive or negative, for the scale interval, i, less than or  equal to 
1 cm, is given for each accuracy class in Table 2.  
Table 2 — Maximum permissible errors  
Scale interval, i Maximum permissible error  for the accuracy class  
mm 
i ≤ 1 mm  I II III 
1 mm < i ≤ 1 cm  0.1 
0.2 0.2 
0.4 0.3 
0.6 
 FDUS 1022 -1: 2012  
4 © UNBS  2012  – All rights reserved  
 For the scale interval greater than 1 cm, the maximum permissible error is expressed as a function of the 
length of the interval, by the formula:  
(a + b L) mm,  
where  
the values of the coefficients are equal to the values giv en in 4. 1.2.1 and  
L is the value of the length in question, rounded up to the nearest whole number of metres.  
4.1.2.3 The maximum permissible difference between the lengths, i, of two consecutive scale intervals, 
having a value less than or equal to 1 cm,  is given for each accuracy class, in Table 3.  
Table 3 — Maximum permissible difference  
Scale interval, i Maximum permissible error  for the accuracy class  
mm 
i ≤ 1 mm  I II III 
1 mm < i ≤ 1 cm  0.1 
0.2 0.2 
0.4 0.3 
0.6 
 
For the scale interval greater than 1 cm, the maximum permissible difference between the lengths of  two 
consecutive scale intervals is expressed, as a function of the length of the interval, by the formula:  
(a + b L) mm,  
4.1.2.4 However, for end or composite measures, the maximum permissible  error, positive or  negative, 
for the length of the terminal scale interval bounded by an end surface, is increased by:  
 0.1 mm for measures of class I,  
 0.2 mm for measures of class II,  and 
 0.3 mm for measures of class III.  
Moreover, the requirements set ou t in 4. 1.2.1 and 4 .1.2.3 do not apply  when one of the two : 
a) non-consecutive scale marks, referred to in 4. 1.2.1 b), is formed by an end  surface;  and 
b) consecutive scale intervals, referred to in 4. 1.2.3, is a terminal scale  division bounded by an end 
surface.  
4.1.3 Maximum permissible error in service  
The maximum permissible error in service, positive or negative, equals twice the maximum permissible error 
on initial verification given in 4. 1.2. 
4.1.4 Rated operating conditions  
4.1.4.1 Temperature  
The temperat ure limits shall be the reference temperature ±  8 °C or the temperature indicated on the  measure 
± 8 °C.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  5 
 4.1.4.2 Humidity  
The manufacturer shall specify whether the instrument is designed for condensing or non -condensing  
humidity.  
4.1.4.3 Electrical voltag e 
4.1.4.3.1  Batteries  
The upper limit of the voltage of a new or fully charged battery of the specified type  shall be designated as 
Ubmax and the lower limit , Ubmin as specified by the manufacturer.  
4.1.4.3.2  Mains power voltage variations  
The variations s hall be between –15 % to +10 % of nominal voltage.  
4.1.5 Reference conditions  
Testing shall be performed under the following reference conditions unless otherwise specified by the  
manufacturer:  
a) the measure is at the reference temperature  of 20 °C or the te mperature indicated on the measure  
(see 5.2). Tolerance ±  2 °C;  
b) ambient relative humidity range  of 45 % to 55 %;  
c) power source  whereby  the nominal (battery) voltage, or the voltage of a new of fully charged battery  is 
according to the manufacturer’s specifi cation;  and 
d) when the tension is specified, the measure shall be supported on a horizontal surface over the  total 
length under test, practically without friction, and shall be stretched out by the tension  indicated on the 
measure.  
4.2 Technical requirements  
4.2.1  Nominal length  
4.2.1 .1 The nominal length of the measures shall be an integral multiple of 0.5 m up to 15 m. Any  
nominal length between 15 m and 100 m shall be an integral multiple of 5 m, and any nominal length  over 100 
m shall be an integral multi ple of 50 m.  
4.2.1.2 Other values may be deemed appropriate for specific applications provided that the specific  
application is clearly indicated on the measure.  
4.2.1 .3 Land surveying measures shall have nominal lengths of 5 m, 10 m, 20 m, 50 m, 100 m or  200 m, 
as stipulated in A.3.2 .1. 
 
4.2.2  Materials  
4.2.2 .1 The measures and their supplementary devices shall be made of materials which, under  normal 
conditions of use, are sufficiently durable, stable, and resistant to environmental influences.  
4.2.2 .2 The properties of the materials used shall be such that:  FDUS 1022 -1: 2012  
6 © UNBS  2012  – All rights reserved  
 a) the expansion due to a temperature change of ±  8 °C from the reference temperature or the  
temperature indicated on the measure plus all other errors shall not exceed the maximum  permissible 
error for t he accuracy class to which the measure belongs;  and 
b) for measures which have to be used under a specified tension, a variation of ±  10 % of this  tension 
does not produce a variation in length exceeding the maximum permissible error.  
4.2.3  Construction  
4.2.3 .1 The measures and their supplementary devices shall be well and robustly constructed, and  
carefully finished.  
4.2.3 .2 The dimensions and shape of the cross -section of measures shall be such that, under normal  
conditions of use, measurements can be made w ith the degree of accuracy required for the accuracy  class to 
which the measures belong.  
4.2.3 .3 Tape measures shall be made in such a way that when the tape is stretched out on a flat  surface, 
its edges are virtually straight and parallel.  
4.2.3 .4 The sur faces forming the two principal scale marks (end surfaces) of end measures shall be  flat 
and perpendicular to the longitudinal axis of the measure.  
4.2.3 .5 The end surfaces of an end or composite measure made of wood or other material of  durability 
equal t o or less than that of wood shall be provided with a bracket, plate, or end fitting  which is resistant to 
wear and impact damage, and suitably attached to the measure.  
4.2.3 .6 Supplementary devices are permissible, provided they cannot cause confusion; the y shall be  
designed and attached to the measure in such a way that, under normal conditions of use, it is virtually  
impossible for the measurement uncertainty to increase.  
4.2.3 .7 Winding devices for tape measures shall be made in such a way that they do n ot cause any  
permanent deformation of the tape.  
4.2.3 .8 On certain types of measures, a blank length of the measure, extending beyond the principal  
scale mark at the end of the measure and long enough for verification purposes, may be provided  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  7 
 .
 
 
Figure  1 — Examples illustrating certain requirements  FDUS 1022 -1: 2012  
8 © UNBS  2012  – All rights reserved  
 4.2.4  Scale  
4.2.4 .1 The scale marking shall be clear, regular, indelible, and carried out in such a way that reading is 
definite, easy and unambiguous. Some non -numbered scale marks, not exceeding the number of scale marks 
between two consecutive numbered scale marks on the measure, may extend beyond the principal scale 
mark at the end of the measure.  
4.2.4 .2 The scale interval shall take the form  1 × 10n m, 2 × 10n m or 5 ×10n m, n being a positive or 
negativ e whole number or zero. Furthermore, the scale interval shall not exceed:  
 1 mm for measures with a nominal length of 0.5 m or 1 m, in relation to their accuracy;  
 1 cm for measures with a nominal length not greater than 2 m;  
 10 cm if the nominal length is g reater than 2 m and less than 10 m;  
 20 cm if the nominal length is equal to or greater than 10 m and less than 50 m;  and 
 50 cm if the nominal length is equal to or greater than 50 m . 
However, these values may be exceeded for specific applications, provided  the specific application is  
indicated on the measure.  
4.2.4 .3 When the scale marks are lines, these shall be straight, perpendicular to the axis of the measure, 
and shall all have the same width, which shall be constant throughout their length. The length  of the lines shall 
be related to the corresponding unit of measurement. The lines shall be such that they form a distinct and 
clear scale and that their width does not cause any measurement uncertainty.  
The maximum permissible width of the lines, in relat ion to the accuracy class and the scale interval of the 
measure is given in Table 4.  
An arrowhead or other equivalent symbol may be used to distinguish certain important scale marks.  
Table 4 — Maximum width of lines  
Scale interval of the measure  Maximum wi dth of the lines for the accuracy class  
I II and III  
Less  than or equal to 2 mm  0.2 mm  0.2 mm  
Greater than 2 mm  and less than or 
equal to 2 cm  0.2 mm  10 % of the scale interval  
Greater than 2 cm  0.2 mm  2 mm  
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  9 
 4.2.4 .4 Certain sections of the scale, p articularly towards the ends, may be subdivided into decimal  sub-
multiples of the scale interval adopted for the measure as a whole.  In that case, the width of the lines may be 
less in the areas of reduced scale intervals than on the rest of  the measure.  
4.2.4.5 Scale marks may also take the form of holes, if the scale interval is greater than or equal to  1 cm, 
or other marks, if the scale interval is greater than or equal to one decimetre, provided that these  marks 
ensure sufficiently precise reading, taki ng into account the accuracy class to which the measure  belongs.  
4.2.4 .6 A measure may have more than one scale, for which the scale intervals may be different.  
4.2.5  Numbering  
4.2.5 .1 Numbering shall be clear, regular, indelible, and carried out in such a  way that reading is  definite, 
easy, and unambiguous; the number of numbered scale marks shall be determined  accordingly.  
4.2.5 .2 Numbering may be fully sequential, or partially sequential and partially repetitive.  In the case 
covered by 4.2.4 .4 above, the  numbering in parts with reduced scale intervals may be different  from that for 
the rest of the measure.  
4.2.5 .3 The position, dimensions, shape, color and contrast of the numbers shall be appropriate to  the 
scale and the associated scale marks.  Depending on how the measure is to be read, numbers may be 
inscribed parallel or perpendicular to  the edge of the measure.  
4.2.5 .4 Whatever the scale interval, the numbers shall represent millimetres, centimetres,  decimetres, or 
metres and shall not be accompanied b y the corresponding symbols.  If the numbered unit is not the metre, the 
scale marks corresponding to metres may be numbered in  metres, in which case these numbers shall be 
followed by the symbol “m”; furthermore, the number of  preceding metres may be repea ted in the same way in 
front of the other numbered scale marks.  Millimetre scales shall be numbered every centimetre.  When the 
scale interval of a line measure is in the form of 2 × 10n and not less than 2 cm, all scale  marks shall be 
numbered.  
4.2.5 .5 On a measure with several scales, the numbering of these scales may be different and the  
numbering systems may increase in the same direction or in the opposite direction.  
4.2.6  Indicating devices  
4.2.6 .1 General aspects  
4.2.6 .1.1 Indicating devices may be us ed with semi -rigid steel tape measures with readout, telescopic  
measures and flexible steel tape measures with tensioning weight or sinker equipped with electronic  sensing.  
4.2.6 .1.2 The indicating device shall be in addition to the scale marks on the blad e. It shall provide an  
easily read, reliable and unambiguous visual indication of the indicated length throughout the whole  length of 
the measure.  
4.2.6 .1.3 The indicating device shall be able to display the indicated length up to and including the  nominal  
length of the measure.  
4.2.6 .1.4 The indicated length shall be expressed in metres (symbol “m”) or authorized multiples or  sub-
multiples. The appropriate symbol shall appear immediately adjacent to the indicated length.  
4.2.6 .1.5 The indicated length shal l be given by a line of adjacent digits appearing in one or more  
apertures. The advance of a given digit shall be completed while the digit of the next immediately  lower 
decade changes from 9 to 0.  
4.2.6 .1.6 The length indicated on the display shall agree with the measurement made by the blade to  the 
nearest scale interval of the blade.  FDUS 1022 -1: 2012  
10 © UNBS  2012  – All rights reserved  
 4.2.6 .1.7 There shall be no ambiguity in distinguishing between the length currently being measured  and 
alternative displays.  
4.2.6 .2 Electronic indicating devices  
4.2.6 .2.1 If the power source voltage drops below the manufacturer's specified minimum value, the  device 
either continues to function correctly, indicates an error signal or automatically goes out of  service.  
4.2.6 .2.2 On switch -on and optionally on demand, it shal l be possible to visually check the correct  
operation of the entire display. This shall comprise : 
 displaying all the elements (“eights” test);  
 blanking all the elements (“blank” test);  and 
 displaying “zeros” (“zeros” test).  
Each step of the sequence shall last at least 0.5 s.  
NOTE  Technical requirements specific  to various types of measures are found in Annex A.  
5 Marking  
5.1 The following inscriptions are mandatory in all cases:  
 nominal length (optional in a rectangle);  
 numeric code, trade mark or trade na me of the manufacturer and/or of his representative;  and 
 designation of accuracy class: I, II or III, in an oval.   
5.2 The following inscriptions are mandatory in certain cases:  
 reference temperature, if other than 20 °C (see 4 .1.4); 
 tension, if specified;  and 
 specific use for which the measure is intended, in the cases covered by 4.2.1  (nominal  length) and 
4.2.4.1  (scale interval).  
5.3 Nominal length, temperature, and tension shall be expressed in one of the units specified in  OIML 
International Document D  2 Legal units of measurement , followed by the corresponding legal  symbol.  
5.4 All of these marking s shall be clearly visible and readable, and placed at the beginning of  the measure 
or on the case of the measure if the case and measure are not separable.  
5.5 In addition, any other non -metrological inscriptions specified in particular regulations or  authorized by 
competent national authorities may appear on the measure.  
5.6 Advertising inscriptions may appear on the measures, provided the requirement of 5.7 is met.  
5.7 All inscriptions shall be arranged so that they do not interfere with the reading of the  measure.  
5.8 Under the sole responsibility of the manufacturer, the thermal expansion coefficient of the  material of 
which the measure is made, may be ind icated in the form α = .../°C or α = ... K–1. 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  11 
 6 Metrological controls  
6.1 General  
When material measures of length are subject to an individual country’s metrological controls, these  controls 
may include some or all of the controls below (according to th e country’s national  legislation).  
6.2 Type approval  
Each type of measure from each manufacturer is subject to type approval. Documentation to assist  type 
approval examination shall be supplied by the manufacturer or his authorized representative.  No modif ications 
may be made on an approved type without special authorization.  
6.3 Initial verification  
New, repaired and readjusted measures shall undergo initial verification tests. Documentation to assist  initial 
verification testing shall be supplied by the m anufacturer or his authorized representative.  
6.4 Periodic verification  
Periodic verification shall be carried out at fixed intervals on certain types of measures in use, as  required by 
national regulations.  
6.5 Uncertainty of measurement  
The uncertainty o f measurement should not be added to the error when determining compliance with  the 
maximum permissible error (see 4 .1.2). 
7 Verification (or control) marks  
Measures shall be constructed so that they can accommodate the verification (or control) marks  prescribed by 
national regulations; a space shall be provided for this purpose near the beginning of the  measure.  FDUS 1022 -1: 2012  
12 © UNBS  2012  – All rights reserved  
 Annex A  
(normative)  
 
Technical requirements particular to various types of measures  
A.1 General  
In addition to the general requirements covering a ll material measures of length, special technical  
requirements which shall be met by certain types of measures are given in this annex . This applies to two 
types of measures indicated below : 
a) measures for short lengths  which include:  
i. semi -rigid steel tape m easures in a case ; 
ii. semi -rigid steel tape measures with digital readout ; 
iii. one-piece rigid or semi -rigid measures ; 
iv. flexible tape measures made of fibreglass and plastics or other suitable non -metallic  materials, 
not in a case ; 
v. folding measures made of metal o r other materials ; 
vi. telescopic measures made of metal or other materials ; and  
vii. telescopic measures made of metal or other materials with digital readout.  
b) measures for long lengths  which include:  
i. flexible steel tape measures with winding device not designed f or measuring lengths  greater than 
their nominal length by repeated use of the same tape ; 
ii. flexible steel tape measures with tensioning weight or sinker ; 
iii. flexible steel tape measures with tensioning weight or sinker equipped with electronic  sensing ; 
iv. flexible  steel surveyor's tapes designed for measuring lengths greater than their  nominal length 
by repeated use of the same tape ; and  
v. flexible tape measures made of fibreglass and plastics or other suitable non -metallic  materials.  
measures with a nominal length f rom 5 m to 10 m may be made to conform to either of the two 
types  of measures . 
NOTE  The drawings on the f igures below  are given for guidance only. Manufacturers have  complete freedom in the 
manufacture of the measures, provided that they meet the statutory  requirements.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  13 
 A.2 Measures for short lengths  
A.2.1 Semi -rigid steel tape measures in a case  
A.2.1.1 Nominal length  
These measures have nominal lengths between 0.5 m and 15 m; they are of the end, line, or composite  type.  
A.2.1.2 Construction  
A.2.1.2.1 If the zero end is of a squared end type and is fitted with a ring, this ring may be included in  the 
nominal length of the measure.  
A.2.1.2.2 The means of fastening a supplementary device to the end of a measure shall be permitted to  
obscure the scale marks a t the beginning of the measure only under the following conditions:  
 if the nominal length is less than 5 m, no scale marks may be obscured;  
 if the nominal length is between 5 m and 10 m, not more than the first 15 mm may be  obscured;  and 
 if the nominal len gth is greater than 10 m, not more than the first 30 mm may be obscured.  
A.2.1.2.3 These measures may be contained in a case, one of the dimensions of which may be  included in 
the range of the scale, in particular for measurement of internal dimensions; in  this case,  the dimension in 
question shall be indicated on the case and the zero end shall be of the end type and  shall be provided with a 
fixed or sliding hook or tongue.  
A.2.1.2.4 These measures may include a belt clip or carrying strap. These must not obscure the  
dimensions marked on the side of the case or interfere with internal measurements (i.e. must not  prevent the 
end of the case touching the object being measured).  
A.2.1.2.5 The blade lock, if fitted, shall be strong enough to hold the blade at a ll extensions up to and  
including fully extended.  
A.2.1.2.6 The cross -section of the blade shall be cambered ( that is,  the blade shall be of curved 
crosssection).  
A.2.1.2.7 These tapes do not require a tractive force to be applied.  
A.2.1.3 Scale  
A.2.3.1  These measures may have two scales with the same point of origin on the same face and  may also 
have a scale on the other face.  
A.2.3.2  The scale interval shall be less than or equal to 1 cm.  
A.2.1.4 Accuracy classes  
These measures shall conform to accuracy  class I or II.  
 
 
 
 FDUS 1022 -1: 2012  
14 © UNBS  2012  – All rights reserved  
 
 
Figure A.1 — Semi -rigid steel tape measure in a case  
A.2.2  Semi -rigid steel tape measures with digital readout  
A.2.2 .1 Nominal length  
These measures have nominal lengths between 0.5 m and 15 m; they are of the end, line, or composite type.  
A.2.2 .2 Construction  
A.2.2 .2.1 If the zero end is of a squared end type and is fitted with a ring, this ring may be included in the 
nominal length of the measure.  
A.2.2 .2.2 These measures shall be contained in a case, one of the dimensions of which m ay be included 
in the range of the scale, in particular for measurement of internal dimensions; in this case, the dimension in 
question shall be indicated on the case and the zero end shall be of the end type and shall be provided with a 
fixed or sliding h ook or tongue.  
A.2.2 .2.3 The blade lock, if fitted, shall be strong enough to hold the blade at all extensions up to and 
including fully extended.  
A.2.2 .2.4 The cross -section of the blade shall be cambered (that is,  the blade shall be of curved 
crosssectio n). 
A.2.2 .2.5 These tapes do not require a tractive force to be applied.  
A.2.2 .3 Scale  
A.2.2 .3.1  These measures may have two scales with the same point of origin on the same face and may 
also have a scale on the other face. The digital readout should clea rly indicate which scale is being used.  
A.2.2 .3.2  The scale interval shall be less than or equal to 1 cm.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  15 
 A.2.2 .4 Power supply  
A.2.2 .4.1 If the indicating device is powered, the power source compartment shall form an integral part of 
the measure.  
A.2.2 .4.2 The manufacturer shall give precise rules for the replacement or recharging of the power source.  
A.2.2 .4.3  The manufacturer shall specify the maximum internal impedance of the power source.  
A.2.2 .5 Accuracy classes  
These measures shall conform to accura cy class I or II.  
 
Figure A.2 — Semi -rigid steel tape measure in a case with digital readout  
A.2.3  One-piece rigid or semi -rigid measures  
A.2.3 .1 Nominal length  
These measures have nominal lengths between 0.5 m and 5 m; they are of the end, line, or compo site type.  
A.2.3 .2 Construction  
A.2.3 .2.1 These measures are made of metal or other suitable materials.  
A.2.3 .2.2 If the zero scale mark of a dipstick is its end, this end shall be provided with an impact and  wear resistant heel 
or tip made of a material n ot liable to cause sparking on impact .  
NOTE: One -piece rigid or semi -rigid measures include dipsticks or gauge rods used for gauging the level of liquids in 
tanks used as measuring containers . 
A.2.3 .3 Scale  
These measures may have a scale on each of the t wo faces.  
A.2.3 .4 Accuracy classes  
These measures shall conform to accuracy class I or II.  
 FDUS 1022 -1: 2012  
16 © UNBS  2012  – All rights reserved  
 
 
Figure A.3 — One-piece rigid or semi -rigid measure  
A.2.4  Flexible tape measures made of fibreglass and plastics or other suitable non -metallic 
materials, not in a  case  
A.2.4 .1 Nominal length  
These measures have nominal lengths between 0.5 m and 5 m; they are of the end, line, or composite type.  
A.2.4 .2 Construction  
A.2.4 .2.1 The free ends of end or composite measures shall be provided with wear -resistant bands or t ips 
which are firmly attached to the tape.  
A.2.4 .2.2 On end measures, one end may be fitted with a ring, which may be included in the nominal length 
of the measure.  
A.2.4 .2.3 The specified tension shall be approximately 10 N to 20 N, and shall be indicated  on the 
measure.  
A.2.4 .2.4 On line measures, the zero scale mark shall be located at a distance of at least 20 mm from the 
nearest end of the measure, if the latter is not fitted with a ring, or from the outer edge of the ring, if it is fitted 
with a ring.  
A.2.4 .3 Accuracy classes  
These measures shall conform to accuracy class I, II or III.  
 
 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  17 
 
 
Figure A.4 — Flexible tape measure made of fiberglass and plastics or other suitable non -metallic 
materials  
A.2.5  Folding measures made of metal or other materials  
A.2.5 .1 Nominal length  
These measures have nominal lengths between 0.5 m and 5 m; they are of the end type.  
A.2.5 .2 Construction  
A.2.5 .2.1 All parts which are jointed at both ends shall have the same length between their jointing axes.  
A.2.5 .2.2 Jointing a nd alignment of the unfolded measure shall be ensured by an effective device. Any 
errors, positive or negative, introduced by this device shall not exceed  
 0.3 mm for measures of class II, and 
 0.5 mm for measures of class III.  
These errors are irrespectiv e of the number of joints and are in addition to the maximum permissible errors 
detailed in 4 .1.2. 
A.2.5 .3 Scale  
These measures may have a scale on each of the two faces.  
A.2.5 .4 Accuracy classes  
These measures shall conform to accuracy class II or III.  
NOTE Screw -assembly type jointed measures also exist. For this type of measure accuracy class I is admissible.  
 FDUS 1022 -1: 2012  
18 © UNBS  2012  – All rights reserved  
 
 
Figure A.5 — Folding measure made of metal or other materials  
A.2.6  Telescopic measures made of metal or other materials  
A.2.6.1 Nominal length  
These measures have nominal lengths between 0.5  m and 5 m; they are of the end type.  
A.2.6.2 Construction  
A.2.6.2.1 Jointing and alignment of the unfolded measure shall be ensured by an effective device. Any 
errors, positive or negative, introduced by this  device shall not exceed  
 0.3 mm for measures of class II,  and 
 0.5 mm for measures of class III  
These errors are in addition to the maximum permissible errors detailed in 4. 1.2. 
A.2.6.2.2 These measures are made of metal or other suitable materials.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  19 
 A.2.6 .2.3 The terminal surface of the measure shall be flat and perpendicular to the longitudinal axis of the 
measure.  
A.2.6 .2.4 The end of the measure shall be provided with an impact and wear resistant heel or tip made of a 
material not liable to cause sparking  on impact.  
A.2.6.3 Scale  
A.2.6.3.1 Measures which are circular in cross -section shall have only one scale along their length.  
A.2.6.3.2 Measures which are rectangular in cross -section may have a scale on each of the two faces.  
A.2.6 .4 Accuracy classes  
These measures shall conform to accuracy class II or III.  
A.2.7  Telescopic measures made of metal or other materials with digital readout  
A.2.7 .1 Nominal length  
These measures have nominal lengths between 0.5 m and 5 m; they are of the end type.  
A.2.7 .2 Const ruction  
A.2.7 .2.1 Jointing and alignment of the unfolded measure shall be ensured by an effective device. Any 
errors, positive or negative, introduced by this device shall not exceed  
 0.3 mm for measures of class II,  and 
 0.5 mm for measures of class III.  
These errors are in addition to the maximum permissible errors detailed in 4. 1.2. 
A.2.7 .2.2 These measures are made of metal or other suitable materials.  
A.2.7 .2.3 The terminal surface of the measure shall be flat and perpendicular to the longitudinal axis o f the 
measure.   
A.2.7 .2.4 The end of the measure shall be provided with an impact and wear resistant heel or tip 
made of a material not liable to cause sparking on impact.  
A.2.7 .3 Scale  
A.2.7 .3.1 Measures which are circular in cross -section shall have only  one scale along their length.  
A.2.7 .3.2 Measures which are rectangular in cross -section may have a scale on each of the two faces.  
A.2.7 .4 Accuracy classes  
These measures shall conform to accuracy class II or III.  
A.2.7 .5 Power supply  
A.2.7 .5.1 If the dig ital readout is powered, the power source compartment shall form an integral part of  the 
measure.  FDUS 1022 -1: 2012  
20 © UNBS  2012  – All rights reserved  
 A.2.7 .5.2 The manufacturer shall give precise rules for the replacement or recharging of the power  source.  
A.2.7 .5.3 The manufacturer shall specify the maximu m internal impedance of the power source . 
A.3 Measures for long lengths  
A.3.1 Flexible steel tape measures with winding device not designed for measuring lengths 
greater than their nominal length by repeated use of the same tape  
A.3.1.1 Nominal length  
Thes e measures have nominal lengths between 5 m and 200 m; they are of the line or composite type.  
A.3.1.2 Construction  
A.3.1 .2.1 For measures in class I, the free end shall be provided with a handle or ring, which is not included 
in the nominal length.  
For me asures in class II, the free end shall be provided with a handle or ring which may be included in the 
nominal length; in this case, the beginning of the scale shall be clearly indicated.  
A.3.1.2 .2 The means of fastening a supplementary device to the end of  a measure shall be permitted to 
obscure the scale marks at the beginning of the measure only under the following conditions:  
 if the nominal length is between 5 m and 10 m, not more than the first 15 mm may be obscured;  and 
 if the nominal length is greater  than 10 m, not more than the first 30 mm may be obscured.  
A.3.1. 2.3 These measures may include a belt clip or carrying strap, which shall neither obscure the 
dimensions marked on the side of the case nor interfere with internal measurements ( that is,  they shall not 
prevent the end of the case from touching the object being measured).  
A.3.1 .2.4 The specified tension shall be approximately 50 N or greater, and shall be indicated on the 
measure.  
A.3.1 .3 Scale  
A.3.1 .3.1 These measures may have a scale on each of the two faces.  
A.3.1 .3.2 The reference temperature, if other than 20 °C, shall be indicated on the measure (see 5.2). 
A.3.1 .4 Accuracy classes  
These measures shall conform to accuracy class I or II.  
 
 
 
 
 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  21 
 
 
Winding device case  
 
Handle type winding devi ce 
Figure A.6 — Flexible steel tape measures with winding device  
A.3.2 Flexible steel tape measures with tensioning weight or sinker  
A.3.2.1 Nominal length  
These measures have nominal lengths between 5 m and 50 m; they are of the composite type.  FDUS 1022 -1: 2012  
22 © UNBS  2012  – All rights reserved  
 A.3.2.2 Reference conditions  
The tension is approximately equal to the weight of the sinker in air. The mass of the sinker shall be  indicated 
to within ±10 g, on both the measure and the sinker.  
A.3.2.3 Construction  
A.3.2 .3.1 The sinker shall have a sufficient mass to stretch out the tape properly and shall be made of a 
material not liable to cause sparking on impact.  
A.3.2 .3.2 The sinker may be detachable or permanently attached to the tape.  
A.3.2 .3.3 This attachment or joint shall be such that additional measuremen t uncertainty is minimized.  
A.3.2 .3.4 The other end of the measure may be provided with a winding device.   
NOTE  Flexible steel tape measures with tensioning weight or sinker are frequently referred to as “oil gauging  tapes” 
or “dip tapes” and are used for gauging the level of liq uids in tanks used as measuring containers.  
A.3.2.4 Scale  
The scale shall be regular, with a scale interval of 1 mm. The base of the sinker constitutes the  principal scale 
mark at the zero end of the scale. The scale starts on a fla t face of the sinker and  continues along the entire 
length of the tape.  
A.3.2.5 Accuracy classes  
These measures shall conform to accuracy class I or II.  
However, for any length between any two scale marks, one of which is on the sinker and the other on  the 
tape, the maximum permissible error is ±  0.6 mm when application of the formula in 4. 1.2.1 gives  a value less 
than 0.6 mm.  
 
 
 
 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  23 
 
 
Figure A.7 — Flexible steel tape measures with tensioning weight or sinker  
A.3.3 Flexible steel tape measures with tensioning  weight or sinker equipped with electronic 
sensing  
A.3.3.1 Nominal length  
These measures have nominal lengths between 5 m and 50 m; they are of the composite type.  
A.3.3.2 Reference conditions  
The tension is approximately equal to the weight of the sinker in air. The mass of the sinker shall be  indicated 
to within ±10 g, on both measure and sinker.  
A.3.3.3 Construction  
A.3.3.3.1  The sinker shall have a sufficient mass to stretch out the tape properly and shall be made of  a 
material not liable to cause spar king on impact.  
A.3.3.3.2  The sinker shall be permanently attached to the tape. This attachment or joint shall be such  that 
it does not introduce any uncertainty of measurement.  FDUS 1022 -1: 2012  
24 © UNBS  2012  – All rights reserved  
 A.3.3.3.3  The other end of the measure may be provided with a winding device .  
NOTE  Flexible steel tape measures with tensioning weight or sinker equipped with electronic sensing are 
frequently referred to as “oil gauging tapes” or “dip tapes” and are used for gauging the oil -water interface and 
the level of liquids in tanks.  
A.3.3.4 Scale  
The scale shall be regular, with a scale interval of 1 mm. The sinker incorporates electronic sensing to  
determine the interface and this constitutes the principal scale mark at the zero end of the scale. The  scale 
continues along the entire leng th of the tape.  
A.3.3.5 Sensing element   
The sensing element of the measure shall provide a clear and reliable indication of the air/oil and  oil/water 
phase transition.  
A.3.3.6 Power supply  
A.3.3.6.1 If the measure is powered by a replaceable or rechargeab le battery, the battery compartment  
shall form an integral part of the measure.  
A.3.3.6.2 The manufacturer shall give precise rules for the replacement or recharging of the power  source.  
A.3.3.7 Accuracy classes  
The blades shall conform to accuracy class I  or II, as specified in 4. 1.2 and 4 .1.3. 
However, with the electronic sensor fitted, the instrument shall conform to the accuracy classes and  maximum 
permissible errors . 
A.3.4 Flexible steel surveyor's tapes designed for measuring lengths greater than  their 
nominal length by repeated use of the same tape  
A.3.4.1 Nominal length  
These measures have nominal lengths of 5 m, 10 m, 20 m, 50 m, 100 m, or 200 m; they are of the end  or line 
type.  
A.3.4.2 Reference conditions  
The specified tension shall be approximat ely 50 N or greater, and shall be indicated on the measure.  
A.3.4.3 Construction  
These measures are provided with handles or rings at both ends. If the handles are included in the  nominal 
length of the measure, they shall be so constructed that their attac hment to the tape introduces  no uncertainty 
of measurement.  
A.3.4.4 Accuracy classes  
These measures shall conform to accuracy class I or II.  
 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  25 
 
 
Figure A. 8 — Flexible steel surveyor’s tape  
A.3.5 Flexible tape measures made of fibreglass and plastics or ot her suitable nonmetallic  
materials  
A.3.5.1 Nominal length  
These measures have nominal lengths between 5 m and 100 m; they are of the end, line, or composite  type.  
A.3.5.2 Construction  
A.3.5.2.1  The ends of end measures and the zero end of composite measure s shall be provided with  wear -
resistant bands or tips which are firmly attached to the tape.  
A.3.5.2.2  For measures in class I, the free end may be provided with a ring, which is not included in  the 
nominal length.  
For measures in classes II and III, the f ree end may be provided with a ring which may be included in  the 
nominal length; in this case, the beginning of the scale shall be clearly indicated.  
A.3.5.2.3  The means of fastening a supplementary device to the end of a measure shall be permitted to  
obsc ure the scale marks at the beginning of the measure only under the following conditions:  
 if the nominal length is between 5 m and 10 m, not more than the first 15 mm may be  obscured;  and 
 if the nominal length is greater than 10 m, not more than the first 3 0 mm may be obscured.  
A.3.5.2.4  These measures may include a belt clip or carrying strap, which shall neither obscure the  
dimensions marked on the side of the case nor interfere with internal measurements ( that is,  they shall not 
prevent the end of the cas e from touching the object being measured).  
A.3.5.2.5  The specified tension shall be approximately 10 N to 20 N, and shall be indicated on the  
measure.  FDUS 1022 -1: 2012  
26 © UNBS  2012  – All rights reserved  
 A.3.5.3 Scale  
These measures may have a scale on each of the two faces.  
A.3.5.4 Accuracy classes  
These m easures shall conform to accuracy classes I, II or III.  
 
 
Winding device case  
 
Figure A.9 — Flexible tape measure  
 
 
 FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  27 
 Annex B 
(informative)  
 
Test requirements  
B.1 Test requirements for material measures of length  
B.1.1 External examination  
The object of e xamination  is to verify visually that the measure meets the requirements of this standard  with 
respect to the  design, construction and markings.  
B.1.2 Accuracy tests  
B.1.2.1 Object of the test  
This test is done t o verify that by testing that the parameters  below of the measure , the accuracy requirements 
of this standard  are met . 
B.1.2.2 Scale accuracy and large scale linearity  
B.1.2.2.1  The error in the nominal length of the measure shall not exceed the mpe given in 4. 1.2.1. 
B.1.2.2.2  The error in the dista nce between two non -consecutive marks at four randomly -chosen points  
along the length of the measure plus the nominal length shall not exceed the mpe given in 4. 1.2.1. 
The four points may also be chosen visually, seeking for errors that might be apparent b y sight.  
B.1.2.3 Scale interval accuracy  
The error in the length of the scale interval at four randomly -chosen points along the length of the  measure 
and at the nominal length shall not exceed the mpe given in 4. 1.2.2. 
B.1.2.4 Scale interval linearity  
The error in the difference between the lengths of two consecutive scale intervals at four randomlychosen  
points along the length of the measure and at the nominal length shall not exceed the mpe  given in 4. 1.2.3. 
B.1.2.5 Accuracy of other metrological compone nts, such as hooks, rings, dimensioned  tape case, 
detachable sinker  
The presence of the additional component shall not cause the error in the length of the blade to exceed  the 
mpe given in 4. 1.2.1 or the error in the length of the component, as a separate entity, shall not exceed  the 
mpe.  FDUS 1022 -1: 2012  
28 © UNBS  2012  – All rights reserved  
 B.2 Test requirements for material measures fitted with ancillary electronic devices  
B.2.1 General requirements  
This section defines the test requirements which are intended to verify that measures with ancillary  electroni c 
devices perform and function as intended in a specified environment and under specified  conditions. Each test 
indicates, where appropriate, the reference conditions for determining the  intrinsic error.  
These performance tests are additional to the accura cy tests described in B.1.2 and apply to complete  
measures or to the ancillary electronic device alone.  
The requirements assume that when the effect of one influence quantity is being evaluated, all other  influence 
quantities are maintained at the referenc e conditions.  
B.2.2 Accuracy tests for indicating devices  
B.2.2.1 Agreement with blade reading  
Throughout the length of the blade, including zero, the length indicated on the display shall meet the  
requirement in 4.2.6. 1.6. 
B.2.2.2 Hysteresis  
For changes i n blade extension of one scale interval, the length indicated on the display shall meet the  
requirement in 4.2.6.1 .6. 
B.2.3 Accuracy tests for flexible steel tape measures with tensioning weight or sinker  equipped with 
electronic sensing  
When fitted with e lectronic sensors, these instruments shall be tested according to the requirements of  the 
relevant Uganda standard.   
B.2.4 Environmental classification  
For each performance test, the severity of the test conditions is indicated. The levels correspond to t he 
climatic and electromagnetic environmental conditions to which material measures of length fitted  with 
electronic devices are usually exposed.  
B.2.5 Influence and disturbance tests for ancillary electronic devices fitted to  material 
measures of length  
Influence and disturbance tests for ancillary electronic devices fitted to material measures of length are  given 
in Table B.1 and may be carried out in any order.  FDUS 1022 -1: 2012  
© UNBS 2012  – All rights reserved  29 
 Table B.1 – Test for ancillary electronic devices for material measures of length  
Test Nature  of 
Influence  
quantity  Severity level  for the class  Applicable standards  
Static temperatures (Dry  heat, Cold)  Influence  factor  According to national  (or 
regional) legislation:  
 Dry heat  
o Severity level 1: 30 °C  
o Severity level 2: 40 °C  
o Severity level 3: 55 ° C 
o Severity level 4: 70 °C  
 Cold 
o Severity level 1: +5 °C  
o Severity level 2: –10 °C  
o Severity level 3: –25 °C  
o Severity level 4: –40 °C   
 
 
IEC 60068 -1 [1, 2]  
IEC 60068 -3-1 [3, 4]  
IEC 60068 -2-2 [5, 6, 7]  
IEC 60068 -2-1 [8, 9, 10]  
Damp heat, cyclic  (condensing)  Influence  factor  According to national  (or 
regional) legislation:  
 Severity level 1: 40 °C  
 Severity level 2: 55 °C  IEC 60068 -3-4 [11]  
IEC 60068 -2-30 [12]  
 
Mechanical shock (drop  test) Disturbance  Modified to 0.75 m drop  IEC 60068 -2-31 [13, 14]  
Immunity agai nst radiated,  radio -
frequency  
 Electromagnetic fields of  general 
origin and those  specifically 
caused by  digital radio 
telephones   
 Radiated, radio frequency,  
electromagnetic fields  
specifically caused by  digital 
radio telephones   
 
Disturbance  
 
 
Disturbance   
 
2 (E1)1) 
3 (E2)2) 
 
3 (E1)  
4 (E2)   
 
IEC 61000 -4-3 [15]  
 
 
IEC 61000 -4-3 [15]  
Electrostatic discharge  Disturbance  3 IEC 61000 -4-1 [16]  
IEC 61000 -4-2 [17]  
Voltage of power source  Disturbance  N/A OIML D11 [18]  
1) Electromagnetic disturbances corresponding to those likely to be found in residential, commercial and light industrial  buildings.  
2) Electromagnetic disturbances corresponding to those likely to be found in industrial buildings 
 
 FDUS 1022 -1: 2012  
30 © UNBS  2012  – All rights reserved  
 Bibliography  
[1] IEC Publication 60068 -1 – Ed. 6.0 (1988 -06) Environ mental testing. Part 1: General and guidance  
[2] IEC Publication 60068 -1-am1 Environmental testing. Part 1: General and guidance  – Ed. 6.0 (1992 -
06), Amendment 1   
[3] IEC Publication 60068 -3-1 Environmental testing - Part 3: Background information  – Ed. 1. 0 (1974 -01) 
- Section One: Cold and dry heat tests  
[4] IEC Publication 60068 -3-1-1A Environmental testing  - Part 3: Background information  – Ed. 1.0 (1978 -
01) First supplement  
[5] IEC Publication 60068 -2-2 Environmental testing - Part 2: Tests . Tests B: D ry heat  – Ed. 4.0 (1974 -
01). 
[6] IEC Publication 60068 -2-2-am1  Environmental testing - Part 2: Tests.  Tests B: Dry heat  – Ed. 4.0 
(1993 -02) 
[7] IEC Publication 60068 -2-2-am2 Environmental testing - Part 2: Tests . Tests B: Dry heat  – Ed. 4.0 
(1994 -05) 
[8] IEC Publication 60068 -2-1 Environmental testing - Part 2: Tests. Tests A: Cold  – Ed. 5.0 (1990 -05) 
[9] IEC Publication 60068 -2-1-am1 Environmental testing - Part 2: Tests. Tests A: Cold  – Ed. 5.0 (1993 -
02) , Amendment 1  
[10] IEC Publication 60068 -2-1-am2 Environmental testing - Part 2: Tests. Tests A: Cold  – Ed. 5.0 (1994 -
06), Amendment 2  
[11] IEC Publication 60068 -3-4 Environmental testing - Part 3 -4: Supporting – Ed. 1.0 (2001 -08)                                                                         
documentation and guidance - Damp heat tests  
[12] IEC Publication 60068 -2-30 Environmental testing - Part 2 -30: Tests - Test Db: Damp  – Ed. 3.0 (2005 -
08) heat, cyclic (12 h + 12 h cycle)  
[13] IEC 60068 -2-31 Environmental testing. Part 2: Tests. Test Ec: Drop and – Ed. 1.0 (1969 -01)                                                                       
topple, primarily for equipment -type specimens  
[14] IEC 60068 -2-31-am1 Environmental testing. Part 2: Tests. Test Ec: Drop and  – Ed. 1.0 (1982 -01), 
Amendment 1  topple, primarily for equipment -type specimens  
[15] IEC Publication 61000 -4-3 Electromagnetic compatibility (EMC) - Part 4 -3: Testing  – Ed. 3.0 (2006 -02)                                                                       
and measurement techniques - Radia ted, radio -frequency, electromagnetic field immunity test  
[16] IEC Publication 61000 -4-1 Electromagnetic compatibility (EMC) - Part 4 -1: Testing  – Ed. 2.0 (2000 -04)                                                                       
and measurement techn iques - Overview of IEC 61000 -4 series  
[17] IEC Publication 61000 -4-2 Electromagnetic compatibility (EMC) - Part 4 -2: Testing  Consol. Ed. 1.2 
(incl. am1+am2) (2001 -04) and measurement techniques - Electrostatic discharge   immunity test  
[18] OIML Internation al Document  General requirements for electronic measuring  D 11 (2004)                                                                                    
instruments  
[19] OIML International Recommendation  Automatic level gauges for measuring the level of liq uid R 85 
(1998)  in fixed storage tanks FDUS 1022 -1: 2012  
© UNBS 2012 – All rights reserved  31 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is g overned by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. Th e 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 FDUS 1022 -1: 2012    
 
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© UNBS 2 012– All rights reserved