DEAS 490:2021  
ICS 83.140.99; 97.180  
 
© EA C 2021                                                                                                                         Second  Edition  
 DRAFT EAST AFRICAN STANDARD  
Metre rules and r ulers — Specification  
EAST AFRICAN COMMUNITY  DEAS 490:2021  
ii © EAC 2021  – All rights reserved  
 Copyright notice  
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participants in the EAC standards development process is  permitted without prior permission from EAC, 
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Reproduction for sales purposes may be subject to royalty payments or a licensing agreement.  
Violators may be prosecuted . DEAS 490 :2021  
© EAC 2021  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Types  ................................ ................................ ................................ ................................ ......................  1 
4.1.1  Type 1  ................................ ................................ ................................ ................................ .....................  1 
4.1.2  Type 2  ................................ ................................ ................................ ................................ .....................  1 
4.1.3  Type 3  ................................ ................................ ................................ ................................ .....................  2 
4.2.1  Type 1  ................................ ................................ ................................ ................................ .....................  2 
4.2.3  Type 2  ................................ ................................ ................................ ................................ .....................  2 
5 Requirements  ................................ ................................ ................................ ................................ .........  2 
5.1 General Requirements  ................................ ................................ ................................ ..........................  2 
5.1.1  Tolerance  ................................ ................................ ................................ ................................ ................  2 
5.1.2  Accuracy for metre rules and rulers  ................................ ................................ ................................ .... 2 
5.1.3  Dimensions and graduation lines  ................................ ................................ ................................ ........  3 
5.1.4  Materials  ................................ ................................ ................................ ................................ .................  4 
5.1.5  Finish  ................................ ................................ ................................ ................................ ......................  4 
5.1.6  Warping and twisting  ................................ ................................ ................................ ............................  4 
5.2 Specific Requirements  ................................ ................................ ................................ ..........................  4 
6 Packaging  ................................ ................................ ................................ ................................ ...............  4 
7 Labelling  ................................ ................................ ................................ ................................ .................  5 
7 Samp ling ................................ ................................ ................................ ................................ ................  5 
Annex  A (normative)  Determination of moisture content  ................................ ................................ .............  6 
A.1 Test Specimen  ................................ ................................ ................................ ................................ ....... 6 
A.2 Procedure  ................................ ................................ ................................ ................................ ...............  6 
A.3 Calculation  ................................ ................................ ................................ ................................ .............  6 
Annex  B (Normative)  Drop test  ................................ ................................ ................................ ........................  7 
.B.1 Drop test (impact resistance)  ................................ ................................ ................................ ...............  7 
B.3.1  Procedure  ................................ ................................ ................................ ................................ ...............  7 
B.3.2   Result  ................................ ................................ ................................ ................................ .....................  7 
Annex  C (normative)  Sampling of meter rules and rulers Criteria for Conformity  ................................ ..... 8 
C.1 Scale of Sampling  ................................ ................................ ................................ ................................ .. 8 
C.2 Criteria f or Conformity  ................................ ................................ ................................ ..........................  8 
Bibliography  ................................ ................................ ................................ ................................ ........................  9 
. DEAS 490:2021  
iv © EAC 2021  – All rights reserved  
 Foreword  
Development of the East African Standards has been necessitated by the need for harmonizing requirements 
governing qualit y of products and services in the East African Community. It is envisaged that through 
harmonized standardization, trade barriers that are encountered when goods and services are exchanged 
within the Community will be removed.  
The Community has establishe d an East African Standards Committee  (EASC)  mandated to develop and 
issue East African Standards  (EAS) . The Committee is composed of representatives of the National 
Standards Bodies in Partner States, together with the representatives from the public and private sector 
organizations  in the community .  
East African Standards are developed through  Technical Committees that are representative of key 
stakeholders including government, academia, consumer groups, private sector and other interested parties. 
Draft East African Standards are circulated to stakeholders through the National Standards Bodies in the 
Partner States. The comments received are discussed and incorporated before finalization of standards, in 
accordance with the Principles and procedures for  development of East African Standards. XXXXXX.  
East African Standards are subject to review, to keep pace with technological advances. Users of the East 
African Standards are therefore expected to ensure that they always have the latest versions of the st andards 
they are implementing .  
The committee responsible for this document is Technical Committee EASC/TC 079, [name of committee]  
Attention is drawn to the possibility that some of the elements of this document may be subject of patent 
rights. EAC shall not be held responsible for identifying any or all such patent rights.  
This second edition cancels and replaces the first edition ( EAS 490:2008 ), which has been technically revised . 
 DRAFT EAST AFRICAN STANDARD  DEAS 490:2021  
 
© EAC 2021 – All rights reserved  1 
 Metre rules and rulers — Specification  
1 Scope   
This Draft East African  Standard specifies requirements , sampling and test methods  for metre rules and rulers 
for general use.  
2 Normative references   
There are no normative references in this document.  
3 Terms and definitions   
For the purposes of this document, the follow ing term s and definitions apply. ISO and IEC maintain 
terminological databases for use in standardization at the following addresses: — ISO Online browsing 
platform: available at http://www.iso.org/obp  
3.1  
meter rule  
device which is used to measure length of diff erent sizes straight lines or measure distances  
3.2  
ruler  
device used in geometry, te chnical drawing, engineering, construction etc. to measure d istances or draw 
straight lines  
4 Types  
4.1 All metre rules shall be rectangular cross section and shall be of  one of the  following types:  
4.1.1 Type 1  
A metre rule 1 m  long, 25 mm wide and 5 mm thick , with the ¼, ½  and ¾ length indicated by lines across one 
face only and n o figures  indicated.  
4.1.2 Type 2  
A rule 1 m  long, 25 mm wide and 5 mm thick. G raduated and numbe red at centimetre intervals from 1 to  99 
with graduation lines running  across the  width of the rule but broken  at the centers  to take the numbering. 
With minor graduation marks at 5 mm intervals  on each  side of the rule, the figure 10 and multiple  thereof 
marked boldly, the word, ‘ cm’ hard up against  the left -hand side of the rule and with ‘1 m’  hard  up against the 
right side edge  of the rule, in line with the numbers  DEAS 490:2021  
2 © EAC 2021  – All rights reserved  
 4.1.3 Type 3  
Rule 1  m long, 25 mm wide and 5 mm thick. G raduated and numbered at 10 mm in tervals  from 10 to 990 with 
graduation  lines running across the widt h of the rule but broken  at the centers to take  the numbering, with 
graduation  marks on the lower  edge at  1 mm and 5 mm intervals. The word,’ mm,’ hard u p against the left 
hand side of the  rule, and with  1 m’ hard up against the right hand side of the rule, in line with the numbers  
Note  The application of colour to some spaces on the rules is permissible.  
4.2 All rulers  shall be rectangular cross section and shall be of one of the  followin g types:  
4.2.1 Type 1  
A ruler 300 mm long plus ends, bevelled  edges, 25 mm x 3 mm 0r 30 mm x 3 mm cross – section between 
bevels. One  edge of the rul er to be marked and numbered in  centimetre  intervals from  1 cm to 30 cm, with 
additional marking at 1 mm a nd 5 mm  interv als, with the letters  ‘cm’ in the zero mark position.  When turned  
end for end, the other side of the  ruler shall be marked at 10 mm  intervals from 10 mm to 300 mm with 
additional  markings at  5 mm intervals with the word, ‘mm’ in the zero mark  position, or marked at 1 inch 
intervals from  1 inch to 12 in ch, with additional marking 1/16, 1/8 and ½ in intervals, with the word  ‘inch’ in  the 
zero position mark.  
4.2.3 Type 2  
A ruler  150 mm long plus ends, bevelled edges, 28 mm × 3 mm or 30 mm × 3 mm  cross section  between 
bevels.  One edge of the rul er to be marked and numbered in centimetre intervals  from 1 cm  to 15 cm. 
Additional markings at 1 mm and 5 mm  turned end for e nd. T he other ed ge of the ruler shall be marked 
similarly  or numbered at 10 mm intervals from 10 mm to 150 m m. Additional  markings at 5 mm intervals with 
the word  ‘mm’ in the zero mark position or marked and numbered at  1 inch intervals  from 1 inch to 6 inch with 
the word  ‘inch’ in the zero position mark.  
5 Requirements  
5.1 General Requirements  
5.1.1 Tolerance  
Rulers shall have the following dimensional tolerance for the width, central and bevel thickness:  
a) Plastic  rulers; printing on the top width, ±1 mm , central thickness above 2.5 mm, bevel thickness, 1 
mm to 2 mm.  
b) Plastic rulers ; printing underneath w idth, ± 1mm. central thickness , above 2.5 mm, b evel thickness, 1 
mm to 2 mm.  
c) Wooden rulers; w idth, ± 1 mm. central thickness, 4 mm minimum, b evel thickness, 2.5 ± 0.5 mm.  
5.1.2 Accuracy  for metre r ules and rulers   
5.1.2 .1 The degree of accuracy of the straightness of the edges shall be within 0.25 mm in 300 mm.  
5.1.2 .2 The degree of accuracy of the spacing of the m arkings shall be within 0.75 mm  in 300 mm, and 
within 0.25 mm in any 25 mm of length.                      DEAS 490:2021  
© EAC 2021  – All rights reserved  3 
 5.1.3 Dimensions and graduation  lines  
5.1.3 .1 The dimensions shall  be as given in Figure 1. The length  from the edge inwards of the lines 
where not taken fully, across the face shall be approximately as shown in figure  1. 
 
 
Figure 1 ─ Dimensions for meter rules and rulers  
5.1.3 .2 The lines shall be such as to give clarity in reading and enable the different lengths of line to be 
easily distinguished. Table 1 is an approximate guide.  
DEAS 490:2021  
4 © EAC 2021  – All rights reserved  
 5.1.3 .3 The graduation lines shall be of contrastin g colour  from that of the base material.  
Table 1 ─ Length of graduation lines  
Type of line  Length of line on rule or ruler  
 Minimum 
(mm)  Maximum (mm)  
1 3 4.75 
5 4 5.5 
10 4 7 
 
5.1.4 Materials   
5.1.4.1 Metre rules and rulers shall be made of wood, plast ic, metal or other suitable materials of 
adequate rigidity and shall be free from embrittlement.  
5.1.4.2 The finished metre rules and rulers shall be flat and shall remain flat under normal use.  
5.1.4.3 They shall not be highly flammable  and toxic.  
5.1.4.4 The metre rules and rulers shall not have sharp edges which may be injurious to the user  
5.1.5 Finish  
The finish for the metre rule or ruler shall be free from any defects that might affect its serviceability.  
5.1.6 Warping and twisting   
A rule or rul er shall show no signs of twisting or warping that would render it unusable after being conditioned 
for 48 hours in an atmosphere of 80 pe r cent relative humidity at 20 ˚C.  
5.2 Specific Requirements  
The meter rules and rulers  shall comply with t he requirem ents given in Table 2  when tested in accordance 
with the methods prescribed therein.  
Table 2 ─ Specific requirements for meter rules and rulers  
Parameter  Requirement  Test method  
Moisture content 
(wooden), %v/v, max  10 Annex A  
Drop test  remain intact  Anne x B 
 
6 Packaging  
Each meter rule or ruler shall be individually packed in suitable packages to avoid any breakage or scratches 
during storage and transportation.                      DEAS 490:2021  
© EAC 2021  – All rights reserved  5 
 7 Labelling  
Each metre rule or ruler  shall be legibly and indelibly labelled in English and/ or any o ther official language 
(French, Kiswahili, etc.) used in the importing East African Partner State with the following information:  
a) Manufacturer’s name and address  
b) Registered Trademark if any  
c) Country of manufacture/origin  
d) Batch number  
7 Sampling  
Samp ling shall be done in accordance with Annex C  DEAS 490:2021  
6 © EAC 2021  – All rights reserved  
 Annex  A 
(normative)  
 
Determination of moisture content  
A.1 Test Specimen  
The entire wooden meter rule or ruler may form the test specimen for the determination of moisture content or 
a piece  cut from it. When f or any reason, additional determination of moisture content is required, separa te 
samples shall be prepared from  the sample material used in preparing the test specimens. Smaller specimens 
may be used when deemed necessary. The test shall be carried out im mediately after cutting the specimen  
A.2 Procedure  
Weigh accurately each test specimen and dry in a ventilated oven at a temperature of 105 °C ± 2 °C until the 
mass becomes constant between two successive weighing made at an interval of not less than one h our 
A.3 Calculation  
 
Where:  
W1  initial mass in grams of test specimen, and  
W0 oven -dry mass in grams of the test specimen  
                    DEAS 490:2021  
© EAC 2021  – All rights reserved  7 
 Annex  B 
(Normative ) 
 
Drop test  
.B.1 Drop test (impact  resistance)  
B.3.1  Procedure  
B.3.1.1  The meter rule or ruler without any packaging is dropped from a height of 0.9 to 1.2 m  
B.3.1.2  This is repeated three more times  
B.3.2   Result  
The product must remain intact  
 DEAS 490:2021  
8 © EAC 2021  – All rights reserved  
 Annex  C 
(normative)  
 
Sampling of meter rules  and rulers Criteria for Conformity  
C.1 Scale of Sampling  
C.1.1  Lot – In any consignme nt, all meter rules and rulers of the same size, material and shall constitute a 
lot. Care shall  be taken to ensure that meter rules or rulers  included in a lot do not di ffer in construction as far 
as possible  
C.1.2  The conformity of the meter rules or rulers  in a lot to the requirements of this specification shall be 
ascertained for each lot separately. The number of meter rules or rulers  to be selected for this purpose s hall 
be in accordance with col. 1 and co l. 2 of Table C1  
C.1.3  The meter rules or rulers shall be selected at random. To ensure randomness of selection one of the 
following procedures is recommended for use:  
a) If all the meter rules or rulers in a lot are pa cked in one b ox, then starting from any metre rule or ruler , 
count them in any suitable order as 1, 2, …… up to r and so on, where r is the integral part of N/n (N 
and n being the lot size and sample size respectively). Every r th meter rule or ruler  thus counted shall 
be withdrawn to constitute the sample.  
b) If the meter rules or rulers  in a lot are packed in more than one box, approximately equal number of 
meter rules or rulers  shall be picked up at random from as many boxes as possible so as to obtain the 
required number of meter rules or rulers  as specified in Table C1 . 
Table C1  — Scale of Sampling  
No. of meter rules or rulers in a 
lot 
N No. of meter rules or rulers to be 
selected  
n 
Up to 10  2 
11 to 25 3 
26 to 50  4 
51 to 100  6 
101 to 150  6 
151 to 300  7 
301 to 500  8 
501 and Above  10 
 
C.2 Criteria for Conformity  
For declaring the conformity of the lot to the requirements of this specification, all the meter rules or rulers  
selected according to C.1.3 shall satisfy the relevan t requirements given in clause 5, 6 and 7                      DEAS 490:2021  
© EAC 2021  – All rights reserved  9 
 Bibliography  
[1] EAS 490:2008,  Metre rules and rulers for school and office use — Specification  
[2] TZS 1006: 2011 , Metre rules and rulers for the school and office use – Specification  
 DEAS 490:2021    
 
© EAC  2021  – All rights reserved