DRAFT UGANDA STANDARD ON PUBLIC REVIEW       DRAFT UGANDA 
STANDARD  
    DUS EAS 357 
First  Edition  
2015-mm-dd 
 
 Reference number  
  DUS EAS 3 57: 2004 
© UNBS 201 5 
  
Pneumatic tyres for trucks and buses — Specification 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWDUS EAS 3 57:20 04 
ii                © UNBS 2015 - 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 2015 
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 photocopying 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 41 505 995 
Fax: 256 41 286 123 
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEW DUS EAS 3 57:20 04 
© UNBS  2015 - All rights reserved                iii National foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amended.  UNBS is mandated to co-
ordinate the elaboration of standards and is  
(a) a member of International 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 Agreement of the World Trade Organisation (WTO). 
The work of preparing Uganda 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 stakeholders. 
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 Draft Uganda Standard, DUS EAS 3 57: 2004 , Pneumatic tyres for trucks and buses — 
Specification , is identi cal with  and has been reproduced from an East African  Standard , EAS 357: 2004 , 
Pneumatic tyres for trucks and buses — Specification , and is being proposed for adoption  as a Uganda 
Standard.  
This standard cancels and replaces US 514:2004, Specification for new pneumatic tyres — Trucks and buses . 
This Uganda Standard, DUS EAS 3 57: 2004 , has been developed by the Transport and communication 
standards Technical Committee (UNBS/TC 8).  
Wherever the words, “ East African Standard" appear, they should be replaced by "Uganda Standard." 
 
  DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004 
ICS 83.160.10 
HS 4012.20; 
HS 4012.20.10 (radial) 
 HS 4012.20.90 (other) 
© EAC 2004                                                                                                      First Edition 2 004  
 
 
 
 
 
EAST AFRICAN STANDARD 
 
 
Pneumatic tyres for truck s and buses — Specification  
 
 
 
  
 
  
 
  
 
  
 
  
 
 
  
 
 
  
 
  
 
  
 
  
EAST AFRICAN COMMUNITY  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWDRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                    
Foreword 
 
Development of the East African Standards has been necessitated by the need for harmonizing 
requirements governing quality of products and services in East Africa. It is envisaged that through 
harmonized standardization, trade barriers which are encountered when goods and services are 
exchanged within the Community will be removed.  
In order to achieve this objective, the Partner States in the Community through their National Bureaux 
of Standards, have established an East African Standards Committee.  
The committee is composed of representatives of the National Standards Bodies in Partner States, 
together with the representatives from the private sectors and consumer organizations. 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 procedures of the Community.  
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 standards they are implementing.  
 
© East African Community 2004 — All rights reserved
* 
East African Community  
P O Box 1096  
Arusha  
Tanzania  Tel: 255 27 2504253/8 Fax: 255-27-2504481/2504255 
E-Mail: eac@eachq.org Web: www.each.org 
 
                                                 
* © 2004 EAC — All rights of exploitation in any form and by any means reserved worldwide for EAC Partner States’ NSBs.  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
2                                                                                            © EAC 2004 — All rights reserved  
Contents 
 
1 Scope ........................................................................................................................ .................. 1 
2 Application .................................................................................................................. ................. 1 
3 References ................................................................................................................... ............... 1 
4 Terminology.................................................................................................................. ............... 1 
5 General requirements ......................................................................................................... ......... 1 
6 Tyre designation ............................................................................................................. ............. 2 
7 Tyre dimensions .............................................................................................................. ............ 3 
8 Tyre dimension tables........................................................................................................ .......... 5 
9 Load ratings................................................................................................................. ................ 5 
10 Test requirements............................... ..................................................................................... 7 
11 Nonconforming tyres ......................................................................................................... ...... 9 
Annex A (informative)  Guideline values for metr ic series, 5° rims ..................................................... 15 
Annex B (informative)  Guideline values for me tric series, 15° rims ..... .............................................. 18 
Annex C (informative)  Tyre dimension ta bles ................................................................................... .2 0  
Annex D (informative)  Test conditions for ty res with non-standard marking ...................................... 21 
 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                    
Introduction  
 
This East African Standard has been prepared in order to give the necessary specifications and requirements for test of pneumatic tyres.  It provides important information to be observed for 
improvement of motor vehicle safety in the country. 
 In reporting the results of a test made in accordance with this East African Standard, if the final value 
observed or calculated is to be rounded off, it shall be done in accordance with EAS 124, 
Rounding 
off numerical values . 
 In the preparation of this East African Standard, assistance was derived from the following 
documents: 
 BS AU 50-1.2.1a:1995, 
Tyres and wheels — Specification for metric series tyres — Commercial 
vehicle tyres,  published by the British Standards Institution. 
 ISO 4209-1:2001, 
Truck and bus tyres and rims (metric series) — Part 1: Tyres  
 ISO 10454:1993(E), 
Truck and bus tyres — Verifying tyre capabilities — Laboratory test methods , 
published by the International Organization for Standardization.  
 
Some company standards from our local industries. 
 
Acknowledgement is hereby made for the assistance derived from these sources. 
 
 
 
 
 
  
 
  
 
 
 
  
 
 
 
  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWDRAFT UGANDA STANDARD ON PUBLIC REVIEW 
 
EAST AFRICAN STANDARD                                          EAS 357:2004 
 
 
© EAC 2004 — All rights reserved                                                                                              1  Pneumatic tyres for truck s and buses — Specification 
 
1 Scope  
This East African Standard specifies tyre dimensions designation and marking requirements; and load 
ratings.  It also gives laboratory test requirements for strength endurance for tyres primarily intended 
for trucks and buses.  
2 Application  
 
This standard applies to new pneumatic tyres bias-belted, diagonal and radial mounted on 5° tapered 
rims and on 15° tapered (drop-centre) rims for use on trucks and buses. It does not apply to any tyre 
which has been reconditioned; or to any tyre which has been altered so as to render impossible its use, or its repair for use, as  motor vehicle equipment.  
3 References  
 
This East African Standard makes reference to the following documents: 
 
EAS 124, Rounding off numerical values 
 
EAS 53, Tyre reconditioning — Specification   
 
EAS 358, Pneumatic tyres for passenger cars — Specification   
 
4 Terminology   
 
For the purpose of this standard, the definitions given in EAS 53 and EAS 358 shall apply. 
 
5 General requirements 
 
5.1 Materials   
 
The basic compound used in the tyre construction shall be of natural rubber,  synthetic rubber, or a 
combination thereof. 
 
5.2 Retread ability  
 The tyre construction shall be of a type that allows for retreading to the tyre casing. 
 
5.3 Ozone resistance   
 
Each tyre as part of production shall contain sufficient anti-oxidants and anti-ozonants to provide 
standard commercial resistance to weathering. 
 
5.4 Temperature ability  
 Each tyre shall have an inherent capability of a cceptable performance in ambient air temperatures 
ranging from 49 °C to – 40 °C. 
 
5.5 Workmanship   
 
A tyre covered under this specification shall show no evidence of poor workmanship. All plies, belts, 
bead, and breakers shall be smooth and evenly laid and shall be free of buckles, wavy cord, air 
pockets and any other anomalies or imperfections, which may impair serviceability. DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
2                                                                                            © EAC 2004 — All rights reserved  
5.6 Age of rubber  
 
Tyre covered under this specification shall not be more than 8 years from the date of manufacture.  
 
6 Tyre designation  
 
The designation of the tyre shall be shown on its sidewall and shall include the following markings, to 
be shown close to each to other: 
 
a) size and construction; and 
b) service condition characteristics. 
 
6.1 Size and construction  
 
The size and construction shall be indicated as follows: 
 Nominal   Nominal   Tyre    Nominal  
section   aspect  construction  rim diameter  
width    ratio    code    code  
or  
Nominal   Nominal   Tyre    Nominal  section   aspect  construction  rim  
width    ratio    code    diameter 
 
6.1.1  Nominal section width  
 
The nominal section width shall be expressed in millimetres (or equivalently in inches).  For tyres fitted to 5° taper rims and 15° taper rims (code- designated), the nominal tyre section width shall end in 5. 
 
6.1.2    Nominal aspect ratio  
 The nominal aspect ratio shall be expressed as a percentage and shall be a multiple of 5. 
 
6.1.3  Tyre construction code  
 The tyre construction code shall be as follows: 
 
B for bias – belted construction  
 
D l – for diagonal/bias construction  
 
R for radial construction  
 
6.1.4  Nominal rim diameter  
 
The nominal rim diameter shall be expressed by a code for 5° tapered bead seat rims and 15 ° 
tapered bead seat (drop–centre rims (see table 1 for code correlations). 
 
6.2  Service condition characteristics  
 The characteristics shall be indicated as follows;   
Load index  / Load index   Speed symbol single  / dual   
Load index 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            3  The load index is a numerical code associated with maximum load a tyre can carry at the speed 
indicated by its speed symbol under the service conditions specified by the tyre manufacturer.  
 
6.3 Other service characteristics 
  
6.3.1  The word “ TUBELESS ” shall appear on the tyre to characterize  tyres that can be used without 
a tube.   
 
6.3.2  An arrow to indicate direction of rotation if preferred.   
 
6.3.3  In case of special tread tyres the symbol “ EY” shall be shown on the tyre. 
 
6.3.4    Each tyre shall be labeled with the name of manufacturer/brand name and recognized 
quality/safety mark to show that the tyre conforms to respective national standards.  The tyre may be 
also be marked with any other identification assigned to the manufacturer.  
6.4 Example  
 A tyre having  
 
a) A size and construction of : 
 
i) nominal section width  275 mm, 
 
ii) nominal aspect ratio 70 %, 
 
iii) radial construction, 
 
iv) nominal rim diameter code 22.5,  
 
b) Service condition characteristic of : 
 
i) single load 2 500 kg, 
 
ii)  dual load 2 300 kg, 
 
iii) reference speed 130 km/h, 
 
c) other service characteristics  
 
i) tubeless, 
 
ii) special tread, 
 
shall be marked 
 
 
  EY           
 
 275/70 R 22.5     I 1440/137 M    
 
        TUBELESS 
 
7 Tyre dimensions  
 
7.1 Calculation  “of design tyre” dimensions   
 
For the choice of coefficients K,  (rim section ratio) and K2 (see Table 2). 
 
7.1.1  Theoretical rim width , Rth 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
4                                                                                            © EAC 2004 — All rights reserved The theoretical rim width, Rth ,  is equal to the product of the nominal section width , SN and the 
rim/section ration K1, Rth  =  K 1 SN. 
 
7.1.2  Measuring rim width  Rm 
 
The measuring rim width, Rm is the width of the existing rim nearest to the theoretical rim width, R th 
(see table 3) for the rim widths of 5° tapered and 15° tapered (drop-center) rims.  
7.1.3  Design tyre section width, S   
 The design tyre section width, 
S is the nominal section width, SN transferred from the theoretical rim, 
Rth to the measuring rim, Rm. 
 
S = SN + K 2 (Rm – Rth) 
 
Rounded to the nearest whole number. 
 
7.1.4  Design tyre section height , H 
 
The design section height, H is equal to the product of the nominal section width, SN and the nominal 
ratio H/S (H/S  as %)  
 
100HNS H S/=  
 
Rounded to the nearest whole number. 
 
7.1.5  Design tyre overall diameter, D o 
 
The design tyre overall diameter, Do is the sum of the nominal rim diameter, Dr, plus twice the design 
tyre section height. 
 
 Do = D r + 2H 
 
For those tyres using a nominal rim diameter code, see table 1 (a) for the value of Dr, to be used  
 
7.1.6  Values   
 
The relevant dimensions for the metric series of truck and bus tyre measuring rim width, design 
section width and design section height are shown in annexes A and B for tyres of a given series, with a nominal tyre section over 205, it is recommended that they should be in increments larger than 10. 
 
7.2 Calculation of “maximum overall tyre dimensions in service”   
 
These calculations are for use by vehicle manufacturers in designing for tyre clearances. 
 
7.2.1  Maximum overall width in service , W max.    
 The maximum overall width in service, 
W max is equal to the product of the design section width, S, 
and the appropriate coefficient, a (see Table 2). 
 
W max. =Sa  
 It includes protective ribs, lettering, embellishments, manufacturing tolerances and growth due to 
service. 
 
7.2.2  Maximum  overall diameter in service,  Do,  max. 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            5  The maximum overall diameter in service, Do max is equal to the nominal diameter, Dr, plus twice the 
product of the design tyre section height, H and the appropriate coefficient, b (see Table 2). 
 
D o max = Dr  + 2 Hb 
 
It includes manufacturing tolerances, the different tyres of tread patterns and growth due to service.  
 
7.3 Minimum dual spacing (MDS)  
 
7.3.1 The minimum dual spacing is a guideline value equal to the product of the design tyre section 
width, S, and appropriate coefficient K3 (see Table 2b). 
  
 MDS  = SK 3 
 
It is referred to as tyre load according to the load index, in dual application shown in the service 
characteristics on the tyre at an inflation pressure applicable for normal highway service. 
 
7.3.2 The design tyre section width, S, will change 2.5 mm for each 0.25 change in rim width code.  
The minimum dual spacing shall be adjusted accordingly. 
 
7.4 Permitted rim widths 
 The range of permitted rim widths, in millimetres is determined for each nominal section width, by 
multiplying the nominal section width, 
SN by the coefficients CR, presented in  
Table 3. 
 
i.e.   
minimum rim width: 
CR min. x SN  
 
 maximum rim width : CR max. SN 
 
8 Tyre dimension tables  
 
Example of few  sizes in a tyre dimension table are shown in C.2   and C.3. The figures shown in the 
column headed “Rim” are codes related to measuring rim width, R m (see Table 1 (AB) for code 
correlations). 
 
9 Load ratings  
 
9.1   Tyre load – carrying capacity  
 
 See Table 4 for load indices  
 
 9.2   Speed symbols   
 See Table 5 speed symbols 
 
9.3 Load — carrying capacity at various speeds  
 
When the tyre is fitted on a vehicle with a maximum speed capability different from the tyre reference 
speed, variations of load are granted in relation to the load corresponding to the load index (Table 6).  To obtain improved operating performance under these conditions, inflation pressures higher than the 
basic pressure may be required.  DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
6                                                                                            © EAC 2004 — All rights reserved  
Table 1( A) — Nominal rim diameter code  
 
Code 
15° tapered rims 15° tapered (drop centre) rims Nominal rim diameter Dr mm. 
10 
12 
13 14 
- 
15 16 
17 
- 
18 
- 
20 
- 
22 
- 
24 
- - - 
- - 
14.5 
- - 
- 
17.5 
- 
19.5 
- 
20.5 
- 
22.5 
- 
24.5 254 305 
330 356 368 
381 
406 
432 
445 
457 
495 
508 
521 559 572 
610 
622 
 
 
Table 1( B) — Nominal rim diameter code 
 
Code 
15° tapered rims 15° tapered (drop center) rims Nominal rim diameter Dr mm. 
 
3.50 
4.00 
4.5.0 
5.00 
- 
5.50 6.00 
6.5 0 
- 
7.00 7.50 
8.00 
- 
8.50 
9.00 
9.50 
- 
10.00 
10.50 
11.25 
- - 
13.00 
14.00 15.00 
- -  
- - 
- 
- 
5.25 
- 
6.00 
- 
6.75 
- 
7.50 
- 
8.25 
- 
9.00 
- 
9.75 
- 
10.50 
- 
11.75 
12.25 
13.00 14.00 15.00 
16.00 
18.00  
88.9 
101.6 
114.3 
127 
133.5 
139.7 152.5 
165.1 
171.5 
177.8 
190.5 
203. 2 
209.5 215.9 
228. 5 
241.3 247.5 
254 
266.5 
285. 8 
298.5 
311 330 
355.5 
381 
406.5 
457 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            7   
Table 2 — Coefficients for calculation of tire dimensions 
 
a) Coefficients K2, b, a. 
Structure  Tyre construction code Coefficients 
 
Bias – belted  
 
Diagonal  
 
 Radial   
B 
 
D 
 
R  
0.4 
 
0.4 
 
0.4  
1.07 
 
1.07 
 
1.04  
1.08 
 
1.08 
 
1.05 
 
 
a) Coefficients K1, K3 
 
Tyre construction 
code Type of 
rim Nominal 
aspect 
ratio H/S Rim/section ratio 
K1 Minimum 
dual spacing K3 
 
5 ° tapered 100 to 65 0.70 1.15  
15° tapered 90 to 65 0.75 1.125 
 
 
Table 3 — Coefficients for calculation of rim wi dths for truck and bus tyres related to nominal 
aspect ratio H/S 
 
Coefficients for   calculation  of 
recommended rim width 
 
CR Type of rim  
 
 Nominal aspect 
ratio H/S  Nominal section   
width 
SN (mm) 
Min. 
 Max. 
15° tapered 65 ≤ H/S ≤ 100 
 All 0.65 0.80 
75 ≤ H/S ≤ 90 
 ≥ 225 0.675 0.80  
15° tapered 
65 ≤ H/S ≤  70 All 0.675 0.85 
 
10 Test requirements  
 
10.1 Test sample  – two tyres of identical characteristics shall comprise a test sample. 
 
a) one tyre shall  be used for the measurement of strength; and  
 
b) a second tyre for the endurance test. 
 
 
10.2 Test equipment  
 The test equipment shall constitute the following items: 
 
10.2.1  Test drum, cylindrical driven flywheel (drum)  — having a diameter of 1.7 m ± 1 % or 2 m ± 1 
%; the surface of which is made of smooth steel.  The width of the test surface shall be equal or 
greater than the overall width of the test tyre . 
 
For the test drum, the loading device may be a dead-weight cantilevered system with a hydraulic or 
pneumatic system. The accuracy shall be within ± 1.5 % of the full scale; the speed capability of the 
equipment shall be adequate for the requirements of the test methods.  The accuracy of the test drum 
speed shall be within + 2 km /h at the full scale. 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
8                                                                                            © EAC 2004 — All rights reserved 10.2.2  Plunger, cylindrical steel plunger  of sufficient length with a hemispherical end and a 
diameter as shown in Table 7 with reference to the tyre load index. 
 
For the plunger equipment, the loading device shall permit gradual application of the force.  Indicators 
of displacement and of force shall be provided with accuracy within ± 3 % of the full scale.  
10.2.3 Inflation pressure gauges , with a maximum scale value of at least 1000 kPa with accuracy 
within ± 20 kPa.  
 
10.3 Testing   
 
10.3.1  Strength test    
 
10.3.1.1  Requirement — Each test sample shall meet at least the requirements for minimum 
breaking energy specified in Table 8 when tested in accordance with 10.3.1.3 
 
10.3.1.2  Preparation of the tyre — The tyre is mount on a test rim and inflated to the pressure 
specified for the maximum load rating in single formation, or maximum dual load, when they differ. The assembly is maintained at test room temperature for at least 3 h. 
 
10.3.1.3  Test procedure — The pressure is readjusted to that specified in 10.3.1 and the assembly 
mount on a fixture.  
The plunger is positioned as near to the centreline as possible, avoiding penetration into the tread grooves; and forced perpendicularly into the tread at a rate of 50 mm/min. ± 2.5 mm/min. 
 
The force and penetration at the moment of breaking are recorded, at each of five test points approximately equally spaced around the circumference of the tyre. The pressure should be checked 
before moving to the next test point. 
  If the tyre fails to break before the plunger is stopped on reaching the rim and the required minimum 
breaking energy is not achieved, then the tyre is deemed to have passed the test at that point. 
 
The breaking energy W, in joules for each test point is computed using the following formula: 
 
2000P FW×=  
 
where  
 
F = force in Newton  
P = penetration in mm 
 The breaking energy value for the tyre is obtained by taking the average values. 
 
10.3.2  Endurance test  
 
10.3.2.1  Requirement — When the tyre has been subjected to the laboratory endurance test using 
the procedure in 10.3 2.3, using a test rim and a valve which undergo no permanent deformation and 
allows no loss of air, there shall be no visual evidence of tread, sidewall, ply cord innerliner, belt or 
bead separation, chuking, open splices, cracking or broken cords. 
 The
 tyre pressure measured immediately after the test shall not be less than the initial pressure 
specified in 10.3.2.2. 
 
10.3.2.2  Preparation of tyre  — The tyre is mount on a test rim and inflated to the pressure 
corresponding to the maximum load rating.  The tyre and rim assembly is maintained at eminent temperature, which shall be at least 20 °C, for at least 3 h. 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            9  10.3.2.3  Test procedure — The tyre pressure is readjusted to the value specified in 10.3.2.2 
immediately before testing.  Then the tyre and rim assembly is mount on a test axle so that the tyre 
may be pressed radially against the outer face of the test drum. 
 
 During the test, the ambient temperature shall be maintained at between 20 °C and 30 oC or at a 
higher temperature if the tyre manufacturer agrees. 
 
Each successive phase of the test shall be conducted without interruptions, at a test speed with loads and test periods as shown in:  
 
a) table 8a for tyres width load index (single) up to 121 inclusive and speed symbol up to 
P; 
 b) 10.3.2.4 for tyres with load index (single up to 121 inclusive and speed symbols 
Q and above;  
 c) Table 8b for tyres with load index (single) 122 and above. 
 
Throughout the test, the inflation pressure shall not be corrected and the test load shall be kept 
constant.  
10.3.2.4  Specific conditions for tyre with speed symbol Q and above — The load applied shall 
be:  
 
a) 90 % of the maximum load rating on 1.7 m drum diameter;   b) 92 % of the maximum load rating on 2 m drum diameter. 
 
The initial test speed shall be equal to the tyre's speed category minus 20 km/h.  
The equipment shall be operated in such a way that the drum speed is brought up to the initial test 
speed over a period of 10 min.  
The equipment is operated with the test drum speed at the initial test speed for 10 min, then at the 
initial speed plus 10 km/h for at least 10 min and finally at the tyre’s speed category for 30 min; the 
total duration of the test being 1 h.  
11 Nonconforming tyres  
 
No tyre that is designed and manufactured for use on buses and trucks, that does not conform to the 
requirements of this standard shall be sold, offered for sale, introduced or delivered for introduction 
into, or imported into the East Africa Community, for any purpose.  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
10                                                                                            © EAC 2004 — All rights reserved Table 4 — Correlation between load index and tyre load carrying capacity (TLCC) 
 
Load  TLCC  Load  TLCC  Load  TLCC Load  TLCC  Load  TLCC  Load  TLCC  Load  TLCC  
Index   Index   Index   Index   Index   Index   Index   
(LI)  kg  (LI)  kg  (LI)  kg  (LI)  kg  (LI)  kg  (LI)  kg  (LI)  kg  
0  46  40  140  80  450  120  1 400  160  4 500  200  14 000  240  45 000  
1  46,2  41  145  81  462  121  1 450  161  4 625  201  14 500  241  46 250  
2  47,5  42  150  82  475  122  1 500  162  4 750  202  15 000  242  47 750  
3  48,7  43  155  83  487  123  1 550  163  4 875  203  15 500  243  48 750  
4  50  44  160  84  500  124  1 600  164  5 000  204  16 000  244  50 000  
5  51,5  45  165  85  515  125  1 650  165  5 150  205  16 500  245  51 500  
6  53  46  170  86  530  126  1 700  166  5 300  206  17 000  246  53 000  
7  54,5  47  175  87  545  127  1 750  167  5 450  207  17 500  247  54 500  
8  56  48  180  88  560  128  1 800  168  5 600  208  18 000  248  56 000  
9  58  49  185  89  580  129  1 850  169  5 800  209  18 500  249  58 000  
10  60  50  190  90  600  130  1 900  170  6 000  210  19 000  250  60 000  
11  61,5  51  195  91  615  131  1 950  171  6 150  211  19 500  251  61 500  
12  63  52  200  92  630  132  2 000  172  6 300  212  20 000  252  63 000  
13  65  53  206  93  650  133  2 060  173  6 500  213  20 600  253  65 000  
14  67  54  212  94  670  134  2 120  174  6 700  214  21 200  254  67 000  
15  69  55  218  95  690  135  2 180  175  6 900  215  21 800  255  69 000  
16  71  56  224  96  710  136  2 240  176  7 100  216  22 400  256  71 000  
17  73  57  230  97  730  137  2 300  177  7 300  217  23 000  257  73 000  
18  75  58  236  98  750  138  2 360  178  7 500  218  23 600  258  75 000  
19  77,5  59  243  99  775  139  2 430  179  7 750  219  24 300  259  77 500  
20  80  60  250  100  800  140  2 500  180  8 000  220  25 000  260  80 000  
21  82,5  61  257  101  825  141  2 575  181  8 250  221  25 750  261  82 500  
22  85  62  265  102  850  142  2 650  182  8 500  222  26 500  262  85 000  
23  87,5  63  272  103  875  143  2 725  183  8 750  223  27 250  263  87 500  
24  90  64  280  104  900  144  2 800  184  9 000  224  28 000  264  90 000  
25  92,5  65  290  105  925  145  2 900  185  9 250  225  29 000  265  92 500  
26  95  66  300  106  950  146  3 000  186  9 500  226  30 000  266  95 000  
27  97,5  67  307  107  975  147  3 075  187  9 750  227  30 750  267  97 500  
28  100  68  315  108  1 000 148  3 150  188  10 000  228  31 500  268  100 000  
29  103  69  325  109  1 030 149  3 250  189  10 300  229  32 500  269  103 000  
30  106  70  335  110  1 060 150  3 350  190  10 600  230  33 500  270  106 000  
31  109  71  345  111  1 090 151  3 450  191  10 900  231  34 500  271  109 000  
32  112  72  355  112  1 120 152  3 550  192  11 200  232  35 500  272  112 000  
33  115  73  365  113  1 150 153  3 650  193  11 500  233  36 500  273  115 000  
34  118  74  375  114  1 180 154  3 750  194  11 800  234  37 500  274  118 000  
35  121  75  387  115  1 215 155  3 875  195  12 150  235  38 750  275  121 000  
36  125  76  400  116  1 250 156  4 000  196  12 500  236  40 000  276  125 000  
37  128  77  412  117  1 285 157  4 125  197  12 850  237  41 250  277  128 500  
38  132  78  425  118  1 320 158  4 250  198  13 200  238  42 500  278  132 000  
39  136  79  437  119  1 360 159  4 375  199  13 600  239  43 750  279  136 000  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            11  Table 5 — Correlation between speed symbol and speed category 
 
Speed symbol  Speed category  
 km/h  
B  50  
C  60  
D  65  
E  70  
F  80  
G  90  
J  100  
K  110  
L  120  
M  130  
N  140  
P  150  
Q  160  
R  170  
S  180  
T  190  
H  210  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
12                                                                                            © EAC 2004 — All rights reserved  
Table 6 — Load-carrying capacity at various speeds  
 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            13   
Table 7 — Plunger diameter 
 
 
Load index in single formation  
Plunger diameter 
 
≤ 121 
122 – 134 
≤ 135 
 19 
32 38 
 
Table 8 — Endurance test parameters  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
14                                                                                            © EAC 2004 — All rights reserved  
Table 9 — Minimum breaking energy 
 
 
Inflation pressure 
corresponding to maximum load rating  
KPa  
Breaking energy 
min. 
J 
 
a) Types with load index  (single) ≤ 121 
 
 Nominal rim diameter code  < 13 Nominal rim diameter code   
≥ 
 
up to 250 
250 to 350 
351 to 450 
451 to 550 551 to 650 
over 650  
136 203 
271 
- 
- 
-  
294 
362 
514 
576 644 
712 
 
b) Tyres with load index    ≥ 122 
 
 
up to 550 
551 to 650 
651 to 750 
751 to 850 851 to 950  
972 
1412 
1695 
2 0 90 
2 203 
 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            15   
Annex A 
(informative) 
 
Guideline values for metric series, 5° rims 
 
A.1 The values given in table A.1 are for information. 
 
A.2 These values will serve as a guideline for design of tyre dimensions, metric series, mounted on 
5° tapered drop-centre rims (code-designated) with nominal rim diameters up to code 16 inclusive.  
For tyres mounted on 15° tapered drop-centre rims (code-designated), see Annex B. For tyres 
mounted on deferent types of rims (millimetre-designated), other annexes will be established. 
 
Table A.1 — Dimensional guidelines for metric “100” to “75” series tyres on 5° tapered rims  
 
Tyre design dimensions, mm  
Design section height a , H  Nominal 
section 
width SN  Measuring 
rim width 
code Rm  Design 
section 
width S  Nominal aspect ratios, H/S  Approved rim 
width codes  
mm    100  95  90  85  80  75  min.  max.  
125  3.50  126  125  119  113  106  100  94  3  4  
135  3.50  133  135  128  122  115  108  101  3.5  4.5  
145  4.00  145  145  138  131  123  116  109  3.5  4.5  
155  4.50  157  155  147  140  132  124  116  4  5  
165  4.50  165  165  157  149  140  132  124  4  5  
175  5.00  177  175  166  158  149  140  131  4.5  5.5  
185  5.00  184  185  176  167  157  148  139  4.5  6  
195  5.50  196  195  185  176  166  156  146  5  6  
205  5.50  203  205  195  185  174  164  154  5  6.5  
215  6.00  216  215  204  194  183  172  161  5.5  7  
225  6.00  223  225  214  203  191  180  169  6  7  
235  6.50  235  235  223  212  200  188  176  6  7.5  
245  7.00  248  245  233  221  208  196  184  6.5  7.5  
255  7.00  255  255  242  230  217  204  191  6.5  8  
265  7.50  2.67  265  252  239  225  212  199  7  8.5  
275  7.50  274  275  261  248  234  220  206  7  8.5  
285  8.00  286  285  271  257  242  228  214  7.5  9  
295  8.00  294  295  280  266  251  236  221  7.5  9.5  
305  8.50  306  305  290  275  259  244  229  8  9.5  
315  8.50  313  315  299  284  268  252  236  8  10  
325  9.00  325  325  309  293  276  260  244  8.5  10  
335  9.00  333  335  318  302  285  268  251  8.5  10.5  
345  9.50  345  345  328  311  293  276  259  9  11  
355  10.00  357  355  337  320  302  284  266  9  11  
365  10.00  364  365  347  329  310  292  274  9.5  11.5  
a  The figures are based on normal tread pattern tyres.  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
16                                                                                            © EAC 2004 — All rights reserved  
Table A.2 — Dimensional guidelines for metric “70”, “65” and “60” series tyres on 5° tapered 
rims  
 
Nominal 
section 
width  Theoreti
c. rim 
width  Measuring 
rim width 
code  Design 
section 
width  Design section height a 
, H  Approved rim width codes  
mm  min.  max.  SN  
 Rth  
 Rm  
 
 S  
Nominal aspect ratios, 
H/S 70 65 60  Nominal aspect ratios, 
H/S  Nominal aspect 
ratios, H/S  
mm K1 
=0.70  K4 =0.75  mm 70 65 60 70 65 60 70 and 65 60 
165  4,55  5,0  170  116  107  99  4.5  4.5  4.5  5  5.5 
175  4,82  5,0  177  123  114  105  4.5  5  5  5.5  5.5 
185  5,10  5,5  189  130  120  111  5  5  5.5  6  6 
195  5,37  6,0  201  137  127  117  5  5.5  5.5  6  6.5 
205  5,65  6,0  209  144  133  123  5.5  5.5  6  6.5  6.5 
215  5,93  6,5  221  151  140  129  5.5  6  6  7  7 
225  6,20  6,5  228  158  146  135  6  6  6.5  7  7.5 
235  6,48  7,0  240  165  153  141  6  6.5  6.5  7.5  7.5 
245  6,75  7,0  248  172  159  147  6.5  7  7  7.5  8 
255  7,03  7,5  260  179  166  153  7  7  7.5  8  8.5 
265  7,30  8,0  272  186  172  159  7  7.5  7.5  8.5  8.5 
275  7,58  8,0  279  193  179  165  7.5  7.5  8  8.5  9 
285  7,85  8,5  292  200  185  171  7.5  8  8  9  9.5 
295  8,13  8,5  299  207  192  177  8  8  8.5  9.5  9.5 
305  8,41  9,0  311  214  198  183  8  8.5  8.5  9.5  10 
315  8,68  9,5  323  221  205  189  8.5  8.5  9  10  10 
325  8,96  9,5  331  228  211  195  8.5  9  9.5  10  10.5 
335  9,23  10,0  343  235  218  201  9  9  9.5  10.5  11 
345  9,51  10,0  350  242  224  207  9  9.5  10  11  11 
355  9,78  10,5  362  249  231  213  9.5  10  10  11  11.5 
365  10,06  11,0  375  256  237  219  9.5  10  10.5  11.5  12 
a
  The figures are based on normal tread pattern tyres.  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            17   
Table A.3 — Dimensional guidelines for metric series “55” and “50” series tyres on 5° tapered 
rims  
 
Design section height a, 
H  
mm  Nominal 
section 
width  
 
SN  Theoretical 
rim width  
 
 
Rth  Measuring 
rim width 
code  
 
Rm  Design 
section 
width  
 
S  Nominal aspect ratios, 
H/S Approved rim width 
codes min. max.  
  
 
mm K1 = 0.70  K4 =0,80  mm 55 50 Min. Max. 
165  4,55  5,0  170  91  83  5  5.5  
175  4,82  5,5  182  96  88  5  5.5  
185  5,10  6,0  194  102  93  5.5  6  
195  5,37  6,0  201  107  98  6  6.5  
205  5,65  6,5  214  113  103  6  6.5  
215  5,93  7,0  226  118  108  6.5  7  
225  6,20  7,0  233  124  113  6.5  7.5  
235  6,48  7,5  245  129  118  7  7.5  
245  6,75  7,5  253  135  123  7  8  
255  7,03  8,0  265  140  128  7.5  8.5  
265  7,30  8,5  277  146  133  8  8.5  
275  7,58  8,5  284  151  138  8  9  
285  7,85  9,0  297  157  143  8.5  9.5  
295  8,13  9,5  309  162  148  8.5  9.5  
305  8,41  9,5  316  168  153  9  10  
315  8,68  10,0  328  173  158  9.5  10  
325  8,96  10,0  336  179  163  9.5  10.5  
335  9,23  10,5  348  184  168  10  11  
345  9,51  11,0  360  190  173  10  11  
355  9,78  11,0  367  195  178  10.5  11.5  
365  10,06  11,5  380  201  183  11  12  
a  The figures are based on normal tread pattern tyres.  
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
18                                                                                            © EAC 2004 — All rights reserved  
Annex B 
(informative) 
 
Guideline values for metric series, 15° rims 
 
B.1 The values given in table B.1 are for information. 
 
B.2 These values will serve as a guideline for design of tyre dimensions, metric series, mounted on 
15° rims tapered drop-centre rims (code-designated).  For tyres mounted on 15° tapered drop-centre 
rims (code-designated), see Annex A.  For tyres mounted on different types of rims (millimetre-
designated) other annexes will be established. 
 
Table B.1 —  Guideline values for metric series, 15° rims  
 
Nominal 
section 
width a b  Measuring 
rim width 
code  Design 
section 
width  Design section height c, H mm  Approved rim width codes d  
 
SN  Rm  S  Nominal aspect ratios, H/S  Nominal 
aspect ratios, 
H/S 90 to 70  Nominal 
aspect ratio, 
H/S 65  
mm   mm  90  85  80  75  70  65  min.  max.  min.  max. 
175  5.25  176  158  149  140  131  123  114  5.25  5.25  5.25  6.00 
185  5.25  183  167  157  148  139  130  120  5.25  6.00  5.25  6.00 
195  6.00  197  176  166  156  146  137  127  5.25  6.00  6.00  6.00 
205  6.00  204  185  174  164  154  144  133  6.00  6.75  6.00  6.75 
215  6.00  211  194  183  172  161  151  140  6.00  6.75  6.00  6.75 
225  6.75  226  203  191  180  169  158  146  6.00  6.75  6.75  7.50 
235  6.75  233  212  200  188  176  165  153  6.75  7.50  6.75  7.50 
245  7.50  248  221  208  196  184  172  159  6.75  7.50  7.50  8.25 
255  7.50  255  230  217  204  191  179  166  6.75  8.25  7.50  8.25 
265  7.50  262  239  225  212  199  186  172  7.50  8.25  7.50  8.25 
275  8.25  276  248  234  220  206  193  179  7.50  9.00  8.25  9.00 
285  8.25  283  257  242  228  214  200  185  7.50  9.00  8.25  9.00 
295  9.00  298  266  251  236  221  207  192  8.25  9.00  9.00  9.75 
305  9.00  305  275  259  244  229  214  198  8.25  9.75  9.00  9.75 
315  9.00  312  284  268  252  236  221  205  9.00  9.75  9.00  10.50 
325  9.75  327  293  276  260  244  228  211  9.00  10.50  9.75  10.50 
335  9.75  334  302  285  268  251  235  218  9.00  10.50  9.75  10.50 
345  10.50  348  311  293  276  259  242  224  9.75  10.50  10.50  11.75 
355  10.50  355  320  302  284  266  249  231  9.75  11.75  10.50  11.75 
365  10.50  362  329  310  292  274  256  237  9.75  11.75  10.50  11.75 
375  10.50  369  338  319  300  281  263  244  10.50  11.75  10.50  12.25 
385  11.75  389  347  327  308  289  270  250  10.50  12.25  11.75  12.25 
395  11.75  396  356  336  316  296  277  257  10.50  12.25  11.75  13.00 
405  11.75  403  365  344  324  304  284  263  11.75  13.00  11.75  13.00 
415  12.25  415  374  353  332  311  291  270  11.75  13.00  12.25  13.00 
425  12.25  422  383  361  340  319  298  276  11.75  13.00  12.25  14.00 
435  13.00  437  392  370  348  326  305  283  11.75  14.00  13.00  14.00 
445  13.00  444  401  378  356  334  312  289  12.25  14.00  13.00  14.00 
455  13.00  451  410  387  364  341  319  296  12.25  14.00  13.00  15.00 
Footnotes a to d: see next page.  DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            19   
 
 a For a given series, follow either "option 1" or "option 2" as a guideline for the nominal tyre section, SN:  
 Option 1  Option 2  
 ... ... 
 175 175 
 185 185 
 195 195 
 205 205 
 215 215 
 225 225 
 235 235 
 255 245 
 275 265 
 295 285 
 315 305 
 Continue Continue 
 with either "option a" with either "option b" 
 or "option b" or "option c" 
 
  
Option a  Option b  Option c  
 345 335 325 
 375 365 355 
 405 395 385 
 435 425 415 
 ... 455 445 
 ... ... ... 
b  These lists are open-ended. For other nominal tyre section widths, SN, lower than 175 or higher than 445, other 
annexes will be established as necessary.  
c  The figures are based on normal tread pattern tyres.  
d  Other rims may be specified in relation to special services by agreement among tyre, rim, wheel and motor vehicle 
manufacturers  
 
 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
20                                                                                            © EAC 2004 — All rights reserved  
Annex C 
(informative) 
 
Tyre dimension tables 
 
C.1 The dimensions given in this annex are for information.  
 
C.2 Example of dimension table of a tyre having nominal section width 185, nominal aspect ration 
90, radial, nominal rim diameter code 16, mounted on 5° tapered rim: 
 
 
Design tyre Maximum tyre dimensions  
in - service   
Tyre size 
designation   
Measuring rim 
width code  
Section width 
S 
 
mm  
Overall  diameter 
D
o 
 
mm  
Overall width 
W max. 
 
mm  
Overall diameter 
D o max. 
 
mm 
 
185/90 R 16  
500  
184  
740  
193  
753 
 
 
 
C.3   Example of dimension table of a tyre having nominal section width 265, nominal aspect ratio 
75, diagonal, nominal rim diameter code 19.5 mounted on 15° tapered rim (drip-centre): 
 
 
 
Design tyre 
 Maximum tyre dimensions  
in - service  
 
Tyre size 
designation   
Measuring 
rim width 
code  
Section width 
S 
 
mm  
Overall diameter 
D
o 
 
mm  
Overall width 
W max 
 
mm  
Overall diameter 
D o max 
 
mm 
 
265/ 75 D 19.5   
7.50  
262  
893  
280  
925 
 
 
C.4 Example of dimension table of a tyre having nominal section width 305, nominal aspect ratio 
45, construction Z, nominal rim diameter 500,  mounted on a new concept rim with rim/section ratio 
0,5: 
 
Design tyre Maximum tyre dimensions  
in - service  
 
Tyre size 
designation   
Measuring 
rim width  
 
 
 
mm  
Section width 
S 
 
 
mm  
Overall diameter 
D
o 
  
mm  
Overall width 
W 
max 
  
mm  
Overall diameter 
D 
o max 
  
mm 
 
 
305 / 45 Z 500   
150  
304  
814  
314  
824 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            21   
Annex D 
(informative) 
 
Test conditions for tyres with non-standard marking 
 
For an interim period, it is permissible for tyres not to be marked with a load index, but with a “load range” or equivalent ply rating “PR” marking.  Table D1 and D2 apply in place of Tables 7 and 8 
respectively.  
 
Table D.1  – Plunger diameter 
 
 
 
Tyre type   
Plunger diameter 
± 0.5 
 
 
Tyre marked “LT” Tyres with rim diameter code ≤ 12 
Tyres with rim diameter code ≤ 17.5 and marked “TUBELESS” 
   
19 
 
Other than above: 
—  Tyres marked LOAD RANGE F (or 12PR) and below 
—  Tyres marked LOAD RANGE F (or 12PR) and over 
   
32 
38 
 
 
Table D.2  – Endurance test 
 
 
Percentage of maximum load rating 
  
Marking 
of speed 
restricted 
service  
 
Load range   
PR  
Test drum 
speed 
r/min  
7 h 
(Period 1) Duration    
16h 
(Period 2)  
24 h 
(Period 3) 
 
50 mile/h  
all  
all  
125  
66  
84  
101 
 
 
50 mile/h C,D 
E to L 6; 8 
10 to 20 150 
100 75 66 97 84 114 101 
 
 
35 mile/h  
all  
all  
75  
66  
84  
101 
 
 
 
(no 
markings)  
A to D 
E 
F 
G 
H to N  
2 to 8 
10 
12 
14 
16 to 24  
250 200 
200 
175 150  
75 
1) 
70 
66 
66 66 
  
97 
2) 
88 
84 
84 84 
  
114 106 
101 
101 101 
 
1) 4 h for tyres with rim diameter code 14.5 or less. 
2)  6 h for tyres with rim diameter code 14.5 or less.  
  DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
22                                                                                            © EAC 2004 — All rights reserved  
 
 
 
 
 
 
Figure 1 — Typical section: crossply (diagrammatic only) 
 
 
 
Figure 2 — Typical section: radial (diagrammatic only) 
 
  
 
 
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            23  
 
 
Figure 3 — Typical section: crossply (diagrammatic only) 
 
  
 
 
Figure 4 — Typical section: radial (diagrammatic only) 
 
 
  
 
  DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
24                                                                                            © EAC 2004 — All rights reserved 
 
 
 
Figure 5 — Typical section: pneumatic tyre bead 
  
  
 
  
 
   
 
  
 
 
 
   
 DRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
© EAC 2004 — All rights reserved                                                                                            25  
 
Figure 6 — Venting  
 
 
 
  
   
 
  DRAFT UGANDA STANDARD ON PUBLIC REVIEWDRAFT UGANDA STANDARD ON PUBLIC REVIEWEAS 357:2004  
 
 
© EAC 2004 — All rights reserved