FINAL DRAFT UGANDA 
STANDARD  
  FDUS EAS 783 
First  Edition  
2013-mm-dd 
 
 Reference number  
FDUS EAS 783: 2013 
© UNBS 201 3 
  
Stainless steel tanks  — Specification  
 FDUS EAS 783: 2013 
ii                © UNBS  2013 - 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. User s are 
responsible for its correct application  
© UNBS 20 13 
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  
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Uganda  
Tel: 256 41 505 995  
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E-mail: unbs@infocom.co.ug  
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 FDUS EAS 783: 2013 
© UNBS  2013 - All rights reserved                 iii National 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 Ugan da. 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/SPS Agreements 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 repres entatives 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 Final Draft Uganda Standard, FDUS EAS 783: 2013, Stainless steel tanks  — Specification , is identical 
with and has been reproduced from an East African  Standard , EAS 783: 2013 , Stainless steel tanks  — 
Specification , and is being proposed for adoption as a Uganda Standard.  
Wherever the words, “ East African  Standard" appear, they should be replaced by "Uganda Standard."  
 
   FDEAS 783: 2013  
ICS 77.140  
© EA C 2013                                                                                                                               First Edition 2013   
 
FINAL DRAFT EAST AFRICAN STANDARD  
Stainless steel tank s ― Specification  
EAST AFRICAN COMMUNITY  FDEAS 783: 2013  
ii © EAC  2013  – All rights reserved  
 Copyright notice  
This EAC document is copyright -protected by EAC. While the reproduction of this document by 
participants in the EAC standards development proce ss is permitted without prior permission from EAC, 
neither this document nor any extract from it may be reproduced, stored or transmitted in any form for 
any other purpose without prior written permission from EAC.  
Requests for permission to reproduce this  document for the purpose of selling it should be addressed 
as shown below or to EAC’s member body in the country of the requester:  
© East African Community  2013  — All rights reserved  
East African Community   
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Tanzania  
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Reproduction for sales purposes may be subject to royalty payments or a licensing agreement.  
Violators may be persecuted  
 
 FDEAS 783: 2013  
© EAC 2013  – All rights reserved  iii 
 Foreword  
Development of the East African Standar ds has been necessitated by the need for harmonizing requirements 
governing quality 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.  
In order to achieve this objective, the Community established an East African Standards Committee mandated 
to develop and issue East African Standards.   
The Committee is composed of representatives of t he 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 Sta ndards are therefore expected to ensure that they always have the latest versions of the standards 
they are implementing .  
FDEAS 783 was prepared by Technical Committee EASC/TC 035, Steel and steel products . FDEAS 783: 2013  
iv © EAC  2013  – All rights reserved  
 Introduction  
Stainless steel tanks are fast bec oming popular in several areas in East Africa especially in urban areas 
where the issue of clean water is critical. East Africa has experienced introduction of this type of tanks in the 
market. These tanks are manufactured locally and some are imported fro m different countries. They are being 
available at different qualities, sizes and, capabilities.  
This standard has been developed  to address the quality issu es and performance of the tanks . 
 
 FINAL DRAFT EAST AFRICAN STANDARD  FDEAS 783: 2013  
 
© EAC 2013  – All rights reserved  1 
 Stainless steel tank s ― Specification  
1 Scope  
This Final Draft East African Standard specifies material, dimensional, and constructional requirements for 
stainless  steel tanks.  
2 Normative references  
The following referenced documents are indispensable for the application of th is document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies.  
ASTM A 751,  Standard test methods, practices, and terminology for chemical analysis  of steel products   
ASTM A 240/A 240M -07, Standard speciﬁcation for chromium and chromium -nickel stainless steel plate, 
sheet, and strip for pressure vesse ls and for general applications   
ISO 6892 -1, Metallic materials — Tensile strength test  
3 Terms and definitions  
For the purposes of this standa rd, the following terms and definitions shall apply . 
3.1  
acceptable  
acceptable to the authority administering this standard, or to the parties concluding the purchase  contract, as 
relevant  
3.2 
bright polished finish  
shining  reflective finish obtained by polishing the surface without complete obliteration of previously existing  
grinding marks or other surface texture  
3.3  
defective  
tank that fails in one or more aspects to comply with the appropriate requirements of  this standard  
3.4 
directional satin fini sh 
finish obtained by so grinding the surface with fine abrasives (without subsequent polishing) as to leave a silky  
appearance, with the abrasive marks running in the same general direction  FDEAS 783: 2013  
2 © EAC  2013  – All rights reserved  
 4 Constructional requirements  
4.1 General requirements  
4.1.1  Material  
The stainless steel used under the speci fied chloride level of the food stuff, shall be AISI/ASTM type 304L, 
type 316L, type 304, or type 316, as specified by the purchaser, and of the relevant composition given in 
Table 1. AISI/ASTM 304 an d 316 are more preferable for  food and surgical use.   
Table 1 — Typical chemical composition of stainless steel  
AISI/ASTM Type  
number* Chemical composition , 
% 
Chromium  Nickel  Carbon, max. Molybdenum  
304 17 – 20 8.0 – 10.5. 0.08 - 
316 16 – 18 10 – 14 0.08 2 – 3 
304L  10 – 20 8 – 12 0.03 - 
316L  16 –- 18 10 – 14 0.03 2 – 3 
*Type 304 is an austenitic stainless steel (commonly known as 18/8) having superior resistance to corrosion and to staining.  Type 
316 is an austenitic stainless steel suitable for severe condi tions such as those in photographic laboratories. These two grades are 
suitable for chlorine less than 200 ppm. When it is necessary to handle hot water or when conservative guideline is necessary , type 
304L and type 316L are more suitable. The type number s are those given by the American Iron and Steel Institute.  
NOTE  Type 316L is more suitable when the chlorine level of the food stuff range between 200 ppm - 250 ppm  
 
4.1.2  Construction  
Tanks shall be made by stamping, pressing, or fabricating, or by a c ombination of  two or more of these 
methods.  
4.1.3 Joints  
All joints shall fit closely, and the whole length of each joint shall be welded. The welded joints shall be ground 
flush with the working face. No solder shall be used on joints.  
4.1.4  Welds  
Welds  shall be fusion welds done by the seaming process or by any other welding process that produces a 
weld having mechanical properties and corrosion resistance of at least the same order as those of the parent 
metal. When tested in accordance with ISO 6892 -1, the strength of the welded point, shall be similar to the 
strength of p arent material, as shown in Table 2 . FDEAS 783: 2013  
© EAC 2013  – All rights reserved  3 
 Table 2  — Mechanical properties  
AISI Type number*  Tensile strength,  
MPa Yield strength,  
MPa Elongation,  
% in 50 mm  Rockwell hardness  
304 560 210 55 B76 
316 595 245 55 B80 
304L  560 210 55 B76 
316L  595 245 55 B80 
 
4.1.5  Finish  
All exposed surfaces shall be free from buckles, dents, pits, deep scratches, and other defects, and shall have 
a medium directional satin or a bright polished finish, as  specified by the purchaser. The tanks shall be free 
from dirt, grease, graphite, and other foreign matter.  
4.2 Specific requirements  
4.2.1  Design and dimensions  
The design of the tank shall either be square, round, rectangle or cylindrical or as may be  agreed between the 
purchaser and the manufacturer. The dimensions shall be in accordance with the  purchaser and manufacturer 
agreement with respect to design requirements. The minimum thickness of the material used for 
manufacturing the tank shall be 0.3 mm . Normal tolerances of 0.0254 mm shall apply to the thickness of the 
material . 
4.2.2  Construction  
The tank shall be grooved around the circumference with minimum number of five grooves. The tank shall  
consist of two holes at the top, one for the inlet and other for tank breathing , and two holes at the  bottom , one 
for the outlet  and the other for draining during cleaning.  
4.2.3  Leakage  
The tank shall not show any leakage when tested in accordance with 7 .3. 
4.2.4 Hydrostatic pressure  
The tank shall withstan d hydrostatic force when tested in accordance with 7 .4. 
5 Marking   
Each tank shall be legibly and indelibly marked with the following information on the surface of the tank:  
a) manufacturer's name  and address ;  
b) capacity of the tank ; 
c) type of steel used,  
d) batch number of the tank; and  
e) thickness of the material . FDEAS 783: 2013  
4 © EAC  2013  – All rights reserved  
 6 Sampling and compliance  
6.1 Sampling  
6.1.1  General  
The sampling procedure s in 6.1.2 and 6.1.3  shall be applied in determining whether a lot complies with the 
appropriate  requirements of th is standard . The samples so taken shall be deemed to represent the lot for the  
respective properties.  
NOTE  This clause  applies to the sampling for inspection and testing before acceptance or rejection of single lots 
(consignments) in cases where no information about the implementation of quality control or testing during manufacture is 
available to help in assessing the quality of the lot. It is also used as the procedure for adjudications in cases of dispute .  
6.1.2 Sample for inspection  
From the lot, random samplin g shall be done in accordance with Table  3. 
Table 3 — Sample for testing and inspection  
Lot size  Sample size  
Sample for inspection  Sample for testing  Defective acceptance 
number  
Less than 20  All 1 0 
20 – 100 20 2 1 
 
6.1.3 Sample for testing  
From each  sample taken in accordance with 6 .1.2, random  sampling of  the number of tanks relative to the 
appropriate lot size  shall be done in accordance with  Table 3 . 
6.2 Compliance  
The lot shall be deemed to comply with the requirements of this standard,  if after inspection and testing  
a) the number of defectives found in the sampl e taken in accordance with 6.1.2 does not exceed  the 
appropriate acceptance number given in Table 3; and  
b) no defective is found in the sample taken in accord ance with 6.1.3. 
7 Inspection and methods of test  
7.1 Inspection  
Inspect ion of sample s shall be done  in accordance with 6.1.2 for compliance with the appr opriate 
requirements of  clauses 4, 5, and 6 other than those given in 4.1 .1. 
7.2 Chemical analysis of stainless steel  
Use the method described in ASTM A 751, or any other approved method, to determine the  chemical 
composition of the steel used in the manufacture of each tank in the sampl e taken in accordance with 6.1.3.  FDEAS 783: 2013  
© EAC 2013  – All rights reserved  5 
 7.3 Leakage test  
Fill water to the full capacity of the tank under  room temperature and atmospheric pres sure and leave it for 15 
min. Observe if there is any leakage.  
7.4 Pressure test  
Fill water to the full capacity of the tank under room temperature and atmospheric pressure and le ave it for 15 
min.  
The tank shall with stand the hydrostatic pressure calcu lated by the following formula:   
P = ρhg 
where: 
P is the hydrostatic pressure;  
ρ is the d ensity of food stuff ; 
h in the h eight of the tank ; and  
g is the a cceleration due to gravity . 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 FDEAS 783: 2013  
6 © EAC  2013  – All rights reserved  
  
Bibliography  
 
SANS 9 06:2006,  Stainless steel wash -hand basins  Published by South Africa  Bureau of Standards  
Henkel and Pense, 2002, Structure and properties of engineering materials , fifth edition, published by Mc 
Graw – Hill, New York  
 
 FDEAS 783: 2013    
 
© EAC 2013  – All rights reserved