FOR COMMENTS ONLY FINAL DRAFT UGANDA 
STANDARD  
  FDUS EAS 31 
Second  Edition  
2013-mm-dd 
 
 Reference number  
FDUS EAS 31: 2013 
© UNBS 201 3 
  
Laundry soap — Specification  
 FOR COMMENTS ONLYFDUS EAS 31: 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. 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 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  
 FOR COMMENTS ONLYFDUS EAS 31: 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 Uganda. 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 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 Final Draft Uganda Standard, FDUS EAS 31: 2013 , Laundry soap — Specification , is identical with  and 
has been reproduce d from an East African  Standard, EAS 31: 20 13, Laundry soap  — Specification , and is 
being proposed for adoption as a Uganda Standard.  
This standard was developed by the Chemicals and environment Standards Technical Committee (UNBS/TC 5).
 
This standard cancels and replaces US EAS 31:2011 Laundry soap — Specification, which has been technically
revised.
 
Wherever the words, “ East African Standard" appear, they should be replaced by "Uganda Standard." 
 FOR COMMENTS ONLY EAS 31: 2013 
ICS 77.100.40 
© EAC 2013                                                                                                                         Third Edition 2013  
 
EAST AFRICAN STANDARD 
Laundry soap — Specification 
EAST AFRICAN COMMUNITY FOR COMMENTS ONLYFOR COMMENTS ONLYEAS 31: 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 process 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  
P.O.Box 1096 
Arusha 
Tanzania 
Tel: 255 27 2504253/8 
Fax: 255 27 2504481/2504255 
E-mail: eac@eachq.org 
       Web: www.eac-quality.net 
Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. 
Violators may be persecuted FOR COMMENTS ONLYEAS 31: 2013 
© EAC 2013  – All rights reserved  iii 
 Contents Page 
Foreword ............................................................................................................................................................  iv 
1 Scope  ................................ ................................ ................................ ................................ ...................... 1 
2 Normative references  ................................ ................................ ............................................................  1 
3 Terms and definitions  ................................ ................................ ...........................................................  1 
4 Grades of laundry soap  ................................ ................................ ................................ ........................ 3 
5 Requirements  ................................................................ ................................ ................................ ......... 3 
5.1 General requirements  ................................ ................................ ...........................................................  3 
5.1.1  Appearance  ................................................................ ................................ ................................ ............ 3 
5.1.2  Texture  ................................ ................................ ................................ ................................ .................... 3 
5.1.3  Odour  ................................ ................................ ................................ ................................ ...................... 3 
5.1.4  Colouring matter  ................................ ................................................................ ................................ .... 3 
5.1.5  Stability  ................................ ................................ ................................ ................................ ................... 3 
5.1.6  Toxicity  ................................ ................................ ................................ ................................ ................... 3 
5.2 Specific quality requirements  ................................ ................................ ................................ .............. 3 
6 Sampling  ................................ ................................ ................................ ................................ ................ 4 
8 Packaging and marking  ................................ ................................ ................................ ........................ 5 
8.1 Packaging  ................................ ................................ ................................ ................................ ............... 5 
8.2 Marking  ................................ ................................ ................................ ................................ ................... 5 
8.2.1  Packaging  ................................ ................................ ................................ ................................ ............... 5 
8.2.2 Wrapper  ................................ ................................ ................................ ................................ .................. 5 
8.2.3  Bars or cakes  ................................................................ ................................ ................................ ......... 5 
9 Criteria for conformity ................................ ................................ ...........................................................  5 
Annex A (normative)  Determination of staining test of laundry bar soap ................................................... 6  
A.1 Method 1: Undissolved powder (5.0 % product concentration)  ................................ ....................... 6 
A.1.1  Principle  ................................ ................................ ................................ ................................ ................. 6 
A.1.2  Materials  ................................ ................................ ................................ ................................ ................. 6 
A.1.3  Procedure  ................................ ................................ ................................ ................................ ............... 6 
A.2 Method 2: Pre -dissolved soap (2.5 % product concentration)  ................................ ......................... 6 
A.2.1  Principle  ................................ ................................ ................................ ................................ ................. 6 
A.2.2  Materials  ................................ ................................ ................................ ................................ ................. 6 
A.2.3  Procedure  ................................ ................................ ................................ ................................ ............... 6 
Annex B (normative)  Sampling ........................................................................................................................ 7  
B.1 Procedure  ................................ ................................ ................................ ................................ ............... 7 
B.2 Preparation of test samples  ................................ ................................ ................................ ................. 7 
B.2.1  Composite sample  ................................ ................................................................ ................................ . 7 
B.2.2  Samples for testing  ................................ ................................ ...............................................................  7 
 FOR COMMENTS ONLYEAS 31: 2013 
iv © EAC  2013  – 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 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 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 .  
EAS 31  was prepared by Technical Committee EASC/TC 074, Surface active agents . 
This third edition cancels and replaces the second edition (EAS 31 :2011), which has been technically revised. 
 
 FOR COMMENTS ONLYEAST AFRICAN STANDARD  EAS 31: 2013  
 
© EAC 2013  – All rights reserved  1 
 Laundry soap — Specification 
1 Scope 
This East African Standard specifies requirements, sampling and test methods for two grades of laundry 
soaps. This standard covers two grades of laundry soap pure and built laundry soap in the form of cakes, 
tablets or bars, produced from vegetable or animal oils or fats or a blend of all or part to these materials.  
It does not cover liquid soap for household purposes, and bar soap, in which synthetic detergents have been 
added to enhance its performance. 
2 Normative references 
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies. 
ISO 456, Surface-active agents — Determination of free caustic alkali 
ISO 457, Analysis of soap — Determination of chloride content  
ISO 672, Analysis of soap — Determination of moisture and volatile matter content  
ISO 673, Analysis of soap — Determination of ethanol insoluble matter  
ISO 684, Analysis of soap — Determination of total free alkali  
ISO 685, Analysis of soap — Determination of total alkali content and total fatty matter content  
ISO 862, Surface active agents — Vocabulary  
ISO 1067, Analysis of soap — Determination of unsaponifiable, unsaponified, and unsaponified saponifiable 
matter  
ISO 6839, Anionic surface active agents — Determination of solubility in water  
3 Terms and definitions 
For the purposes of this standard, the terms and definitions given in ISO 862 and the following apply.  
3.1  
batch  
soap from one vat or pan. In the continuous production process, the soap from one day’s production shall 
constitute a batch. 
3.2 
builder 
complementary component of soap, usually inorganic, which with reference to the washing action, adds its 
characteristic properties to those of the essential constituents FOR COMMENTS ONLYEAS 31: 2013 
2 © EAC  2013  – All rights reserved  
 NOTE Builders are added to a soap to improve its effectiveness under the conditions of use. The action of builders is 
mostly physico-chemical and comprises a series of effects, which results in more economic usage and better cleansing 
action of soap especially in hard water areas. Substances commonly used as builders are soda ash, sodium silicates, 
sodium phosphates, borax and cellulose derivatives.  
3.3 
built laundry soap 
grade II laundry soap containing moderate quantities of builders (see Table 1)  
3.4 
colouring matter 
any dyestuff that may be used to colour laundry soap 
3.5 
fillers 
materials added to soaps to increase the mass of the product but which in themselves do not improve 
effectiveness of the soap under the conditions of use 
NOTE Fillers are generally inert and of an almost or completely non-detergent character. 
3.6 
free caustic alkali 
quantity of hydroxyl ion, reported as sodium hydroxide (NaOH) for sodium soaps or potassium hydroxide 
(KOH) for potassium soaps, which is found in solution after precipitation with barium chloride under the 
operating conditions described. 
3.7 
laundry soap 
soap which is intended for use in washing clothes 
NOTE Laundry soap may contain fillers, builders, colouring matter, perfume, optical brighteners, preservatives, 
glycerine or opacifiers. 
3.8 
lot 
identified quantity of laundry soap produced under essentially the same conditions 
3.9 
pure laundry soap 
well saponified soaps which, in addition to moisture, may contain amounts of other substances, such as 
colouring matter, perfume, preservative, opacifiers and optical brightening agents. 
3.10 
total fatty matter 
water-insoluble fatty material obtained by decomposing the soap with a mineral acid under the conditions 
specified. This term includes unsaponified matter, glycerides and any rosin acids contained in the soap, in 
addition to the fatty acids. 
3.11 
total free alkali 
sum of the free caustic alkali and the free carbonate alkali contents . The results are generally expressed as a 
percentage by mass as either sodium hydroxide (NaOH) for sodium soaps or potassium hydroxide (KOH) for 
potassium soaps. They may also be expressed in milliequivalents per gram. 
 
3.12  
saponification  
chemical reaction in which a fat is converted into a soap by the action of alkaline  FOR COMMENTS ONLYEAS 31: 2013 
© EAC 2013  – All rights reserved  3 
 4 Grades of laundry soap 
Laundry soap shall be of the following grades and designations: 
a) pure laundry soap, Grade I (see Table 1); and 
b) built/filled laundry soap, Grade II (see Table 1) 
5 Requirements 
5.1 General requirements 
5.1.1  Appearance 
Laundry soap shall be free from visible dirt and other foreign matter. 
5.1.2  Texture  
Laundry soap shall be of firm texture and possess good lathering and cleaning properties. 
5.1.3  Odour 
Laundry soap shall be free from objectionable odour. It shall not leave objectionable odour on clothes after 
washing and thoroughly rinsing with water. 
5.1.4  Colouring matter 
When coloured laundry soap is used in washing any safe white fabric, it shall not leave any visible stains on 
the fabrics after washing and thorough rinsing with water when tested in accordance with Annex A. 
5.1.5  Stability 
When immersed in distilled water for one hour at 25 C – 30 C, laundry soap shall not disintegrate, and when 
dried at room temperature for 25 h thereafter, it shall not crumble, crack or break. 
5.1.6  Toxicity 
The product shall not be injurious to health, because irritation to the skin during use or handling, damage the 
fabrics and shall be environmentally friendly/safe. 
5.2 Specific quality requirements 
Laundry soap shall comply with the specific quality requirements in Table 1. FOR COMMENTS ONLYEAS 31: 2013 
4 © EAC  2013  – All rights reserved  
 Table 1 — Specific quality requirements for laundry soap 
S/No.  Characteristic  Requirement,  
% (m/m)  Methods of 
test 
 
Pure  laundry 
soap  
Grade I  Built/filled laundry 
soap  
Grade II   
i)  Total fatty matter, %, min  62 50 ISO 685  
ii)  Matter insoluble in water, % max.  0.5 5 ISO 6839  
iii)  Matter insoluble in ethanol, % by mass, max  2.5 20 ISO 673  
iv)  Free caustic alkali, as NaOH, % by mass, max 0.2 0.4 ISO 456  
v)  Total free alkali, as NaOH, % by mass, max  0.2 0.3 ISO 684  
vi)  Total free fat (unsaponified and unsaponifiable fatty 
matter), % by mass, max  0.2 2 ISO 1067  
vii)  Sodium Oxide (Na 2O), % max.  0.25 0.4 ISO 456  
viii)  Moisture and volatile matter co ntent at 105 C, % by 
mass, max  30 30 ISO 672  
ix)  Chloride content, as NaCl, % by mass, max  1.5 1.5 ISO 457  
x)  Staining  Shall pass the test  Annex A  
NOTE  1 As laundry soap is liable to lose moisture on keeping, the results of analysis in respect to free caust ic alkali,  
unsaponified fatty matter,  unsaponifiable matter and matter insoluble in alcohol sh ould be recalculated on the basis of the 
minimum specified total fatty matter by means of the equation  
matterf attytotal Actualmatterf attytotal specif ied Minimum results Actual
resultsed Recalculat

 
NOTE 2  As weight of laundry soap is  liable to diminish owing to loss of moisture in the soap, the weight of the soap 
bars or cakes should be recalculated on the basis of the minimum specified total fatty matter.  
EXAMPLE  
If a soap bar during analysis is found to weigh 496 g, the actual total  fatty matter of that bar is found to be 70.0 %, the 
value of unsaponified matter is found to be 0.56 % and the minimum content of total fatty matter is specified as 62.0 %, 
then recalculated value for unsaponified matter is:  
% 0.469
70.062.0 0.56

 
and th e recalculated weight of the soap bar drying is:  
g560
62.070.0 496

 
 
6 Sampling 
Sampling shall be done in accordance to Annex B. FOR COMMENTS ONLYEAS 31: 2013 
© EAC 2013  – All rights reserved  5 
 8 Pack aging and marking 
8.1 Pack aging 
Laundry soap shall be packed in clean, sound and dry containers made of a material, which does not affect 
the product and which protects the product from excessive loss of moisture and shall be from contamination. 
8.2 Marking 
8.2.1 Packaging 
Each package shall be marked legibly and indelibly with the following particulars: 
a) the words “Grade I Laundry Soap ” or “Grade II Laundry Soap ”; 
b) manufacturer’s name and physical address  
 NOTE The name, physical address of the distributor/supplier and trade mark may be added as required 
c) nominal weight of each bar or cake at the time of packaging; 
d) number of bars or cakes contained in the package; 
e) country of origin; 
f) batch number ; and  
g) lot in code or otherwise. 
8.2.2 Wrapper  
On the paper or wrapper in which the bar or cake is wrapped shall be marked with the particulars contained in 
8.2.1 (a) to (b ). 
8.2.3 Bars or cakes  
In case of bars or cakes which, are not wrapped in individual wrapper, the bars or cakes shall be marked with 
brand names or trademarks and where possible. 
9 Criteria for conformity  
The lot shall be deemed to comply with this standard, if after inspection and testing, it complies with the 
requirements specified in Clause 4 and Clause 5. FOR COMMENTS ONLYEAS 31: 2013 
6 © EAC  2013  – All rights reserved  
 Annex A 
(normative) 
 
Determination of staining test of laundry bar soap 
A.1 Method 1: Undissolved powder (5.0 % product concentration)  
A.1.1 Principle 
Test pieces of cloth of defined area are rubbed with soap and then dipped in water overnight then scrubbed 
and rinsed in running water.  
A.1.2 Materials  
Pieces of white cotton, nylon and Crimplene C cloth 
A.1.3 Procedure  
A.1.3.1  Rub evenly about 10 g of soap over a 15 cm x 7.5 cm test swatch placed on a china plate.  
A.1.3.2 Pour gently 50-mL of hot water (approximately 55 °C) into the plate so that the test swatch is 
covered and left overnight (16 h). 
A.1.3.3  Hand rub the swatch 10 times and then rinse each of the three test swatches are rinsed twice in 
about two litres of water and then dried in the drier.  
NOTE The staining test is conducted in triplicate for all cloth types. 
A.2 Method 2: Pre-dissolved soap (2.5 % product concentration)  
A.2.1 Principle 
The method involves subjecting fabrics to prolonged soaking in a highly concentrated soap solution.  
A.2.2 Materials 
Pieces of white cotton, nylon and Crimplene C cloth of dimension 15 cm x 7.5 cm  
A.2.3 Procedure  
A.2.3.1  Weight 10 g of soap in a honey jar and then add 200 mL of hot water at a temperature of 
approximately 60 °C, shake until when the soap is thoroughly dissolved.  
A.2.3.2  Place a test swatch A 15 cm x 7.5 cm in the soap solution (A.2.3.1) and allow to stand overnight.  
A.2.3.3  Transfer the test swatch in a bowl containing one litre of water and then agitate vigorously by 
hand for 10 s.  
A.2.3.4  Rinse the test swatches in 5 L of water by hand. The times should be fixed for all washes, and 
then dry swatches.   
NOTE The staining test should be conducted in triplicate for all cloth types. FOR COMMENTS ONLYEAS 31: 2013 
© EAC 2013  – All rights reserved  7 
 Annex B 
(normative) 
 
Sampling  
B.1 Procedure  
B.1.1 In a single consignment, all packages (cartons) containing toilet soap cakes drawn from the same 
batch of production shall constitute a lot. For ascertaining the conformity of the lot to the requirements of this 
standard, tests shall be carried out on each lot separately. The number of packages to be selected for drawing 
the sample shall be in accordance with Table B.1 .  
Table B.1 — Scale of sampling 
Number of packa ges (cartons) in 
the lot  
N Number of packages (cartons) to be 
selected  
n Number  of samples  
4 to 15  3 3 
16 to 40  4 4 
41 to 65  5 2 
66 to 110  7 2 
111 and above  10 1 
 
B.1.2 The packages shall be selected at random, using tables of random numbers. If these are not 
available, the following procedure shall be applied:  
Starting from any package, count all the packages in one order as 1, 2, 3.... N, selecting every k th package, 
where k is the integral part of N  n.  
B.1.3 From each package thus selected, draw at random an equal number of cakes so as to obtain a total 
mass of at least 2 kg.  
B.2 Preparation of test samples 
B.2.1 Composite sample  
Weigh each cake separately (including any material that may have adhered to the wrapper), and calculate the 
average mass. Cut each of the remaining cakes into eight parts by means of three cuts at right angles to each 
other through the middle. Grate finely the whole of two diagonally opposite eighths of each specimen. Mix the 
gratings and place in a clean, dry, airtight glass container.  
B.2.2 Samples for testing 
Immediately after preparation of composite sample (B.2.1), take at one time all test samples required for the 
tests in 4.2. Weigh out the test sample required for determination of free alkali or acid content, and use it 
immediately.  
 FOR COMMENTS ONLYFOR COMMENTS ONLYEAS 31: 2013    
 
© EAC 2013 – All rights reserved