DEAS 812 : 2022 
ICS 77.100.40  
© EA C 2022                                                                                                                   Second  Edition 2022 
 
 DRAFT EAST AFRICAN STANDARD  
Synthetic and combined (soap and synthetic) liquid hand wash – 
Specification  
 
EAST AFRICAN COMMUNITY  DEAS 812 : 2022 
ii © EAC  2022 – All rig hts reserved  
 Copyright notice  
This EAC document is copyright -protected by EAC. While the reproducti on of this documen t 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 pr ior written permis sion f rom 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 r equester:  
© East African Community  2022 — All rights reserve d 
East African Com munity  
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.  
Viola tors may be prosecuted . DEAS 812 : 2022 
© EAC 2022 – All rights reserved  iii 
 Contents  Page  
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Requirements  ................................ ................................ ................................ ................................ .........  2 
4.1 General requirements  ................................ ................................ ................................ ...........................  2 
4.2 Specific re quirements  ................................ ................................ ................................ ...........................  2 
5 Packaging  ................................ ................................ ................................ ................................ ...............  3 
6 Labelling  ................................ ................................ ................................ ................................ .................  3 
Annex A (normative) Test for lather volume ................................ ................................ ................................ .... 3 
A.1 General  ................................ ................................ ................................ ................................ ...................  3 
A.2 Outline of the method  ................................ ................................ ................................ ...........................  4 
A.3 Reagents  ................................ ................................ ................................ ................................ ................  4 
A.4 Apparatus  ................................ ................................ ................................ ................................ ...............  4 
A.5 Preparation of standard hard water  ................................ ................................ ................................ ..... 4 
A.6 Procedure  ................................ ................................ ................................ ................................ ...............  4 
A.7 Calculation  ................................ ................................ ................................ ................................ .............  5 
Annex B (normative)  Determination of active det ergent content  ................................ ................................ . 6 
B.1 Outline of the method  ................................ ................................ ................................ ...........................  6 
B.2 Reagents  ................................ ................................ ................................ ................................ ................  6 
B.3 Procedure  ................................ ................................ ................................ ................................ ...............  6 
B.4 Alternative method for determination of active detergent content  ................................ ..................  7 
Annex C (normative)  Sampling  ................................ ................................ ................................ ......................  11 
C.1 Procedure  ................................ ................................ ................................ ................................ .............  11 
C.2 Preparation of test samples  ................................ ................................ ................................ ...............  11 
Bibliography  ................................ ................................ ................................ ................................ ......................  12 
 DEAS 812 : 2022 
iv © EAC  2022 – All rig hts reserved  
 Foreword  
Developm ent of the East A frican S tandards 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 stan dardization,  trade barrie rs that are enco untered when good s and se rvices are exchanged 
within the Community will be removed.  
The Community has established an East Afri can Standards Committee (EASC) mandated to develop and 
issue  East African Standards (EAS ) and other deliverables. The Com mittee i s composed of rep resentat ives of 
the National Standards Bodies in Partner States, tog ether with the representatives from the pu blic and private 
sector organizations in the community.  
East African Standards are deve loped throug h Technical Committee s that a re representative  of key 
stakeholders including government, academia, consumer groups , private sector and other interested part ies. 
Draft East African Standards are circulated to stakehol ders through the National St andards Bodi es in the 
Partner Sta tes. The  comments receive d are di scussed and incorporated before finalization of standards, i n 
accordance with the Principles and proce dures for development of East African Standards.  
East Afric an Standards and other deliv erables are subject to review, to  keep pa ce with technolog ical 
advances. Users of the East African Standards are therefore exp ected to ensure that they always have the 
latest versions of the standards they are implementing.  
The committee responsible for t his document  is Technical Committ ee EASC/ TC 074, Surface a ctive ag ents 
Attention is drawn to the possibility that some of the elements of this document may be subject o f patent 
rights. EAC shall not be held responsible for ident ifying any or all such paten t rights.  
This second  edition can cels and  replaces the first edition (EAS 812-1:2015), which has been technically 
revised.  
 
 DEAS 812 : 2022 
© EAC 2022 – All rights reserved  v 
 Introduction  
Liquid hand wash has become ve ry common nowadays as liquid soaps are ea sy to use , even for  children.  
They come in dif ferent types and most types of liquid hand wash have moisturizers and anti -oxidants in  their 
formulation s, such as Vitamin E or Aloe , that help to protect the skin.  Permitted f ragrances and dyes are 
among some of the oth er ingredients  used in their formulati ons. 
Liquid hand wash on the market are either soap based, combined (soap and synthetic) or pure synthetic with 
most product s being either synthetic or combined (soap  and synthetic).  
Due to the scarcity of fats and oi ls, technology is moving towards the s ynthetic type of hand wash as opposed 
to soap based.  
This necessitated the development of this standard to guide the quality  and safety of synthetic and combined 
(soap and synthetic) products on the market.DEAS 812 : 2022   
 
© EAC 2022 – All rights  reserved  
  
 Synthetic and combined (soap and synthetic) liquid hand wash – 
Specification  
 
1 Scope  
This Draft  East African Standard specifies  the requirement s, sampling  and test methods  for synthetic and 
combined (soap and synthetic) hand wash .  
This standard does not apply to only soap -base d hand wash . 
2 Normative referen ces 
The following referenced documents are indispensable for the application of this docu ment. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (incl uding any amendments) applies.  
ASTM  D1569 , Standard test method for detergent alkylate   
EAS 217 -1-1, Methods for  the microbiological examination of foods — Part 1 -1: General procedures and 
techniques  
EAS 377 -1, Cosmetics and cosmetics products — Part 1: Li st of substances prohibited in c osmetic  products  
EAS 377 -2, Cosmetics and cosmetics products — Part 2: List of s ubstances which cosmetic products must 
not contain except subject to restrictions laid down  
EAS 377 -3, Cosmetics and cosmetics products — Part 3: List of colourants allowed in  cosmet ic products  
EAS 377 -4, Cosmetics and cosmetics products — Part 4: List of  preservatives allowed in cosmetic products  
EAS 377 -5, Cosmetics and cosmetics products — Part 5: Use of UV filters in cosmetic products  
EAS 794 , Determination of the microbial  inhibi tion of cosmetic soap bars and liquid hand and body washes — 
Test method  
ISO 4314,  Surface active agents — Determination of free alkalinity or free acidity — Titrimetric method  
ISO 862 , Surface active agents — Vocabul ary 
ISO 4316 , Surface active age nts — Determination of pH of aqueous solutions — Potentiometric method  
3 Terms a nd definitions  
For the purposes of this standard terms and definitions given in  ISO 862 shall apply.  
ISO and IEC maintain terminological databases for use in standardization at the fo llowing addresses:  
— ISO Online b rowsing platform: available at http://w ww.iso.org/obp   
2 © EAC  2022 – All rig hts reserved  
  
4 Requirements   
4.1 General requirements  
4.1.1 All ingredients  used  in the liquid hand wash  shall comply with the requirements of all parts of EAS 
377. 
4.1.2 If humectants , for example  glycerine or propylene glyc ol, are part of the formulation,  the total amou nt 
should not be less than 1  % m/m.  
4.1.3 The liquid hand wash  shall not have any  objectionable  odour.  
4.1.4 The liquid hand wash  shall not be irritating to the normal skin , and shall not contain ingredients in 
quantities that are toxic to human beings.  
4.1.5 If the liquid hand wash  contain s herbal extracts , the total herbal extracts ( for exam ple neem or Aloe 
Vera ) amount shall not be less than 0.01 % m/m of the 10 0 % (pure) active ingredient . 
4.2 Specific requirements  
The liquid hand wash  shall also co mply with the specific requirements given in Table 1 when tested in  
accordance with the corresponding test meth od. 
Table 1 — Specific requirements f or liquid hand wash  
Sl No  Characteristic  Requirement  Test method  
Synthetic  Combined (synt hetic 
and Soap)  
i) Total active content, min, % m/m , min  5 10 Annex B  
ii) pH at 20°C, neat, range  3.5 a) – 8 3.5 a) – 8 ISO 4316  
iii) Specific gravity at 20°C   0.85 - 1.40 0.85 - 1.40 ASTM  D1569  
iv) Free fatty acid content  (as oleic acid), % 
m/m, max . — 1 ISO 4314  
v) Lather volume, ml, min., 110 110 Annex A  
vi) Total plate  count, cfu/g . max 100 300 
EAS 217 -1-1 
Yeast & Mold, cfu/g  max 100 100 
vii) Antibacterial activity  b) To pass t he test  EAS 794.  
a) Only weak acids should be used suc h as lac tic acid, citric acid , benzoic acid  etc 
b) Only for liquid hand wa sh contain ing antib acterial agents  claims . 
 
  
© EAC 2022 – All rights reserved  3 
 5 Packaging  
5.1 The liquid hand was h shall be pack aged in suitable well -closed containers . 
5.2 The containers/packages (including the closures) shall not impart any  contamination  to the liquid ha nd 
wash  and shall be strong enough to protect the content adequately during normal handling, tran sportation and 
storage . 
5.3 Only containers/packages of the sam e size and bearing the same batch identification shall be pa cked 
together in a bulk containe r/package . 
6 Labelling  
Each container and bulk package  shall be securely closed , legibly and indelibly labelled either in English, 
Kiswahili or French or combination or any  other language as agreed between the manufactu rer and supplier 
with the following inf ormation: 
a) name of the product as “ liquid hand wash ”;  
b) indication of whether the product is synthetic or combine d (soap and synth etic) 
c) manufacturer’s name and physical address;  
NOTE : The name, physical address of the distributor/suppli er and trade mark may  be added as required.  
d) batch or lot number ; 
e) net content;  
f) list of ingred ients used ; 
g) country of or igin; 
h) instructions for use  
i) date of manufacture ; and  
j) best before date .  
k) indicate mode of disposal of containers/ packages   
7  Sampling  
Samp ling shall be done in  accordance with Annex C. 
 
Annex A  
(normat ive) 
Test for lather volume  
A.1 General  
Strict attention shall be paid to all details of the p rocedure in order to ensure concordant results. Particular 
care should be taken to invert the cylin der exa ctly as descri bed.  
4 © EAC  2022 – All rig hts reserved  
 A.2 Outline of the method  
A suspensio n of the material in standard hard water is taken in a graduated cylinder and given 12  inversi ons 
under prescribed conditions. The volume of the foam formed is observed after keeping the cylind er for 5 
minutes.  
A.3 Reagents  
A.3.1  Calcium chloride CaCl 2.2H 2O, AR 
A.3.2  Magnesium sulphate MgSO 4.7H 2O, AR 
A.3.3  Distilled water  
A.4 Apparatus  
A.4.1 Gradua ted cylinder  — Glass stoppered with graduation from 0 t o 250 ml, with 2 ml divisions. Over all 
heigh t about  35 cm and the  height of the graduated portion about 20 cm. 
A.4.2  100-ml glass beaker  
A.4.3  Thermometer  of range 0 - 110 ºC 
A.5 Preparation of  standar d hard water  
Dissolve 0.220 g of calcium chloride  dihydrate  and 0.246 g of magnesium sulphate heptahydrate  in distilled  
water. Dilute to 5 L with distilled water . 
NOTE  This standard hard water has a hardness of approximately 50 ppm calculated as ca lcium ca rbonate.  
A.6 Procedure   
A.6.1  Weigh 1 g of the hand  wash  accurately in a 100 -ml glass beaker. Add 10 ml of the standard ha rd water. 
Cover the beaker with a watch glas s and allow to stand for 30 min. The operation is carried out to disperse the 
hand  wash .  
A.6.2  Stir the contents of the beaker with a glass rod a nd transfer the slurry to a 250 -ml graduated cylinder  
ensurin g that not  more than 2 ml foam is produced. Repeat the transfer of the residue left in the beaker with 
further portions of 20 ml of standard h ard wate r ensuring that all the matter in the beaker is transferred to the 
cylinder.  
A.6.3  Adjust the contents i n the cy linder t o 100 ml by adding sufficient standard hard wat er. Bring the contents 
of the cylinder to 30  ºC. Stir the contents of the cylinder with  a glass  rod or thermometer to ensure a uniform 
suspension.  
A.6.4 As soon as the temperature of the co ntents of  the cyli nder r each 30  ºC, stopper the cylinder and give it 
12 complete inversions, each inversion comprising movements in a vertical plane, upside dow n and vi ce 
versa. After the 12 inversions, let the cylinder stand for 5 min. Take the following readi ngs as shown in Figure 
A.1: 
a) foam plus water (V 1 ml). 
b) water o nly (V 2 ml).  
© EAC 2022 – All rights reserved  5 
 
 
Figure A.1 — Measurement of foam  
A.7 Calculation  
Lather volume = V1 - V2 
where 
 V1 = Volume, in ml of foam + water;  
 V2 = Volume, in ml of water only.  
  
6 © EAC  2022 – All rig hts reserved  
 Annex B  
(normative)  
 
Determi nation of active detergent content  
B.1 Outline of the method  
When equivalent amounts of cationic and anionic detergents are present in a two -phase mixtu re of wa ter and 
chloroform, methylene blue will colour the two p hases to the same degree. Sodium alkyl b enzene sul phonate and 
sodium lauryl sulphate or any other deter gent can be titrat ed with a standard solution of cetyl trimethyl ammonium 
bromide.  
B.2 Reagents  
Weigh 1.5 ± 0.001 g of cetyl trimethyl ammonium brom ide into a 250 ml beaker. Add 100 ml of disti lled w ater 
and stir until dissolved. Transfer quantitatively to  a 1 litre volume tric flask and make to volume. Mix thoroughly 
and s tandardize against so lution B . (See B.2.1). 
B.2.1 Anionic solution (Solution B)  
Weigh accurately such amount of standard alk yl sulpha te of known combined SO 3 or active content so as to 
give exactly 0.320 g of combined SO 3 into a 250 ml beaker.  Dissolve in 100 ml to 200 ml of warm wa ter.  
Transfer quantitatively to 1 -litre volumetric flask and make to volume with water at room temper ature. Mix 
thoroughly.  This is the primary standard agai nst whic h solution A, is standardized. Solution B is 0.004 N.  
B.2.2 Methylene blue indica tor  
Dissolve 0.1 g of meth ylene blue in 100 ml of water. Transfer 30 ml of thi s solution to a 1 -L flask. Add 500 ml 
of water, 6.8 ml of concentrated sulphuric acid, 5 0 g of sodium phosphate (NaH 2PO 4H2O) and sha ke until 
solution is complete. Dilute to the mark.  
B.2.3 Chloroform  
Analytical reagent grade  
B.3 Procedure  
B.3.1 Weigh accurately a sample of suffic ient size to give approximately 0.320 g of combined SO 3 into a 250 
ml beaker. Samp le size is crucial (see Note). Use 700 ml to 800 ml of warm water to t ransfer quantitatively to 
a 1-L volumetric flask. Warm on steam bath and shake gently until the sample i s dissolve d and solution is 
clear. Cool, dilute to the mark and  mix thoroughly.  
NOTE  The titration value V should be as near as to 10 ml as possible, sa y betwee n 8 ml and 12 ml but never outside 
5 ml and 15 ml. 
B.3.2 Pipette 10.0 ml of the sample solution into a 100  ml glass sto ppered cylinder (25 x 300 mm). Add 25.0 
± 0.5 ml of methylene blue solution and 10 ± 0.5 ml of chloroform (see Note). Titrate wit h soluti on A to the 
correct end point, shaking the cylinder carefully after such addition to avoid emuls ion and ma intaining 
temperatu re within prescribed limits of 20 C - 30 C by immersion in water bath, if necessa ry. As the end 
point is approached, the rate of transfer of colour increases and solution A shall be added dropwise with 
vigorou s shaking after each addit ion. If the approximate titration is known, before sh aking since this avoids 
emulsion formation.  
Application of vacuum to the titration cylind er may h elp to break some emulsions, if formed. The end point is 
reached when both laye rs have same colo ur intensi ty. The end point is very sharp and 0.05 ml will caus e a 
distinct change in colour distribution at or near the equivalence point.   
© EAC 2022 – All rights reserved  7 
 NOTE  The tit ration v alue V should be as near to 10 ml as possible, say between 8 ml and 12 ml but never outside 5 
ml and 15 ml. 
B.3.3 Pipette 10.0 ml of the sample solution into a  100-ml glass stoppered cylinder (25 x 300 mm).  Add 25.0 
ml ± 0.5 ml of chloroform (see N ote). Titrate with solution A to the correct end point, shaking the cylinder 
carefully after such additi on to avoi d emulsion and maintaining temperature within prescri bed limits of 20  ºC to 
30 ºC by immersion in water bath if necessary. As the end point solution  A shall be added dropwise with 
vigorou s shaking after each addition. If the approximate titrati on is known, 8 0 % of the required titrating 
solution should be added before shaking since this avoids emulsion formation.  
Application of vacuum to the titra tion cyl inder may help to br eak some emulsions, if formed. The end point is 
reached when both laye rs have same col our intensity. The end point is very sharp and 0. 05 ml will cause a 
distinct change in colour distribution at or near equivalence point.  
NOTE  The volu me of methylene blue solution and chloroform may be changed if found advantageous provided t he 
same volume s are used in standardizing solutions A and B.  
B.3.4 Calculation  
B.3.4.1  The percent combined SO 3 shall be expressed as follows:  
% combined SO 3 =  
MNV 8.0 x   x  
where,   
V     volume, in millilitres,  of solution A used in the titrat ion; 
N     normality of solution A; and  
M     mass, in g rams,  of the sample in the aliquot.  
B.3.4.2  The percent active detergent content shall be expressed  as follo ws: 
Percent active detergent content = per cent combined SO 3 x Mol. weight of active detergen t. 
NOTE The mo lecular weight of active detergent should  be supp lied by the manufacturer on request.  
B.4 Alternative method for determination of active dete rgent con tent 
(To be used only if the first method ( Clause B.1 ) fails to work on the product).  
B.4.1 Field of appli cation  
This method is applicable to the analysis of alkylbenzene sulphonates, alkyl sulphonate, sulphates and 
hydroxy -sulphates, alkylphenol and fatty alcohol ethoxysulphates and dialkyl sulphosuccinates and to the 
determination of active mat erials contain ing one hydrophilic group per molecule.  
B.4.2 Principle  
Determination of anionic -active matter in a medium consisting of an aqueous and chlor oform pha se, by 
volumetric titration with a standard cationic -active solution (benzethonium chloride) , in the prese nce of an 
indicator which consists of a mixture o f a cationic dye (dimidium bromide) and an anionic dye (acid blue 1).  
B.4.3 Reagent s 
B.4.3.1 The wate r used shall be of distilled quality.   
8 © EAC  2022 – All rig hts reserved  
 B.4.3.2 Chloroform, (sp. gravity = 1.48 g/m, distillin g between 59.5ºC and 61.5 ºC). 
B.4.3.3 Sulphuric acid, 2.5 M sol ution.  
B.4.3.4 Sulphuric acid, 0.5 M solution.  
B.2.3.5  Sodium hydroxide, 1.0 M standard volu metric so lution.  
B.4.3.6 Sodium lauryl sulphate (sodium dodecyl sulphate) CH₃(CH₂)₁₁OSO₃Na 0.004  M standard 
volumetric solution.  
Check the purity of the sodium lauryl sulphate and simultaneously prepare the standard solution.  
B.4.3.6.1  Determination  of purity of sodium lauryl sulphate — Weigh to the nearest 1 mg, 5  g ± 0.2 g of the 
product into a 250 -ml round bo ttom flask with ground glass neck. Add exactly 25 ml of the sulphuric acid 
solution (B. 4.3.4) and reflux into a water condenser.  
During the f irst 5 mi n - 10 min, the solution will thicken and tend to foam strongly; control this by removing the 
source of he at and swirling the contents of the flask.  
In order to avoid excessive foaming, instead of refluxing the solution may be left on a boiling wa ter bath for 60 
min. 
After a further 10 min the solution clarifies and foaming cea ses. Reflux for further 90 min. R emove the source 
of heat, cool the flask and carefully rinse the condenser with 30 ml of ethanol followed by water.  
Add a few drops of the ph enolphtha lein solution (B. 4.3.8) and titrate the solution with the sodium hydroxid e 
solution (B. 4.3.5).  
Carry out a blank test by titrating 25 ml of the sulphuric acid solution (B. 4.3.4) with the sodium hydroxide 
solution (B. 4.3.5).  
The purity of the sodiu m lauryl sulphate, expressed as a percentage,  
1O O 1   ) ( 28.84
MM VV−=  
 
where,  
V0 =  volume, in millilitres, of sodi um hydroxide solution used for the blank  test; 
V1  = volume, in millilitres, of sodium hydroxide solution used for the sample;  
m1 = mass,  in grams , of the sodium lauryl sulphate to be checked; and  
M0   = exact molarity  of the sodium hydroxide solution . 
B.4.3.6.2  Weigh 0.004 M sodium lauryl sulphate  standard volumetric solution s. Weigh, to the nearest 1 mg 
between 1.14 g and 1.16 g of sodiu m lauryl sulphate an d dissolve in 200 ml of water. Transfe r to a ground 
glass stop pered 1-L volumetric fl ask and dilute to the mark with  water.  
Calculate the molarity, M 1, of the solution by means of the solution by means of the formula:  
100 x 288.4(%)  x   2
1purity m   M=
 
where,   
© EAC 2022 – All rights reserved  9 
 m2 = mass in grams of sodium lauryl sulphate.  
B.4.3.7 Benze thonium chloride 0.004 M standard  volumetric solution  
Weigh, to the nearest 1 mg, between 1.75 g and 1.85 g benzethonium chloride and dissolve in water.  Transfer 
to a groun d glass -stoppered 1-L volumetric flask and dilute to the mark with water.  
NOTE In order to prepare a 0.004 M solution, dry the benzethonium chloride at 105EC, weigh 1.792 g, to the nearest 
1 mg, dissolve in water and dilute to 1 L. 
B.4.3.8 Phenolph thalein, ethanol ic solution containing 10 g/L.  Dissolve 1 g of phenolphthalein in 100 ml of 
95 % (v/v) ethanol.  
B.4.3.9 Mixed indicator  
B.4.3.9.1 Stock solution  
Weigh to the nearest 1 mg 0.5 g ± 0.005 g dimidium bromide into a 50 -ml beaker, and 0.025  g ± 0.005 g of 
acid blue 1 into a second 50 -ml beaker.  
Add between 20 ml and 30 ml of hot 10 %. (v/v) ethanol to each beaker. Stir until dissolved and transfer the 
solutions to a 250 -ml volumetric flask. Rinse the beakers into the volumetric flask wi th ethano l and dilute to the 
mark with 10 % (v/v) ethanol.  
B.4.3.9.2 Mixed acid indicator solution  
Take 20 ml of the stock solution prepared above, put it in a 500 -ml volumetric flask. Add 200 ml of water, and 
20 ml of 2.5 M sulphuric acid (B. 4.3.3) mix a nd dilute to the mark with water. Store away from  direct sunlight.  
B.4.4 Apparatus 
Ordinary Laboratory app aratus, and   
a) bottles, 200 -ml, glass stoppered, or measuring cylinders, flask stoppered.  
b) burettes, 25 -ml and 50 -ml. 
c) volumetr ic flask,  1-L capacity glass stoppered.  
d) pipette, 25 -ml. 
B.4.5 Procedur e 
B.4.5.1  Standardization of ben zethonium chloride solution  
By means of the pipette transfer 25 ml of the 0.004 M sodium lauryl sulphate solution to a bottle or measuring 
cylinder, a dd 10 ml of water, 15 ml of the chloroform and 10 ml of the mix ed indicat or solution.  
Titrate with the 0.0 04 M b enzethonium chloride solution. Stopper the bottle or measuring cylinder after each 
addition and shake well. The lowe r layer will be col oured pin k. Continue the titration w ith repeated vigorous 
shaking. As th e end poin t approaches, the emulsions forme d durin g shaking tend to break easily c ontinue the 
titration drop by drop.  Shaking after each addition of titrant, u ntil the end point is rea ched. This is at the 
moment when the pink colour is completely discharge d from the  chloroform layer, which becomes a faint 
greyish blue.  
The molarity, M, of the benzethonium chloride solution is given by the formula:   
10 © EAC  2022 – All rig hts reserved  
 
2125 x   VM   M= 
where,  
M1   molarity of the sodium lauryl sulphate solution; and  
V2   Volume, in mollol itres, of benzethonium chloride added.  
B.4.5.2 Determination   
Weigh to th e nearest 1 mg a sample of 30 g;  dissolve the test portion in water.  Add a few drops of the 
phenolphthalein sol ution and  neutralize to a faint pink colour with the sodium hydroxide so lution or sulphuric 
acid solution as requir ed. 
Transfer to a 1 -L volumetric flask and dilut e to the mark with water.  Mix thoroughly and, by means of the 
pipette transfer 25 ml of this solution to a bottle or measuring cylinder, add 10 ml of water,  and add 1 0 ml of 
water, and 15 ml of chlor oform. Titrate with the benzethonium chloride solution as described in B. 4.5.1. 
B.4.6 Expression of results  
The content as a percentage by mass, of an ionic-active matter  
oo 3
 x 000  1 x 25100x  x 000  1  x  x  
MM M V=
 
=4V3M 
The amount o f active m atter, expressed in milliequivale nts per gram,  
o1 3 x  x 40
MM V=
 
where,  
M0   mass, in grams, of the test portion;  
M   relative molar mass of anionic -active matter;  
M1   molarit y of the benzethonium chloride solution;  
V3   volume, in millil itres, of benzethonium chloride solution u sed for the titration of a 25 -ml aliquot of 
anionic -active matter solution.  
 
 
 
  
© EAC 2022 – All rights reserved  11 
  
Annex C 
(norma tive) 
 
Sampling  
C.1 Procedure  
C.1.1 In a single consignme nt, all packages (cartons) containing toilet soap cakes drawn f rom the sa me 
batch of production shall constitute a lot. For ascertaining the conformity of the lot to the requirements of this 
standa rd, tests shall be carried out on  each lot separately. The number of packages to be selected for drawing 
the sample shall be in acco rdance with Table C.1.  
Table C.1 — Scale of sampling  
Number of packages (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 
 
C.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 pack age, 
where k is the integral part of N  n.  
C.1.3 From each package thus selected, draw at random an equal number of bottles so as to obtain a total 
volume  of at least 2 L.  
C.2 Preparation of test s amples  
C.2.1 Composite sample  
Weigh each cake separately (incl uding any material that may have adhered to the wrapper), and calculate the 
average mass. Cut each of the remaining cakes into eight par ts by means of three cuts at right angles to each 
other t hrough t he middle. Grate finely the whole of two diagonally opp osite eigh ths of each specimen. Mix the 
gratings and place in a clean, dry, airtight glass container.  
C.2.2 Samples for testing  
Immedia tely after preparation of composite sample ( C.2.1), take at one tim e all test samples required for the 
tests in 4.2. Wei gh out the  test sample required for determination of free alkali or acid content, and use it 
immediately.  
 
  
12 © EAC  2022 – All rig hts reserved  
 Bibliography  
EAS 812 -1:2013 Liquid hand wash — Specification — Part 1: Synthetic and combined (soap and synthetic) 
hand  wash.