DEAS  338: 2020  
ICS 71.100.70  
 
© EA C 2020                                                                                                                               3rd Editio n 2020   
 DRAFT EAST AFRICAN STANDARD  
Chemical hair relaxers and hair waving products — Specification  
EAST AFRICAN COMMUNITY  DEAS  338: 2020  
ii © EAC 2020  – All rights reserved  
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Reproduction for sales purposes may be subject to royalty payments or a licensing agreement.  
Violators may be prosecuted . DEAS  338: 2020  
© EAC 2020  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative ref erences  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Types  ................................ ................................ ................................ ................................ ......................  2 
5 Requirements  ................................ ................................ ................................ ................................ .........  2 
5.1 General requirements  ................................ ................................ ................................ ...........................  2 
5.2 Specific requirements  ................................ ................................ ................................ ...........................  2 
5.3 Heavy metal contam inants  ................................ ................................ ................................ ...................  3 
5.4 Microbiological limits  ................................ ................................ ................................ ............................  3 
6 Packaging  ................................ ................................ ................................ ................................ ...............  4 
7 Labelling  ................................ ................................ ................................ ................................ .................  4 
8 Sampling  ................................ ................................ ................................ ................................ ................  5 
Annex A  (normative)  Determination of free alkali content  ................................ ................................ ...........  6 
A.1 Outline of the method  ................................ ................................ ................................ ...........................  6 
A.2 Reagents  ................................ ................................ ................................ ................................ ................  6 
A.3 Procedure  ................................ ................................ ................................ ................................ ...............  6 
A.4 Calcula tion ................................ ................................ ................................ ................................ .............  6 
Annex B  (normative)  Determination of total alkali content  ................................ ................................ ..........  8 
B.1 Outline of the method  ................................ ................................ ................................ ...........................  8 
B.2 Reagents  ................................ ................................ ................................ ................................ ................  8 
B.3 Apparatus  ................................ ................................ ................................ ................................ ...............  8 
B.4 Procedure  ................................ ................................ ................................ ................................ ...............  8 
B.5 Calculation  ................................ ................................ ................................ ................................ .............  8 
Annex C  (normative)   Determination of thioglycollic acid  ................................ ................................ .........  10 
C.1 Reagents  ................................ ................................ ................................ ................................ .....................  10 
C.1.1 Concentrated hydrochloric acid  ................................ ................................ ................................ ............  10 
C.1.2 Standard iodine solution, 0.1 N  ................................ ................................ ................................ .............  10 
C.2 Procedure  ................................ ................................ ................................ ................................ ...................  10 
C.3 Calculation  ................................ ................................ ................................ ................................ ..................  10 
Bibliography  ................................ ................................ ................................ ................................ ......................  11 
 DEAS  338: 2020  
iv © EAC 2020  – 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 C ommunity will be removed.  
The Community has established an East African Standards Committee  (EASC)  mandated to develop and 
issue East African Standards  (EAS) . The Committee is composed of representatives of the National 
Standards Bodies in Partner States,  together with the representatives from the public and private sector 
organizations  in the community .  
East African Standards are developed through  Technical Committees that are representative of key 
stakeholders including government, academia, consumer gr oups, private sector and other interested parties. 
Draft East African Standards are circulated to stakeholders through the National Standards Bodies in the 
Partner States. The comments received are discussed and incorporated before finalization of standard s, in 
accordance with the Principles and procedures for development of East African Standards.  
East African Standards are subject to review, to keep pace with technological advances. Users of the East 
African Standards are therefore expected to ensure tha t they always have the latest versions of the standards 
they are implementing .  
The committee responsible for this document is Technical Committee EASC/TC 071, Cosmetics and related 
products.  
Attention is drawn to the possibility that some of the elements of this document may be subject of patent 
rights. EAC shall not be held responsible for identifying any or all such patent rights.  
This third edition cancels and replaces the second edition ( EAS 338:2013 ), which has been technically 
revised.  
 DRAFT EAST AFRICAN STANDARD  DEAS  338:2020  
 
© EAC 2020  – All rights reserved  1 
 Chemical hai r relaxers and hair waving products — Specification  
1 Scope   
This Draft East African Standard specifies the requirements, sampling and methods of test for chemical hair 
relaxers and hair waving products.  
This standard applies to chemical  hair relaxers based on alkalis or thioglycollates, as well as hair waving 
(curling) products based on thioglycollates.  
2 Normative references   
The following documents are referred to in the text in such a way that some or all of their content constitutes 
requirements of this document.  For dated re ferences, only the edition cited applies. For undated references, 
the latest edition of the referenced document (including any amendments) applies.  
 
EAS 346 , Labelling of cosmetics — General requirements  
EAS 377 (all parts), Cosmetics and cosmetic products  
EAS 847 -16, Cosmetics —Analytical methods —Part 1 6: Determination of lead, mercury  and arsenic content  
EAS 847 -17, Cosmetics —Analytical methods —Part 17: Determination of pH  
EAS 847 -18, Cosmetics —Analytical methods —Part 18: Determination of thermal stability  
ISO 18416, Cosmetics —Microbiology —Detection of Candida albicans  
ISO 21149 , Cosmetics --Microbiology --Enumeration and detection of aerobic mesophilic bacteria  
ISO 22716, Cosmetics — Good Manufacturing Practices (GMP) — Guidelines on Good Manufacturing 
Practices   
ISO 22717, Cosmetics —Microbiology —Detection of Pseudomonas aeru ginosa  
ISO 22718, Cosmetics —Microbiology —Detection of Staphylococcus aureus  
ISO 24153,  Random sampling and randomization procedures  
3 Terms and definitions   
For the purposes of this document, the terms and definitions given in EAS 846 and the following a pply.  
ISO and IEC maintain terminological databases for use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp   
2 © EAC 2020  – All rights reserved  
 3.1  
lye based  
chemical hair relaxers that contain sodium hydroxide  
3.2 
no lye  
chemical hair relaxers that contain alkalis other than sodium hydroxide such as potassium hydroxide, lithium 
hydroxide, calcium hydroxide  
3.3 
thioglyco late based  
relaxer containing ammonium thioglycolate”  
4 Types  
Chemical hair relaxers and waving products shall be grouped into three categories, namely:  
a) lye-based;  
b) no lye; and  
c) thioglycollate -based  
5 Requirements  
5.1 General requirements  
5.1.1  Chemical hair relaxers and waving products shall comply with the requirements specified in all parts 
of EAS 37 7. 
5.1.2  The products shall be in the form of emulsions or gels.  
5.1.3  These products shall be homogenous and of uniform colour, with no visible signs of separation nor 
visible impurities.  
5.1.4  The product shall be manufactured in accordance with  the requ irements of  ISO 22716 . 
 
5.2 Specific requirements  
5.2.1 The lye and no lye relaxers (Type 1 and Type 2) shall, in addition, comply with the requirements given 
in Table 1 when tested in accordance with the methods indicated therein.   
© EAC 2020  – All rights reserved  3 
 Table 1 — Specific requirements for lye and no lye chemical h air relaxers  
S.No.  Characteristic  Requirements  Method of test  
i pH range  9- 14 EAS 847 -17 
ii Thermal stability  To pass the te st EAS 847 -18 
iii 
 Free alkali content, % by mass, max  2.5 Annex A 
iv Total alkali content: % by mass, max  
 Potassium hydroxide (KOH) - 2.5  Annex B 
Sodium hydroxide (NaOH) -2.5 
Lithium hydroxide (LiOH) -2.5  
Calcium hydroxide Ca (OH) 2 -7.0 
Ammonium hydroxide (NH 4OH) -6.0 
 
5.2.2 The thioglycollate based hair relaxers and hair waving products shall, in addition, comply with the 
requirements given in Table 2 when tested in accordance with the methods indicated therein.  
Table 2 — Specific r equirements for thioglycollate based hair relaxers and hair waving products  
S.No.  Characteristic  Requirements  Method of test  
Thioglycollic acid and 
its salts  Thioglycollic acid 
esters  
i pH range  7- 9.5 6-9.5 EAS 847 -17 
ii Thioglycollic 
acid, %, max  
 General use  8 8 Annex C 
Professional 
use 11 11 
 
5.3 Heavy metal contaminants  
The products shall comply with the limits for heavy metal contaminants in accordance with Table 3. 
Table 3 — Heavy metal limits for  chemical hair relaxers and hair waving products  
S.No  Characteristic  Limits , mg/k g, max  Method of test  
i Lead  10 EAS 847 -16 
ii Arsenic  2 
iii Mercury  2 
NOTE The total a mount of heavy metals as lead, mercury and arsenic, in combination, in the finished product should not 
exceed 10 Mg/kg. 
 
5.4 Microbiological limits  
The hair relaxers and hair waving products shall also comply with the microbiological limits given in Table 4 
when tested in accordance with the methods indicated therein.   
4 © EAC 2020  – All rights reserved  
  
Table 4 — Microbiological limits for hair relaxers and hair waving products  
S/No  Micro -organisms  Limits,  
Cfu/g  Method of test  
I Total viable count for aerobic 
mesophyllic microorganisms 
CFU/ml, max.  
 100 
 
 ISO 21149  
Ii Pseudomonas aeruginosa  Not detected  in 1 ml or 1 g of 
cosmetic product  ISO 22717  
 
ISO 22718  
 
ISO 18416  Iii Staphylococcus aureus  
Iv Candida albicans  
v Escherichia coli  Not detected in 1 g of cosmetic 
produc t ISO 21150  
 
6 Packaging  
The product shall be packaged in suitable well -sealed containers that shall protect the contents and shall not 
cause any contamination or react with the product.  
7 Labelling  
In addition, to the labelling requirements given in EAS 346, each package shall be legibly and indelibly marked 
with the following  information  (an enclosed leaflet may also  be used):  
a) category of product as follows:  
i. mild — for fine textured or processed hair;  
ii. regular — For medium textured hair;  
iii. super — For coarse hair;  
 
b) type of alkali used;  
c) instructions for use including the neutralising shampoo and conditioner which are recommended for use 
with the product;  
d) precautions/warnings:  
i. for products containing thiogl ycollic acid, its salts and its esters, the warnings include:  
 For professional use only;  
 Contains thioglycollate;  
 Follow the instructions;  
 Avoid contact with eyes;  
 In the event of contact with eyes, rinse immediately with plenty of water and seek 
medi cal advice;  
 Wear suitable gloves; and  
 Keep out of reach of children.   
© EAC 2020  – All rights reserved  5 
 ii. for lye -based and no lye relaxers, the warnings include:  
 for professional use only;  
 contains alkali;  
 keep out of reach of children;  
 follow the instructions;  
 wear suitable glov es;  
 avoid contact with eyes as the product can cause blindness; and  
 in the event of contact with eyes, rinse immediately with plenty of water and seek 
medical advice.  
8 Sampling  
Sampling shall be carried in accordance with ISO 24153 .  
6 © EAC 2020  – All rights reserved  
 Annex A  
(normative ) 
 
Determination of free alkali content  
A.1 Outline of the method  
This method consists of dissolving the sample in alcohol, and titrating against standard acid.  
A.2 Reagents  
A.2.1 Phenolphthalein indicator solution , dissolve 1 g of phenolphthalein in 100  mL of 95 % (v/v) rectified 
spirit.  
A.2.2 Ethyl alcohol, freshly boiled, and neutral to phenolphthalein, 95 % (v/v)  
A.2.3 Standard hydrochloric acid, 0.1 N  
A.3 Procedure  
Dissolve 2 g of hair relaxer in 100 mL of ethyl alcohol by warming, if necessary. C ool and add a few drops of 
phenolphthalein indicator. Titrate with standard hydrochloric acid.  
A.4 Calculation  
The free alkali content shall be calculated as follows:  
Free alkali, % by mass = 
  
where  
C is a Con stant  
C = 2.4 for LiOH  
C = 4 for NaOH  
C = 5.6 for KOH  
C = 3.7 for Ca(OH)2  
C = 3.5 for NH4OH  
V is the volume, in millilitres, of standard hydrochloric acid;  
N is the normality of standard hydrochloric acid; and  
M is the mass, in grams, of th e sample   
© EAC 2020  – All rights reserved  7 
 Where mixtures of sodium, lithium and potassium hydroxide are present in the product, the free alkali content 
shall not exceed 2.5 % by mass when calculated as sodium hydroxide   
8 © EAC 2020  – All rights reserved  
 Annex B  
(normative)  
 
Determination of total alkali content  
B.1 Outlin e of the method  
The method consists of refluxing the sample in alcohol, and titrating with standard acid.  
B.2 Reagents  
B.2.1 Ethanol , 95 % (v/v) solution, free from carbon dioxide. Reflux this solution for 5 min. Cool to room  
temperature and neutralize wit h the ethanolic potassium hydroxide solution per 200 mL of ethanol.  
B.2.2 Hydrochloric acid , 1 N standard solution  
B.2.3 Ethanolic potassium hydroxide,  0.1 N ethanolic standard solution  
B.2.4 Phenolphthalein solution,  of 1 g per 100 mL in 95 % (v/v) ethano l 
B.3 Apparatus  
B.3.1 Conical flask capacity 250 mL , with a conical ground -glass joint at the bottom  
B.3.2 Reflux condenser , water cooled, with a conical ground -glass joint at the bottom  
B.3.3 Analytical balance  
B.4 Procedure  
B.4.1 Weigh accurately 2 g of the sample into the flask. Add 100 mL of the ethanol solution to the test 
portion. Fit  the flask to the reflux condenser, and gently heat until the sample is completely dissolved.  
B.4.2 Add 3.0 mL of the hydrochloric acid solution and boil gently for 10 mi n. If after boiling, the pink colour 
reappears,  
B.4.3 add a further quantity of hydrochloric acid. Titrate, at 70 °C, with the ethanolic potassium hydroxide  
solution in the presence of phenolphthalein indicator. Carry out two determinations on the same sample.  
B.5 Calculation  
The total alkali content shall  be calculated as follows:  
 
  
© EAC 2020  – All rights reserved  9 
 where  
C is a Constant  
C = 2.4 for LiOH  
C = 4 for NaOH,  
C = 5.6 for KOH  
C = 3.7 for Ca(OH) 2 
C = 3.5 for NH 4OH 
V0 is the volume, in millili tres, of hydrochloric acid used;  
V1 is the volume in millilitres of potassium hydroxide used in titration ; 
N0 is the exact normality of hydrochloric acid;  
N1 is the exact normality of the potassium hydroxide s olution used ; and. 
M is the mass, in grams, of the sample.  
Where mixtures of sodium, lithium and potassium hydroxide are present in the product, the total alkali content 
shall not exceed 2.5 % by mass, calculated as sodium hydroxide.   
10 © EAC 2020  – All rights reserved  
 Annex C  
(normative)   
 
Determination of thioglycollic acid  
C.1 Reagents  
C.1.1 Concentrated hydrochloric acid  
C.1.2 Standard iodine solution, 0.1 N  
C.2 Procedure  
Accurately weigh about 5 g of the sample in a 250 mL conical flask. Add about 75 mL of water and 15 mL of  
concentrate d hydrochloric acid and heat on a water bath for 10 min. Cool and titrate with iodine solution using  
starch solution as the indicator.  
C.3 Calculation  
Calculate on the basis that each ml of 0.1 N iodine solution is equivalent to 0.00921 g of thioglycollic acid.  
% of thioglycollic acid, m/m 
  
where  
M is the mass, in grams, of sample taken for test; and  
V is the volume, in millilitres, of 0.1 N iodine solution used   
© EAC 2020  – All rights reserved  11 
 Bibliography  
EAS 338: 2013 , Chemical hair relaxers and hair waving products — Specification  
 DEAS  338: 2020    
 
© EAC 2021  – All rights reserved