KENYA STANDARD  DKS 1113 -4:2022 
ICS 59.080.20  
Second Edition  
 
 © KEBS 2022   
 Specification  for spun yarns  
Part 4: Polyester/ wool  blended  yarns  
 
 KENYA STANDARD  DKS 1113 -4:2022  
ICS 59.080.20  
Second Edition  
 
© KEBS 2022 – All rights reserved  ii 
 TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
Agriculture and Food Authority — Fibre Crops Directorate (AFA -FCD)  
Intertek International Ltd.  
Kenya Agricultura l & Livestock Research Organization (KALRO)  
Kenya Association of Manufacturers (KAM)  
Ministry of State Defence — Research and Development Department  
Moi University  
Ministry of Industrialization, Trade and Enterprise Development — State Department for Indus trialization — 
Directorate of Agro -Industries  
Technical University of Kenya — Department of Fashion, Clothing and Textiles  
Texfab B.S  
Nakuru Fibres Ltd.  
East African Fine Spinners Ltd.  
Nakuru Industries Ltd.  
Spin Knit Ltd.  
Kenya Consumers’ Organization  
Ministry of Public Works — Materials Branch  
Kenya Taitex Mills Ltd.  
Mount Kenya Textiles Ltd.  
Rift Valley Textiles Ltd.  
Spinners and Spinners Ltd.  
Ken-knit (K) Ltd.  
Raymond’s Woolen Mills (K) Ltd.  
Kenya Prisons —Tailor ing Division  
Bonar (E.A.) Ltd.  
Kenya Industrial Research and Development Institute (KIRDI)  
Kenya Bureau of Standards — Secretariat  
REVISION OF KENYA STANDARDS  
In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed.   Suggestions for 
improvements to published standards, addressed to the Managing Director, Kenya Bureau of Standards, are 
welcome.  
© Kenya Bureau of Standards 2022  
Copyright. Users are reminded that by virtue of Section 25 of the Copyright Act, Cap. 130 of  2001 of the Laws of Kenya, copyright subsists 
in all Kenya Standards and except as provided under Section 25 of this Act, no Kenya Standard produced by Kenya Bureau of Sta ndards KENYA STANDARD  DKS 1113 -4:2022  
ICS 59.080.20  
Second Edition  
 
© KEBS 2022 – All rights reserved  iii 
 may be reproduced, stored in a retrieval system in any form or transmitted by  any means without prior permission in writing from the 
Managing Director.  
  KENYA STANDARD  DKS 1113 -4:2022  
ICS 59.080.20  
Second Edition  
 
© KEBS 2022 – All rights reserved  iv 
 Specification  for spun yarns  
Part 3 : Polyester/ wool  blended yarns  
  Kenya Bureau of Standards, Popo Road, Off Mombasa Road,  
P.O. Box 54974 - 00200,  Nairobi, Kenya  
 +254 020 6948000, + 254 722202137, + 254 734600471  
 info@kebs.org  
 @KEBS_ke  
 kenya bureau of standards (kebs)  
KENYA STANDARD  DKS 1113 -4:2022  
ICS 59.080.20  
Second Edition  
 
© KEBS 2022 – All rights reserved  v 
 Foreword  
 
This Kenya Standard has been prepared by the Technical Committee on Yarns and Fibres under guidance of 
the Standards Projects Committee, and it is in accordance with the procedures of the Kenya Bureau of 
Standards.  
Yarn quality affects not only the effici ency of fabric production but also the fabric quality. Yarn quality 
specification will therefore be of utmost importance and interests to the spinner, weaver, knitter and yarn 
merchant. This standard has been developed with these interests in mind.  
Yarn i s produced in a wide range of linear densities (counts) of varying fibre blend compositions and proportions 
for various end -uses. This standard takes into consideration all these variations and specifies only the minimum 
requirements for the essential qual ity characteristics of yarns.  
This Second edition cancels and replaces the First edition (KS 1113 -3:1993) which has been technically 
revised. The changes are as follows.  
               -Test methods in clauses 5.1, 5.2, 5.3, 5.4, 5.5, 5.6 and 5.7  have bee n updated  
               -Formular for coefficient of variation of linear density has been added  
               -Clause 7 on sampling have been added  
               -Method of determination of moisture regain  have been added in annex A  
 
During the preparat ion of this standard, reference was made to the following document:  
KS 1113 -4:1999 Specification for staple spun yarns Part 4. Polyester/ wool blended yarns  
The wira textile data book.  
The wira textile data book.  
Acknowledgement is hereby made for the assistance received from these sources.DKS 1113 -4:2022   
 
© KEBS 2022 – All rights reserved   
 Specification  for spun yarns  — Part 4. Polyester/ wool  blended yarns  
1 Scope  
This Part 4 of KS 1113 specifies the requirements for polyester/wool blended yarns.  
 
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 references, only the edition cited applies. For undated references, the 
latest edition of the referenced document (including any amendments) applies.  
KS ISO 139,  Textiles — Standard atmos pheres for conditioning and testing  
ISO 1833 -4, Textiles — Quantitative chemical analysis — Part 4: Mixtures of certain protein fibres with certain 
other fibres (method using hypochlorite)  
KS ISO 2060, Textiles — Yarn from packages — Determination of linear density (mass per unit length) by the 
skein method  
KS ISO 2061, Textiles — Determination of twist in yarns — Direct counting method  
KS ISO 6741 -1, Textiles — Fibres  and yarns — Determination of commercial mass of consignments — Part 1: 
Mass determination and calculations.  
 
KS ISO 2062, Textiles — Yarns from packages — Determination of single -end breaking force and elongation 
at break using constant rate of extension (CRE) tester  
KS ISO 16549, Textiles — Unevenness of textile strands — Capacitance method  
 
3  Application  
This standard applies to singles -spun grey polyester/wool blended yarns, except single -spun fancy yarns  
4 Terms and definitions  
For the purpose of thi s standard, the definitions given in KS 1113: Part 1, apply.  
 
5 Requirements  
5.1 Fibre Composition and Proportion  
The fibre composition and proportion of the yarns shall be as declared, subject to a tolerance of ± 5 per cent. 
This shall be determined in accordance with KS ISO 18 33-4  
© KEBS 2022 – All rights reserved  iii 
 5.2 Linear density  
The nominal linear density of the yarn shall be as declared, subjec t to a tolerance of ± 3 per cent. This shall be 
determined in accordance with  KS ISO 2060  
5.3 linear density  variation  
The inter -package coefficient of variation of linear density of the yarn shall not exceed 2 per cent.  The coefficient 
of variation (C.V.)  of the yarns shall be determined using the following formula:  
C.V. =
%100 X 
x  
where  

12


nxx

 
where  
x is the linear density in tex of any yarn sample;  
x
 is the mean linear density in tex of all the yarn samples;  
n
 is the total number of samples; and  

 is the standard deviation in tex.  
5.4 Yarn twist  
The turns per metre (or centimetre) in the yarn shall be as decla red, subject to a tolerance of ± 5 per cent. This 
shall be determined in accordance with KS ISO 2061.  
5.5 Elongation at the breaking force  
The minimum elongation at breaking force shall be 10 per cent. This shall be determined in accordance with KS 
ISO 206 2. 
5.6 Breaking tenacity  
The minimum breaking tenacity of the yarn shall be 12 cN/tex. This shall be determined in accordance with KS 
ISO 2062.  
5.7 Yarn unevenness (irregularity)  
The yarn unevenness (irregularity) in terms of   C.V. per cent shall not exceed those specified in Table 1. The 
uster C.V. per cent shall be determined in  
accordance with  KS ISO 16549.  
 
  
© KEBS 2022 – All rights reserved  iv 
 5.8 Moisture regain  
The moisture regain of the yarn shall not exceed 10 per cent. This shall be determined in accord ance with Annex 
A. 
5.9 Package mass  
The mass of the package, conditioned as per KS ISO 139 , shall be as declared subject to a tolerance of – 2 per 
cent.   
 
 
Table 1. Requirements for Unevenness (Irregularities)   
  
 
S/N   
Range of Linear Density, 
tex    
Maximum  C.V.. %  
Test Method  
i.  Courser than 70  14.0 KS ISO 16549  
ii.  70-60 14.5 
iii.  59-50 15.0 
iv.  49-40 16.5 
v.  39-30 18.0 
vi.  29-20 19.5 
vii.  19-15 20.0 
viii.  14-12 21.0 
ix.  11-10 22.0 
x.  Finer than 10  23.5 
  
  
 
 
 
 
  
© KEBS 2022 – All rights reserved  v 
 6 Wrapping and packing  
Yarn package(s) shall be wrapped in suitable wrappers and/or packaged in suitable containers to protect 
them from damage during storage, handling or while on transit.  
7 Marking  
7.1 Unit Packages  — Each unit packages shall have a label bearing the following information:  
 
(a) Manuf acturer’s name , address  or registered trade mark;  
(b) Linear density, in tex;  
(c) Fibre composition and proportion;  
(d) Package net mass, in g or kg;  
(e) Country of origin  
 
7.2 Bulk Containers  — Each bulk container shall have a label bearing the follo wing information:  
 
a) Manufacturer’s name , address  or registered trade mark;  
b) Name of material, i.e. polyester/wool yarn;  
c) Linear density, in tex;  
d) Quantity of pieces;  
e) Gross mass of container, in kg or tonnes;  
f) Lot number /batch ; and  
g) Country of origin  
 
8 Sampling  
8.1 Lot  
 
8.1.1 The quantity of polyester /wool  spun yarns of the same variety delivered to a buyer against a d ispatch note 
shall constitute the lot.  
8.1.2 The conformity of the lot to the requirements of this standard shall be determined based on the tests 
carried out on the samples selected from the lot.  
8.1.3 Unless otherwise agreed to between the buyer and the seller, the number of packs to be selected at 
random from a lot shall be as follows:  
SN Number of Packs in the Lot  Number of Packs to be Selected  
i.  Upto 15  5 
ii.  16-30 7 
iii.  31-50 10 
iv.  51-100 15  
© KEBS 2022 – All rights reserved  vi 
 v.  101-300 25 
vi.  301 and above  30 
 
8.1.4 Acceptance criteria - Acceptance shall be based on conformity of the lot to the requirements of this 
standard.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
© KEBS 2022 – All rights reserved  vii 
 ANNEX A  
(Normative)  
Determination of Moisture Regain  
A.1 Principe  
A known mass of yarns is dried and then the loss in mass expressed as a ratio of the dry mass.  
 
A.2 Apparatus  
 A.2.1 Weighing balance , Capable of weighing to an accuracy of 0.001 g.  
A.2.2 Drying Oven , well ventilated with a temperature of 102 °C to 105 °C  
A.2.3 Desiccator , waterproof when sealed, will be used for transfer of analysed material and during weighing.  
 
 A.3 Procedure  
A.3.1  From the sample under test draw at least three test specimens each weighin g approximately 5 g.  
A.3.2 Take a test specimen drawn as in A.3.1 and weigh it accurately  (M1) 
A.3.3 Dry it at a temperature of 102°C to 105°C until constant mass is obtained (see note)  
A.3.4 Cool the test specimen in a desiccator and determine the oven -dry mass (M2).  
NOTE The mass is usually regarded as constant if the loss between two successive weighing, taken at an interval of 30 min does not 
exceed  0.1 per cent of the first of the two values.  
 
A.3.5  Similarly test the other test specimen(s).  
 
A.4 Cal culation  
Moisture regain = 
%100 
22 1X 
MM M  
A.5 Report  
 Report the average of the value calculated in A.4 as the moisture regain in %.