ii © KEBS 2023  – All rights reserved  
  
KENYA STANDARD  KS 2660  :2023 
ICS 55.080 
Second Edition  
 
 
 
 
Backpack bags — Specification   
   
 
 
 
  
  
 
 
 
 
 
 
KENYA STANDARD  KS 2660 :2023  
ICS 55.080  
Second  Edition  
  
© KEBS 2023  – All rights reserved  iii 
  TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
 
Egerton University  
Kirinyaga University  
Alliance Garments  
Bedi Investments  
Manchester Outfitters  
Spinners and Spinners Ltd.  
Consumer Information Network  
Kenyatta University  
Export Processing Zone Authority  
Kenya Medical Supplies Authority  
Kenya Shirts  
RIVATEX East Africa Ltd.  
Backpack Uniforms  
Manchester Outfitters  
Institute of Packaging Professionals of Kenya  
Institute of Packaging of Kenya  
Millbrook Garments  
Kenya Suitcase Manufacturers  
Kenya Industrial Research and Development Institute  
University of  Eldoret  
Intertek  
Moi university –Department of Industrial and Textile Engineering  
National Industrial Training Authority (NITA)  
Ministry of Industrialization and Trade  
Kenknit Eldoret Ltd  
Spinknit  Nakuru Ltd  
Technical University of Kenya(TUK)  
Spinknit L td Nakuru  
Egerton University — Department of Applied Community Development Studies  
PVH Corp  Ltd 
Kitale Wool Shop  
Mbagathi Hospital  
Kenya Association of Manufacturers(KAM)  
Kenya Bureau of Standards — Secretariat  
 
  
iv © KEBS 2023  – All rights reserved  
 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, 2023 
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 
may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing f rom the 
Managing Director.   KENYA STANDARD  KS 2660 :2023  
ICS 55.080  
Second  Edition  
  
© KEBS 2023  – All rights reserved  v 
   
 
 
Backpack bags — Specification  
 
 
   
 
 
 
  
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)  
  
 
vi © KEBS 2023  – All rights reserved  
 Foreword  
 
This Kenya Standard was prepared by the Technical Committee on Ready Made Garments under the guidance 
of the Standards Projects Committee, and it is in accordance with the procedures of the Kenya Bureau of 
Standards.  
 
 
This standard specifies performance requirements for back pack type of bags for various uses in offi ce schools, 
travelling and other business.  
 
This second edition of the standard cancels and replaces KS 2660:2016 which has been technically revised  
 
During the preparation of this standard the committee relied on data from samples from local manufacturer and 
retailers of Backpack bags  
 
Acknowledgement is hereby made for the assistance received from these sources   
  KS 2660 :2023   
 
© KEBS 2021– All rights reserved   
 1. Scope  
This Kenya Standard provides specifications, test methods and labelling requirements for backpack bags 
for use in schools, travelling, office and other business.  
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.  
 
 
KS ISO 3758, Textiles — Care labeling using symbols  
 
KS 2659, Packaging of textile products — Code of practice  
 
KS 479 -2, Sewing threads — Part 2: Sewing threads made wholly or partly from fibres  
 
KS ISO 3759, Textiles — Preparation, marking and measuring of fabric specimens and garments in tests 
for determination of dimensional change  
 
KS ISO 633 0,Textiles — Domestic washing and drying procedures for textile testing  
 
KS ISO 5077, Textiles — Determination of dimensional change in washing and drying  
 
KS ISO 3081, Textiles — Woven fabrics — Determination of mass per unit length and mass per unit area  
 
KS 665, Specification for textile labels  
 
KS ISO 1833 -1, Textiles — Quantitative chemical analysis  Part 1. General principles of testing  
 
KS ISO 1833 -11, Textiles — Quantitative chemical analysis  Part  11. Mixtures of cellulose and Polyester 
fibres (met hod using sulphuric acid)  
 
KS ISO/TR 11827, Textiles — Composition testing — Identification of fibres  
 
KS ISO 2076: Textiles — Man-made fibres — Generic names  
 
KS ISO 13935 -1, Seam Tensile properties, Part 1: Strip test  
 
KS ISO 13935 -2, Seam Tensile properties Part 2: Grab test  
 
EAS 223, Zippers — Specification of vertically oriented specimens  
 
KS ISO 6941, Textile fabrics —  Burning behavior — Measurement of spread properties of vertically 
oriented specimens  
 
KS ISO 6940, Textile fabrics — Burning beha vior — Determination of ease of ignition  
  
© KEBS 2023  – All rights reserved  iii 
  KS 12947 -2, Textiles — Determination of abrasion resistance of fabrics by the martindale method, Part 2: 
Determination of specimen breakdown  
 
KS 214 -3,Specifications for woven linings, Part 3:Woven lining for men’s  and boys apparel  
 
KS 376 -1, Flexible polyurethane (polyether) foams — Specification Part 1: Mattresses  
 
KS 628, Specifications for elastic webbings  
 
KS ISO 811, Textile fabrics — Determination of resistance to water penetration  
 
KS ISO 13934 -1,Textiles — Tensile properties of fabrics Part 1: Determination of maximum force and 
elongation at maximum force using the strip method  
 
KS ISO 105 B02, Textiles — Colour fastness,  Part B02: Determination of colour fastness to artificial 
light: Xenon arc fading lamp test 
 
KS ISO 105 B04, Textiles — Colour fastness Part B04: Determination of colour fastness to 
weathering:Xenon arc fading lamp test  
 
KS ISO 105 E04, Textiles — Tests for colourfastnes Part E04 Colour fastness to perspiration  
 
KS ISO 105 C10, Textiles — Colour fastness Part C10 Colour fastness to washing with soap or soap with 
soda  
 
KS ISO 105 E01, Textiles — Tests for colour fastness Part E01:Colour fastness to water   
 
KS ISO 105 X12, Textiles — Tests for colour fastness Part X12:Colour fastness  to rubbing  
 
KS 944 -1, Specification for woven bags (100 percent) for green tea leaves Part 1:Three dimensional type  
 
KS 2217 -3, Glossary of terms used in the education sector Part 3:Secondary Education  
 
KS ISO 3, Preferred numbers -Series of preferred numb ers 
 
3. Definitions  
 
For the purposes of this standard, the terms and definitions given below shall apply.  
 
3.1 backpack - is a bag with two shoulder straps and/or waist straps. It can be made from polyester, 
canvas, or any other textile material.  
 
4. Requirements   
4.1 Dimensions of Backpack bag in height, length and width shall be as declared subject to maximum 
tolerance of 1% when determined in accordance with Annex B  
4.2 The Backpack shall  have a face, back  and middle panels  shaped symmetrically.  
 
  
iv © KEBS 2023  – All rights reserved  
  
4.3 Shoulder Straps  
4.3.1 The shoulder straps may be padded for comfort and shall contain adjustable straps.  The 
adjustable straps shall be webbing material made out of synthetic fibres and comply with KS 628.  
4.3.2 Waist strap where provided shall be adjustable.   
4.3.3 The  shoulder straps  where provided with padding material shall  be secured with fabric  
enclosing a polyolefin or polyurethane expanded material that comply  with the requirements given 
in Table 1  
 
Table 1 — Requirements for padding material  
 
Sl No  Fibre type  Density  in  
kg/m3,   min.  Thickness  in 
mm, min.  Test Method  
i) Expanded polyolefin  19 5 KS 376 -1 Annex 
B ii)   Polyurethane foam  19 5 
 
4.4 Closure  
 
Other types of closures can be used and where zippers have been used shall comply with the physical 
requirements in Table 2 in terms of grade and tensile strength characteristics.  
 
4.5 Fiber  composition and proportion of fabric  
 
4.5.1 The  fiber for making the fabric for panels shall be declared subject to maximum tolerance of ± 5 
% when tested in accordance with KS ISO 1833.  
 
4.6 Physical requirements  
 
4.6.1 The bag shall comply with the following physical characteristics as specified in Table 2 when 
tested with methods prescribed therein.  
 
Table 2 — Physical requirements  
 
Sl No  Parameter  Requirement  
 Test Method  
 
i.  Tensile strength in 
N, min  Warp  445 KS ISO 13934 -
1 Weft 287 
ii.  Tear resistance in N, 
min Warp  63 KS ISO 13937 -
1 Weft 52 
iii.  Seam strength in N, min   
 
235 KS ISO 13935 -
1 
iv.   
Strap pulling strength in N, 
min. Top 425 Annex A  
Bottom  330 
v.  Water resistance, cm head of water, min.  150 KS ISO 811   
© KEBS 2023  – All rights reserved  v 
  vi.  Abrasion resistance, number of rubs, min.  1250  KS ISO 12947 -
2 
vii.  
 Strap joint strength in N, min.  365 Annex A  
viii.  Seam slippage, at 3 mm 
opening, load in N, min.  Warp  100 KS ISO 13936 -
2 Weft 100 
ix.  Stitches per cm  2-3 Annex C  
 
x.  Mass in g/m2, min.  330 EAS 
KS ISO 3801  
xi.  Drop test based on 3 -10 kg load, at 1 metre 
height  Pass  Annex D  
xii.  Top handle attachment strength, in N, min,  305 KS 944 -1 
xiii.  
 
 
 
 
 
 
 
xiv.   
 
 
 
 
 
 
 
Physical requirements of zippers, in N, min.  Puller attachment  200 EAS 223  
Closed end test  80 EAS 223  
Top stop test   
90 EAS 223  
Open end 
fastener box test  90 EAS 223  
Lateral strength 
test 250 EAS 223  
Lateral strength of 
open end  90 EAS 223  
Slider locking test  25 EAS 223  
 
4.7 Colorfastness requirements  
 
4.7.1The Backpack bag shall comply with the following colour fastness requirements as specified in 
Table 3  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
vi © KEBS 2023  – All rights reserved  
 Table 3 — Colour fastness requirements  
 
Sl No  
 Agency  Rating, min.  Test Method  
1 Light  5 KS ISO 105 B02  
2 Weathering  5 KS ISO B04  
3  
Perspiration  Acid Colour 
Change   
 
4 
  
KS ISO 105 E04  
Staining  
Alkali  Colour 
change  
Staining  
4 Washing  Colour change  4 KS ISO 105 C10  
Staining  4 
5 Water  Colour change  4 KS ISO 105 E01  
Staining  4 
6 Rubbing  Wet 4 KS ISO 105 X12  
Dry 3-4 
 
 
4.8 Restricted colorants  
 
Where colorants have been applied on the bags, the dyed fabric shall not contain dyestuffs specified in KS 
ISO 16373 -2 and KS ISO 16373 -3 and KS ISO 24632, Parts 1 and 3 and pthalates detected and quantified 
in accordance with KS ISO 14389 shall not be more than  0.1 % by mass.  
 
5 Packaging  
 
The unit and bulk packages of Backpack bags shall comply with requirements of KS 2659.  
 
6 Marking  
 
6.1  Unit packages  
 
The following information shall be marked legibly and indelibly on a label affixed on each bag  
 
a) Manufacturer's name or registered trade mark;  
b) Fibre type and content;  
c) Dimensions of bag in height, length and width   
e)  Care instructions in accordan ce with KS ISO 3758;  
 
 
 
 
 
 
 
 
 
  
© KEBS 2023  – All rights reserved  vii 
  Annex A  
(normative)  
 
Determination of strap  assembly strength  
 
A1 Top strap attachment strength  
 
A 1.1 Extract and Mount a specimen, with the strap fixed at the top jaw and the bag fabric part fixed at 
the bottom jaw ensuring that the top strap attachment seam is clear from the bottom jaw line and the 
specimen length is at least 30 cm to comply with a gauge length of 20 cm.  
 
A 1.2  Determine the top strap attachment strength as the seam tensile strength of the specimen  in 
accordance with KS ISO 13935 -1. 
 
A 2  Bottom strap attachment strength  
 
A2.1 Extract and mount a specimen, with the bottom strap (webbing) fixed at the top jaw and the bag 
fabric part  fixed at the bottom jaw of a tensile testing machine ensuring that the bottom strap (webbing) 
attachment seam is clear from the bottom jaw line and t he length of the specimen is at least 30 cm to 
comply with a gauge length of 20cm.  
 
A 2.2  Determine the bottom strap (webbing) attachment strength as the seam tensile strength of the 
specimen in accordance with KS ISO 13935 -1. 
 
For top strap and bottom st rap (webbing) attach ment strength test, see Figure A .1. 
 
Figure A .1 — Top strap and bottom strap (webbing) attachment strength test  
  
 
viii © KEBS 2023  – All rights reserved  
 A 3 Joint strength of strap assembly  
 
A 3.1 Fasten the Top strap and bottom strap (webbing) by means of the buckle provid ed with the bag 
strap assembly.  
 
A 3.2  Ensure that the length of the joint assembly is at least 30 cm and extract the test specimen by 
cutting from both ends of the strap assembly to facilitate the tensile test.  
 
A 3.3  Determine the joint strength of the  strap assembly as the tensile strength tested in accordance 
with KS ISO 13935 -1. 
 
For top  strap, bottom strap (webbing) and buckle assembly see  Figure A .2. 
 
 
 
Figure A .2 — Strap assembly joint strength test  
 
 
  
 
© KEBS 2023  – All rights reserved  ix 
  Annex B  
 
(normative)  
 
Determination of dimensions  
 
B.1  Determine the bag dimensions  
 
Determine the bag dimen sions shall be as specified in B .2, B.3.and  B.4 by use of a steel rule. Ensure  that 
the area to be measured is free from creases and folds  
 
For detai ls See Figures B.1  to B.3. 
 
B.2  Bag dimensions  
 
B.2.1 Height  
 
B.2.2  Top width  
 
B.2.3 Bottom width  
 
B.2.4 Back to Front  
 
B.2.5 Piping  
 
B.3  Face pocket  
 
B.3.1 Height  
 
B.3.2 Top width  
 
B.3.3 Bottom width  
 
B.4 Top handle  
 
B.4.1 Height  
 
B.4.2 Span  
 
B.5 Straps, webbings and buckles  
 
B.5.1 Width  
 
B.5.2  Height  
   
x © KEBS 2023  – All rights reserved  
  
 
Figure B .1  Front view of back pack type of bag  
 
 
 
 
36 CM34 CM
27 CM25 CMH
H 1Top handle
2mm thick
Piping
Face pocket
Piping
FRONT VIEWA
BA1
B1 
© KEBS 2023  – All rights reserved  xi 
   
 
Figure B .2  Rear view of back pack type of bag  
 
 
Key to figures  B.1 and B .2 
 
A A1 B B1 H H1 
Bag Top 
width  Face Pocket 
top width  Bag Top 
width  Face Pocket 
Bottom width  Bag Height  Face Pocket 
Height  
 
 
 
 
 
xii © KEBS 2023  – All rights reserved  
  
 
 
 
 
 
Figure B .3 — Side view of back pack type of bag  
 
  
Pocket
zipPiping
SIDE  VIEWPiping
WebbingStrap
BuckleTop handle
2mm thick 
© KEBS 2023  – All rights reserved  xiii 
   
Annex C  
 
(normative)  
 
Determination of stitches per cm  
 
Count the number of stitches along a seam length of known distance in centimetres and determine the 
number of stitches per centimetre  
 
   
xiv © KEBS 2023  – All rights reserved  
 Annex D  
(normative)  
Drop test  
 
D1 Procedure  
 
A back pack type bag of specified dimensions (see Table F1) is loaded with relevant learning materials of 
mass as given in Table F1 collated with the size of bag. The loaded bag is dropped from the edge of a 
bench,1 -metre -high, to a flat floor. The drop te st is repeated 10 times. After the test, the tested bag is 
examined; the stitches and seams shall not open and the straps, webbings and buckles shall not give way 
or come off the stitched tacks  
 
Table F1 —  bag dimensions related to carrying capacity in kg   
 
 
Category of 
size 
  Dimensions of bag in cm   capacity in kg  
 Height  Top Width  Bottom Width  Back to Front  
1 28 18 23 8 2 
2 28-31 18-20 23-25 8-9 3 
3 31-37 20-24 25-28 9-11 5 
4 37-44 24-28 28-32 11-13 7 
5 44-55 28-34 32-36 13-15 10 
6 Above 55  Above 34  Above 36  Above 15  15