Reference number  
DRS 356: 2017  
 
© RSB 2017  
 
 RWANDA 
STANDARD  DRS 
356 
 
First edition  
2017 -mm-dd 
 
Socks — Specification  
  DRS 356: 2017  
©RSB 2017  All rights reserved                  ii 
 
 In order to match with technological development and to keep continuous progress in industries, 
Standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
 
 
© RSB 2017  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce this document should be addressed to  
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 252 586103/582945  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  DRS 356: 2017  
iii                 ©RSB2017  All rights reserved  
 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
Introduction  ................................ ................................ ................................ ................................ ................  v 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  1 
4 Requirements  ................................ ................................ ................................ ................................  2 
4.1 General requirements  ................................ ................................ ................................ ..................  2 
4.1.1  Types  ................................ ................................ ................................ ................................ .............  2 
4.1.2  Materials  ................................ ................................ ................................ ................................ ........  2 
4.2 Specific r equirements  ................................ ................................ ................................ ..................  3 
4.3 Size................................ ................................ ................................ ................................ .................  4 
5 Marking  ................................ ................................ ................................ ................................ ..........  4 
6 Packing  ................................ ................................ ................................ ................................ ..........  5 
Annex  A (normative)  measurement of socks for size determination  ................................ .................  6 
A.1 Condit ioning of socks  ................................ ................................ ................................ ..................  6 
A.2 Sample sock preparation  ................................ ................................ ................................ .............  6 
A.3 Measurements  ................................ ................................ ................................ ..............................  6 
Bibliography  ................................ ................................ ................................ ................................ ...............  7 
 DRS 356: 2017  
©RSB 2017  All rights reserved                  iv 
 
 Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards adop ted 
by Technical committ ees are ratified by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
DRS 356 was prepared by Technical Committee RSB/TC 029, Textiles and Leather  Engineering , In the 
preparation of this standard,  reference was made to the following standard s: 
1) S.L.S. 400: 1976 Specification for nylon stretch socks.  
2) IS: 5084 -1969 Specification for nylon socks.  
3) SI 839 -1972 Men’s socks of polyamide stretch yarn.  
4) KS 08 -583: 1984 Specification for socks  
The assistance d erived from the above source s is hereby acknowledged with thanks.  
Committee membership  
The following organizations were represented on the Technical Committee on Textiles and Leather  Engineering  
(RSB/TC 029) in the preparation of this standard.  
C&H  
Consumer Association (ADECOR)  
National Agricultural Export Board (NAEB)  
National Industrial Research Institute (NIRDA)  
Rwanda Development Board  (RDB)  
University of Rwanda - College of Science and Technology ( UR-CST)  
UTEXRWA  
Rwanda  Standards Board  (RSB) – Secretariat  
  DRS 356: 2017  
v                 ©RSB2017  All rights reserved  
 
 Introduction  
At present, a variety of socks sizes are being imported and manufactured locally from a number of textile fibres 
mainly nylon, polyester, wool, acrylic, cotton and their blends. This standard is intended to streamline the socks 
sizes into uniform dimensions and stipulate the quality requirements of materials used in manufacturing socks.  
 DRS 356: 2017  
1                 ©RSB2017  All rights reserved  
 
 Socks —Specification  
1 Scope  
This Draft Rwanda Standard specifies the requirements , methods of test and sampling  for seamless  socks 
knitted in plain, rib or fancy stitches.  
This Draft Rwanda Standard applies to seamless socks manufactured from nylon, polyes ter, wool, acrylic, 
cotton and/or their various blends . 
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 139, Textiles Standard atmospheres for conditioning and testing  
ISO 2060, Textiles  — Yarn from packages  — Determination of linear density (mass per unit length)  — Skein 
method.  
ISO 2062 , Textiles  — Yarn from packages  — Method for determination of breaking toad and elongation at the 
breaking toad of single strands (CRL, CRE and CRT testers).  
ISO 6939 , Textiles  — Yarns from packages  — Method of test for breaking strength of yarn by th e skein method  
ISO 105 -C06, Textiles — Tests for colour fastness -- Part C06: Colour fastness to domestic and commercial 
laundering 
ISO 105 -E04, Textiles — Tests for colour fastness -- Part E04: Colour fastness to perspiration 
ISO 105 -X12, Textiles — Tests for colour fastness -- Part X12: Colour fastness to rubbing  
RS ISO 105 -B01, Textiles — Tests for colour fastness -- Part B01: Colour fastness to light: Daylight  
RS ISO 105 -B02, Textiles — Tests for colour fastness -- Part B02: Colour fastness to art ificial light: Xenon arc 
fading lamp test . 
ISO 105 -N02, Textiles — Tests for colour fastness -- Part N02: Colour fastness to bleaching: Peroxide  
3 Terms  and definitions  
For the purposes of this standard, the follow ing terms and definitions apply  
3.1  
foot length  
distance from the tip of the toe to the apex of the heel, that is the distance between C and 0 (Figure 1).  
3.2  
leg length  
distance from the top of the socks to the apex of the heel, that is, the distance between A and 0 (Figure 1).   
©RSB 2017  All rights reserved                  2 
 
 3.3 
batch of soc ks 
batch of socks shall mean more than one pair of socks of the same type and size packed together.  
3.4 
tenacity  
ratio of the breaking strength to the linear density of the unstrained specimen, usually expressed in centinewtons 
per tex . 
4 Requirements  
4.1 Genera l requirements  
4.1.1  Types  
Depending upon the pattern of stitches, socks shall be of any one of the following three types:  
a) plain -knitted ; 
b) rib-knitted ; or 
c) fancy -knitted . 
4.1.2  Materials  
4.1.2.1  Non Elastic Yarn  
4.2.1.1  The yarn used in knitting,  linking and splicing the socks shall conform to the requirements of Table 
1 
property  YARN TYPE  METHOD OF 
TEST  Nylon ( 6 and 
6.6) Polyester  Wool Acrylic  Cotton  
 
Minimum Tenacity 
g/tex (breaking 
strength/Linear 
density)  35.0 35.0 35.0 35.0 35.0 ISO 6939  
ISO 2060  
Elongation at 
break  30.0 30.0 30.0 30.0 30.0 ISO 2062  
 
4.2.1.2  The minimum tenacity (g/tex) and elongation at break (per cent) of each yarn used to make yarn to 
yarn blended socks, shall be as  shown against each yarn type in Table 1  
4.2.1.3  The ratings of minimum tenacity (g/tex) and elongation at break (per cent) of the fibre bl ended yarn 
used in the blended socks, shall be not less than those of the fibre component in the blend whose yarn has a 
lower rating in accordance with Table 1 i.e. in a nylon/wool or polyester/wool  blend; the minimum tenacity and 
elongation at break of  the yarn shall be not  less than that of the woollen yarn as shown in Table 1.  DRS 356: 2017  
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 4.1.2.2  Elastic Yarn  
The elongation of elastic yarn or covered rubber thread used for laying in the top portion of finished socks shall 
be not less than 450 per cent , when determined using ISO 2062 . 
 
 
 
Key 
Foot Length — Distance from C to O  
Leg Length — Distance from A to O  
Figure 1 — Sock  
4.2 Specific requirements  
4.2.1 The socks shall be knitted on circular machines.  The top of the socks shall be knitted in rib or plain 
stitches with covered rubber thread or any other suitable elastic yarn laid in; and the leg and instep shall be 
knitted in plain, rib or fancy stitches depending on the type of socks.  
4.2.2 The top portion of socks with covered rubber thread or any other suitable elastic yarn shall be not less 
than 25 mm.  
4.2.3 In case the covered rubber thread or any other suitable elastic yarn is not used at the top of the socks, 
the top portion shall be knitted in a rib of not less than 80 mm and  it shall be extended proportionally according 
to socks sizes.  
4.2.4 The heel and toe portions of the socks s hall be knitted in plain stitches with splicing.  The splicing shall 
be uniform throughout and spliced portions free from creases and/or folds.  
4.2.5 The socks shall be securely joined at the toe. The joining shall be elastic, smooth and free from knots. 
It shall not give way when the socks are stretched to the full extent of the stretchability of the socks . 
4.2.6 The socks shall be free from manufacturing defects, such as mends, ladders, improper splicing and 
both dyeing and finishing defects.   
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 4.2.7 The dy ed socks shall conform to colour fastness requirements as given in Table 2.  
Table 2 — Colour fastness requirements  
S/N Colour fastness  Numerical rating  Method of test  
(i) Washing (change in colour and 
staining)  ≤4  ISO 105 -C06 
(ii) Perspiration (acid and  alkali)  ≤3  ISO 105 -E04† 
(iii) Rubbing (staining dry and wet)  
 ≤4  ISO 105 -X12 
(iv) Light  ≤5  RS ISO 105 -B01 
(v) Peroxide Washing  ≤4  RS ISO 105 -N02 
4.3 Size 
4.3.1 The socks shall be grouped into five different sizes namely:  
a) Small; 
b) Medium ; 
c) Large; 
d) Extra Large ; and  
e) Free 
4.3.2 The size of socks shall be determined by both foot length and leg length dimensions given in Table 3.  
Table 3 — Size dimensions  
S/N Socks size  Foot length  
in mm Leg length  
in mm Method of test  
(i) Small  100-125 120-145 Annex A  
 (ii) Medium  130-155 150-175 
(iii) Large  160-185 180-205 
(iv) Extra Large  190-215 210-225 
(v) Free Above 220  Above 230  
4.4.3 The free size shall be grouped further and designated numerical sizes whose size dimensions shall not 
be less than those specified in Table 3, (v). The dimensions of subsequent sizes shall be at intervals of at least 
30 m m. 
4.4.4 In every size as given in Table 3, there shall be an increase of not less than 20 % in the foot length and 
leg length dimensions of 100 % cotton so cks and blended socks in which cotton is in higher proportion.  
5 Marking  
5.1 One sock in each pair of socks shall be marked with the following information; except (iv) and (v) of which 
if not marked on the sock, shall be displayed as specified in 5.2 : DRS 356: 2017  
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 a) name /trade mark of the manufacturer;  
b) fibre composition;  
c) size; 
d) care instructions  
e) country of origin.  
5.2 (d and ( e) of 5.1shall be clearly displayed on each pair of socks.  
6 Packing  
6.1 Each pair of socks shall be folded properly at the heel gore line so as to form two layers.  Each folded 
pair shall be wrapped or placed in an appropriate  bag or cardboard box of suitable size.  
6.2 A batch of pairs of socks or several batches shall be plac ed in a packing material of suitable size which 
shall be secured properly.  
6.3 Each package containing a batch of socks or several batches shall have the following information which 
shall be legibly and indelibly indicated on the package, the swing ticket and/or accompanying documents:  
a) name /trade mark  and address  of manufacture;  
b) number of pairs in each batch;  
c) total number of batches in the package;  
d) (iv) fibre composition  
e) country of origin   
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 Annex  A 
(normative)  
 
measurement of socks for size determination  
A.1 Conditionin g of socks  
Before foot length and/or leg length dimensions are taken, the socks shall be conditioned in accordance with 
ISO 139 Take the measurements in an atmosphere similar to that used for conditioning.  
A.2 Sample  sock preparation  
Take the conditioned sampl e sock to be measured.  Lay it flat on a smooth table.  Remove by hand all creases 
and wrinkles without stretching the sock.  
A.3 Measurements  
A3.1  Take the dimensions of both the foot length and leg length as defined in 3.1, 3.2 and Figure 1, both 
measurements  to be taken correct to the nearest 5 mm.  
A3.2  The pair shall be in conformity with the requirements of Table 3 if none of the values as determined in 3.1 
varies from the specified value by more than the specified tolerance.  
  DRS 356: 2017  
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 Bibliography  
[1] ISO/IEC Directives, Part  2, Rules for the structure and drafting of International Standards , 2016  DRS 356: 2017  
ICS 59.060.01  
 
 
©RSB2017  All right s reserved