Reference number  
DRS 375: 2017  
© RBS yyyy 
© RSB 2017  
 
 RWANDA 
STANDARD  DRS 
375 
 
First edition  
2017 -mm-dd 
 
Gents ’ briefs  — Specification  
  DRS 375: 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 specifie d, 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 b e addressed to  
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
Tel. +250 252 586103/ 582945  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  DRS 375: 2017  
iii                 ©RSB 2017 All rights reserved  
 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4. Req uirements  ................................ ................................ ................................ ....Error! Bookmark not defined. 1 
4.1 General Requirements  ................................ ................................ ................................ ...............................  21 
4.2 Dimensions  ................................ ................................ ................................ ................................ .................  21 
4.3.1  Fabrics  ................................ ................................ ................................ ................................ ....................  2 
4.3.2  Sewing Thr eads  ................................ ................................ ................................ ................................ ..... 2 
4.3.3  Elastic Strap  ................................ ................................ ................................ ................................ .........  32 
4.4 Seams and Stitches  ................................ ................................ ................................ ...............................  3 
4.5 Sp ecific requirements  ................................ ................................ ................................ ................................ .. 3 
5. PACKING  ................................ ................................ ................................ ................................ ..............  43 
6. MARKING  ................................ ................................ ................................ .Error! Bookmark not defined. 3 
7. Sampling and Co mpliance  ................................ ................................ ................................ ............................  4 
7.1 Sampling  ................................ ................................ ................................ ................................ .......................  4 
7.2 Compliance  ................................ ................................ ................................ ................................ ...................  4 
Annex  A (normative)  METHODS OF TEST  ................................ ................................ ................................ .... 65 
 DRS 375: 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 
adopted by Technical committ ees are ratifie d by me mbers of RSB Board of Director s for publication and 
gazettment as Rwanda Standards.  
DRS 375 was prepared by Technical Committee RSB/TC 029, Textiles and Leather ,  
In the preparation of this standard, reference was made to the following standard s: 
1) IS 4046 -1977:  Specification for gent’s cotton knitted briefs  
2) KS 495:1983 Specification for gent’s knitted briefs  
The assistance de rived 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 (RSB/TC 
029) in the preparation of this standard.  
Participants  
Rwanda  Standards Board  (RSB) – Secretariat  DRS 375: 2017  
v                 ©RSB 2017 All rights reserved  
 
 Introduction  
A number of hosiery manufacturers are en gaged in fabricating gent’s briefs from the knitted fabrics 
manufactured elsewhere.  This standard is intended to help the manufacturers , importers and regulators  in 
ensuring quality goods and safeguarding the interests of the consumers.  
 DRS 375: 2017  
1                 ©RSB 2017 All rights reserved  
 
 Gents ’ briefs — Specification  
1 Scope  
This draft Standard prescribes the requirements , sampling Test methods  and acceptance criteria  for gent’s 
briefs. It applies to all types of knitted briefs for men and boys.  
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 do cument.  For dated references, only the edition  cited applies. For undated references, 
the latest edition of the referenced document (including any amendments) applies.  
ISO 3071  Textiles  — Determination of pH of aqueous extract  
BIS IS 1383  Methods for Determination of Scouring Loss In Grey And Finished Cotton Textile Materials  
ISO 105-B01 Textiles  — Tests for colour fastness  — Part B01: Colour fastness to light: Daylight  
ISO 11641  Leather  — Tests for colour fastness  — Colour fastness to perspiration  
ISO 105-C10 Textiles  — Tests for colour fastness  — Part C10: Colour fastness to washing with soap or soap 
and soda  
ISO 105 -X12 Textiles — Tests for colour fastness — Part X12: Colour fastness to rubbing  
3 Terms and definitions  
For the purposes of this standard,  the terms and definitions apply.  
3.1  
briefs  
tight fitting underwear without leg portion  
3.2 
lot 
all the briefs of same size and manufactured from plain knitted fabric of same count of yarn, knitted on 
machine of same gauge and delivered to a buyer against one despatch note   
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 4 Requirements  
4.1 General Requirements  
The briefs shall be free from any manufacturing defects, such as mends, ladders, dropped stitches, holes, 
cuts, missed stitches at the stitched portions and stains.  All the accessories of the  briefs shall be as durable 
as the briefs themselves.  
4.2 Dimensions  
The dimensions of briefs when measured by the method prescribed in A1 shall comply with the requirements 
given in Table 1  
Table 1- Dimensions  of gent’s briefs  
S/N SIZE  Width across waist  
 (cm)  Width across seat  
(HIP)  
(cm)  
i.  70 26 35.0 
ii.  75 28 37.5 
iii.  80 30 40.0 
iv.  85 32 42.5 
v.  90 35 45.0 
vi.  95 38 47.5 
vii.  100 41 50.0 
viii.  105 44 52.5 
ix.  110 47 55.0 
x.  Tolerance  ± 2.0  ± 1.5  
NOTE  1. Size of the brief is denoted by a number which is the hip (seat) measurement of the brief in centimetres.  
NOTE 2 The width across waist of the briefs with elastic strap shall be varied depending upon the elasticity of the 
waist strap.  
4.3 Raw Materials  
4.3.1  Fabrics  
The fabrics of which the briefs are made shall comply wit h the requirements of the relevant Rwanda Standard  
on knitted fabrics.  
4.3.2  Sewing Threads  
The sewing threads used shall comply with relevant specification of the sewing thread used.  DRS 375: 2017  
3                 ©RSB 2017 All rights reserved  
 
 4.3.3  Elastic Strap  
4.3.3.1  In case of briefs with elastic straps, the briefs shall be supplied with the elastic strap, woven, knitted 
or non -woven having a minimum width of 20 mm at the waist of the briefs.  
4.3.3.2  The elastic strap shall be stitched to the waist band by lock stitches in case of woven straps and by 
flat or o ver-lock stitches in case of knitted strap.  Alternatively, the knitted fabric shall be folded and stitched at 
the waist band to accommodate the elastic strap.  
4.3.3.3  Elastic strap having a width of not less than 12 mm shall be inserted at the thigh openi ng for 
providing a better fit.  
4.3.3.4  The elastic flat braid used shall comply with the requirements of the fabric used.  
4.4 Seams and Stitches  
4.4.1  The seams shall be straight and continuous.  The seams shall fit the type of fabric.  
4.4.2  All the seams connecting the various parts of the briefs shall be reinforced to cover all the raw edges.  
4.5 Specific  requirements  
The briefs shall comply with the quality requirements specified in table 2.  
Table 2  - Specific requirements for Briefs  
Characteristics  Require ment  Method  of Test  
Dimensional change due to relaxation 
(both direction), percent, Mar  5  Annex A  
Scouring loss percent, Max  2 BIS IS 1383:  
pH value of aqueous extract  6 to 8  ISO 3071:  
Colour fastness of dyed briefs to:  
a) Light (see Note)  ≥4  ISO 105-B01 
b) Washing test:  
Change in colour  
Staining on adjacent fabric   
≥3  ISO 105-C10:  
c) Perspiration  
Change in colour  
Staining on adjacent fabric   
≥4  
 ISO 11641:  
d) Rubbing (wet and dry)  ≥4  ISO 105 -X12: 
  
©RSB 2017   All rights reserved                  4 
 
 5 Packing  
The briefs shall be  packed in a suitable package  protecting them from dust, dirt and water.  
6 Labelling  
Each brief shall bear a label, sewn on the inside of the brief on which the following particulars shall be clearly 
and durably be marked:  
a) Manufacturer’s name or trade mark;  
b) Size;  
c) Care instructions ;   
d) Fibre composition ; 
e) Country of Origin  
7 Sampling  and Acceptance criteria  
7.1 Sampling  
Sampling shall be done in accordance with Table 3.  
Table 3 -Sample Size and Permissible Number of Non -Conforming Briefs  
Number of Briefs in the 
Lot Physical characteristics  Other requirements,  
 
 
Number of Briefs to be 
Inspected  Number of Briefs’ to be 
Inspected  Permissible Number of 
Non-Conforming Briefs  
Up to 300 10  0 3 
301 to 500  20  1 5  
501 to 1000  32  3 5  
1001 and above   50  5 8 
  
 DRS 375: 2017  
5                 ©RSB 2017 All rights reserved  
 
 7.2 Acceptance  criteria  
The number of briefs to be tested and criterion for conformity for each of the characteristics shall be as 
follows:   
Characteristic  Number of Drawers to be Tested  Criterion for Conformity  
Freedom from defects, wales and 
courses and dimensions  See co1 2 of Table 3 Non-conforming briefs not t o exceed 
the corresponding num ber given in 
co1 3 of Table 3 
Dimensional change, scouring Ioss , 
pH value of aqueous extract  See co1 4 of Table  3 All the briefs to satisfy the relevant 
requireme nts 
Colours fastness  1 each of the same colour shade and 
for lot size up to 500 and 2 above 
500. All the test specimens to satisfy the 
relevant requirements  
 
  
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 Annex  A 
(normative)  
 
Methods of test  for dimensions  
A.1 Conditioning of test .specimens and atmospheric conditions for testing  
The test specimens shall be tested in prevailing  atmospheric conditions. In case of dispute, the  samples shall 
be conditioned and tested in the  standard atmosphere as given in ISO …   
A.2 Dimensions  
A.2.1  Procedure  
Take each garment constituting the test sample. Lay it flat on a table. Remove by hand all creases and 
wrinkles without distorting it. Measure to the nearest 0.5 cm the dimensions given.  
A.3 Dimensional changes due to relaxation  
A.3.1  Marking of Test Specimens  
A.3.1.1  Take a brief from the test sample. Cut from it a test specimen measuring approximately 20 cm x 
20 cm in such a way that the two of its sides are parallel in the direction of wales and the other two parallel in 
the direction of courses. Mark the direction o f wales and courses in the test specimen.  
A.3.1.2  Mark centrally on the test specimen by means of indelible ink or a fast dyed cotton sewing thread 
an area 10 cm x 10 cm with two of its sides in the direction of wales and the other two in the direction of  
courses. Spread this test specimen on a flat smooth surface. Carefully remove by hand all creases and 
wrinkles. Within this area, mark six pairs of marks, three pairs each in the wales direction and the courses 
direction in such way that the distance betw een each pair of marks is the same.  
A.3.2  Procedure  
A.3.2. 1 Place test specimen on a glass plate and carefully remove by hand all creases and wrinkles without 
distorting it and place the other glass plate on the test specimen. Measure, correct to the nearest mi llimetre, 
the distance between each pair of marks separately.  
A.3.2. 2 Lay the test specimen flat in a tray of suitable size and of depth minimum 10 cm. Soak it under a 
head of 25 mm of water containing 0.5 percent suitable wetting agent at room temperatur e for 2 hours. Drain 
out the water and remove the test specimen carefully so that it is not stretched and lay it flat on a smooth 
surface. Remove the excess of water by an absorbent material and dry it at room temperature.  
A.3.2. 3 After drying condition th e test specimen to moisture equilibrium at room temperature. Place it on the 
glass plate. Carefully remove all wrinkles and creases and place the other glass plate on the test specimen. 
Measure, correct to the nearest millimetre, the distance between each pair of marks separately.  DRS 375: 2017  
7                 ©RSB 2017 All rights reserved  
 
 A.3.3  Calculation  
A.3.3. 1 Calculate separately the percentage of dimensional change both in the direction of wales and in 
the direction of courses by the following formula:  
S = 100 x (a - b)/ a  
where  
S = dimensional change, percent ;  
a = the distance between a pair of marks (along the wales or courses as the case may be) before soaking; 
and b = the distance between the same pair of marks after soaking.  
A.3.3.2 Calculate separately the dimensional change between all the three pairs of marks in the direction 
of wales and in the direction of courses and calculate the average dimensional change in each direction.  
 
 DRS 375: 2017  
ICS 59.080.30  
 
©RSB 2017  All rights reserved