Reference number  
DRS 423: 2019  
© RSB 2019  
 
 
 RWANDA 
STANDARD  DRS 
423 
 
1st edition  
2019 -mm-dd 
Furniture — Chairs and tables for office 
furniture  — Functional sizes, strength and 
durability for seating and tables  
 
  DRS 423:2019  
©RSB 2019  - 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 2019  
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 reprodu ce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw   
ePortal: www.portal.rsb.gov.rw   DRS 423:2019  
iii                ©RSB 2019  - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and defi nitions  ................................ ................................ ................................ ..................  1 
4 Dimensions for office chairs and tables  ................................ ................................ ....................  3 
4.1 Methods for the determination of the dimensions  ................................ ................................ .. 11 
4.2 Dimensions for office chairs  ................................ ................................ ................................ ....... 3 
4.3 Dimensions for office tables  ................................ ................................ ................................ ....... 5 
5 Test methods for strength and durability of office furniture chairs and tables  ..................  11 
 DRS 423:2019  
©RSB 2019  - 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 423 was prepared by Technical Committee RSB/TC 54, Timber, furniture and engineered wood  
Committee membership  
The following organizations were represented on the Technical Committee on Timber, Furniture and Engineered 
wood  (RSB/TC 54) in the preparation of this standard.  
Action pour le Development de l`Artisanat au Rwanda (ADARWA)  
Association pour la défense des d roits des consommateurs au Rwanda  (ADECOR)  
Association pour la Promotion des Artisans du Bois  (APROAB)  
GiZ Eco—Emploi  
Integrated Polytechnic Regional Centre (IPRC) — KITABI  
Kalka and Partners Ltd  
MANUMETAL  
MASS DESIGN  
Ministry of Trade and Industry (MINICO M) 
National Industrial Research and development Agency (NIRDA)  
New Forest Company (NFC)  
REAL Contractors  
Rwanda Education Board (REB)  
Rwanda Environment Management Authority (REMA)  DRS 423:2019  
v                ©RSB 2019  - All rights reserved  
 Rwanda Public Procurement Authority (RPPA)  
Rwanda Water and Forestry Authority (RWFA)  
Rwanda Wood Association  
STRAW Tech  
University of Rwanda — College of Agriculture, Animal Science and Veterinary Medicine ( UR — CAVM)  
University of Rwanda — College of Science and Technology (UR — CST)  
Rwanda Standards Board (RSB) — Secretariat  DRS 423:2019  
©RSB 2019  - All rights reserved                  vi 
 Introduction   
Despite the Rwandan growth trend, the wood sector has not been implemented as required to produce high 
quality wood products and vigorous competitive market. The quality of wooden furniture is highly affected by 
the quality of ti mber, standardized production chain, quality control mechanism and grading rules. The lack of 
aforesaid factors results into market dominated by poor quality wooden furniture, compromised safety and unfair 
competition at the market.  
The emerging market dyn amics show that consumer’s preferences have gradually shifted from furniture made 
by local timbers to the imported ones, which  is considered as a limiting factor to the development and growth of 
the wood economy in Rwanda.  
To ensure a positive trade balanc e in wood market there is a dire need to improve and ensure quality of domestic 
wood products.  
This Standard is one of the series of standards on furniture in Rwanda. The series currently consists of the 
following:  
DRS 413:2019 Furniture — Quality and grading of wooden furniture ( Under development ) 
DRS 424:2019 Furniture — Specifications for bedsteads (Under development ) 
DRS 425:2019 Furniture — Storage units — Functional sizes, stability, strength and durability for storage units 
(Under development ) 
DRS 426:2019 Furniture — Chairs and tables for educational institutions — Functional sizes, strength, durability 
and stability  for seating and tables (Under development ) 
Furniture — Chairs and tables for home furniture — Functional sizes, strength, durabilit y and stability for seating 
and tables (Under development ) 
Furniture — Tables — Test methods for the determination of stability, strength and durability (Under 
development ) 
ISO 7170:2005 Furniture — Storage units — Determination of strength and durability  
ISO 7171:2019 Furniture — Storage units — Test methods for the determination of stability  
ISO 7173:1989 Furniture — Chairs and stools — Determination of strength and durability  
 DRS 423:2019  
1                ©RSB 2019  - All rights reserved  
 Furniture — Chairs and tables for office furniture — Functional sizes, 
strength and durability for seating and tables  
1 Scope   
This Rwanda standard specifies the basic functional sizes for office seating and tables. This document specifies 
methods for the determination of the dimension of office chairs and tables. This standard include s requirements 
for strength and durability . 
Requirement for materials, design , construction or quality  are not covered by this standard.  
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 e dition cited applies. For undated references, the 
latest edition of the referenced document (including any amendments) applies.  
ISO 24496 :2017 , Office furniture  - Office chairs  - Methods for the determination of dimensions  
ISO 21015 :2007, Office furniture  — Office work chairs — Test methods for the determination of stability, 
strength and durability.  
ISO 21016:2007, Office furniture — Tables and desks — Test methods for the determination of stability, strength 
and durability.  
DRS 426:2019, Furniture – Chairs and tables for educational institutions;  
DRS 425:2019, Furniture – Storage units – Functional sizes, stability, strength and durability for storage units  
3 Terms and definitions  
For the purposes of this standard, the terms and definitions in DRS 425 a nd DRS 426 and the following  apply.  
3.1 
Armrest  
Part of a chair that support s the arm  
3.2 
Adjustable  
Ability for the user to change the functions of the chair without the need of any tool   
©RSB 2019  - All rights reserved                  2 
 3.3 
Office chair  
Piece of seating furniture for one person, with a  backrest, with or without armrests and with our without headrest 
used for seating in an office environment . 
Note: The upper part of the chair, which includes the seat, can rotate in the horizontal plane and can be adjusted in height.  
Office chair fall into three types; type 1, type 2 and type 3.  
3.4  
Types of office chairs  
3.4.1 
Type 1 chair  
Adjustable work chair with large range of adjustment  
3.4.2 
Type 2 chair  
Adjustable work chair, some features may be fixed  
3.4.3 
Type 3 chair  
Work chair with limited adjustability  
3.5 
Work table/desk Type 1  
Work table/desk with height adjustable; the height can be changed by the user during use  
3.6 
Work table/desk Type 2  
Work table/desk with height selectable; the height can be adapted to the user at installati on 
3.7 
Work table/desk Type 3  
Work table/desk with fixed height  DRS 423:2019  
3                ©RSB 2019  - All rights reserved  
 3.8 
Work table/desk Type 4  
Work table/desk with limited height selectable or adjustable  
4 Dimensions for office chairs  and tables  
4.1 Dimensions for office chairs  
4.1.1  In the case of Figure 1 , the legroom shall be rectangular with dimensions as specified in Table 3.  
4.1.2  In the case Figure 2 , the legroom shall be curved with dimensions as specified in Table 3.  
NOTE  1 Figure 1 shows the legroom for all work surfaces which have straight front edges at least all along the width, W, 
see Table 3 . 
NOTE  2 Figure 2 shows the legroom for all work surfaces with non -straight front edges . 
4.1.2  The dimensions for office chairs are given in ISO 24496:2017, as listed in Table 1:  
Table 1 — Definition of dim ensions according to ISO 24496:2017  
No. Dimension description  ISO 24496:2017, clause reference  
1 Lumbar support height 
Adjustable height of lumbar 
support / Fixed height of 
lumbar support  3.16 add extra info on the 
mentioned clauses  
2 Angle between seat and back  3.1 
3 Seat inclination Seat pad 
angle adjustable / Seat pad 
angle fixed minimum  3.25 
4 Seat height, min.  3.23 
5 Adjustable depth of the seat 
/Fixed depth of the seat  3.22 
6 Backrest height  3.11 
7 Maximum distance from the 
backrest to the front of the 
armrests  3.6 
8 Height of armrests adjustable 
/ Height of armrests not 
adjustable  3.3  
©RSB 2019  - All rights reserved                  4 
 9 Height of adjustable neck rest 
or head rest /   Height of fixed 
neck rest or head rest  3.21 
10 Seat pad width  3.27, 3.28  
11 Seat pad depth  3.26 
12 Backrest width  3.10 
13 Radius of backrest - 
horizontal  3.13 
14 Armrest length  3.4 
15 Armrest width  3.7 
16 Minimum clearance between 
armrest assembly when 
armrest are in widest position  3.15 
17 Adjustable clear distance 
between armrest pads / Fixed 
clear distance between 
armrest pads  3.5 
18 Offset of the underframe  3.29 
Table 2: Dimensions of an office chair  (Dimensions in millimetres)  
No Dimension  Type 1 chair  Type 2 Chair  Type 3 Chair  
    Minimum  Maximum  Minimum  Maximum  Minimum  Maximum  
1 Seat height  400 520 420 510 430 480 
2 Adjustable depth of 
the seat  425 475 425 445 425 - 
3 Fixed depth of the 
seat Type 1 chair shall be 
adjustable  425 485 425 - 
4 Adjustable height of 
lumbar support  200 300 
180 300 190 - 
5 Fixed height of lumbar 
support  Type 1 chair shall be 
adjustable  180 300 180 - 
6 Maximum distance 
from the backrest to 
the front of the 
armrests   250 
 300 - 300 
7 Angle between seat 
and back  90 - 90 - 90 - 
8 Seat pad angle 
adjustable  -7 3 -7 -2 -7 -2 
9 
Seat pad angle fixed  Type 1 chair shall be 
adjustable  -5 3 -5 3 DRS 423:2019  
5                ©RSB 2019  - All rights reserved  
 10 Hip breadth clearance 
when armrest are in 
widest position  480 - 
460 - 460 - 
11 Adjustable clear 
distance between 
armrest pads  360 510 
460 510 460 - 
12 Fixed clear distance 
between armrest pads  Type 1 chair shall be  
adjustable  460 510 460 250 
13 Height of armrests 
adjustable  200 290 225 250 200 - 
14 Height of armrests not 
adjustable  Type 1 chair shall be 
adjustable  225 275 200 - 
15 Seat pad width  400 - 400 - 400 - 
16 Seat pad depth  425 - 425 - 400 - 
17 Backrest height  360 - 360 - 360 - 
18 Backrest width  360 - 360 - 360 - 
19 Radius of backrest  400 - 400 - 400 - 
20 Height of adjustable 
neck rest or head rest  550 740 590 - 590 - 
21 Height of fixed neck 
rest or head rest  Type 1 chair shall be 
adjustable  590 - 590 - 
22 Armrest length  150 - 150 - 150 - 
23 Armrest width  50  40  40  
24 Offset of the 
underframe  - 415 - 415 - 415 
4.2 Dimensions for office tables  
Office tables shall meet dimensions specified  in table 3.  
Table 3: Dimensions for office tables ( Dimensions in millimeters ) 
Dimensions  Work table/desk type  
Type 1  Type 2  Type 3  Type 4  
Fully 
adjustable  Fully 
selectable  Fixed 
height  Limited 
adjustable or 
limited 
selectable e 
h1 Height of 
the work 
surface  Sitting only  Minimum range 
650 -850 Minimum range 
650 -850 a 740 + 20 Min Max 
680 760 
Standing 
only Minimum range 
950 -1250  Minimum range 
950 -1250 a 1050 +20 Min Max 
1000  1180   
©RSB 2019  - All rights reserved                  6 
 Sit/stand  Minimum range 
650 -1250  N/a N/a Minimum range 
680 -1180  
t1 and 
t2 Maximum 
desk top 
thickness 
see figure 
1 At the front, 
t1 55 b 55 b 70 
70 
At 500 mm 
from the 
front edge, 
t2 80 b 90 b 100 
100 
k1 
(See 
Figure 
3) Minimum 
height of 
knee 
clearance 
for 
standing 
position 
only Applies only 
to tables with 
a height 
more than 
850 mm  700 d 700 d 700 d 700 d 
k2 Minimum 
depth of 
knee 
clearance 
for 
standing 
position 
only    80 80 80 80 
k3 
(see 
figure 
3) Minimum 
depth of 
foot 
clearance 
for 
standing 
position 
only    150 150 150 150 
f1 and 
f2 Minimum 
height of 
minimum 
foot 
clearance  Sitting only 
and sit/stand 
From 600 
mm to 800 
mm from the 
front edge, 
f1  120 120 120 120 
Standing 
only From 
front  edge 
to 150  mm, 
f2 120 120 120 120 
g1 Minimum 
legroom 
depth c  Sitting only 
and sit/stand  800 800 800 f 800 DRS 423:2019  
7                ©RSB 2019  - All rights reserved  
 D Minimum 
desk top 
depth g  800 800 800 f 800 
W Minimum 
legroom 
width  Sitting only 
and sit/stand  1200  1000  850 850 
Standing 
only 790 790 790 790 
a  Maximum increment of 20 mm  
b  Only applies to sitting and sit/stand work tables/desks  
c  The construction of the product shall ensure the minimum legroom depth                                                                                                                              
d  Measured from the floor  
e  The minimum and maximum valu es shall be obtained  
f  600 mm can in some situations be acceptable, e.g. when 17" or smaller flat screens are used, 
providing that the work surface is not against the wall and that two people are not sitting one in front of 
each other. Information about t hese limitations shall be provided with the product  
g  The dimension D is measured as the smallest dimension at the work area  
  
 
©RSB 2019  - All rights reserved                  8 
  
Key 
h1 height to the top of the work surface  
t1 maximum desk top thickness at the front  
t2 maximum desk top thickness at 500 mm from the front edge  
f1 height of foot clearance  
g1 minimum legroom depth  
w minimum legroom width  
 Figure 1 — Legroom and height for work tables/desks with straight front edges  
DRS 423:2019  
9                ©RSB 2019  - All rights reserved  
  
Key 
h1 height to the top of the work surface  
t1 maximum desk top thickness at the front  
t2 maximum desk top thickness at 500 mm from the front edge  
f1 height of foot clearance  
g1 minimum legroom dept  
w minimum legroom width  
Figure 2 — Legroom and height for work tables/desks with non -straight front edges  
 
©RSB 2019  - All rights reserved                  10 
  
Key 
1 front edge  
2 top of the work surface  
3 floor  
h1 height to the top of the work surface  
k1 height of knee clearance  
k2 depth of knee clearance  
k3 depth of foot clearance  
f2 height of foot clearance  
w minimum legroom width  
Figure 3 — Foot and knee clearance dimensi ons for standing position only  
DRS 423:2019  
11                ©RSB 2019  - All rights reserved  
 Measurement procedure  
5 Test methods  
5.1 Determination of  dimensions  
5.1.1  Position the work table/desk on a flat horizontal and rigid floor surface, with levelling device(s) fully 
closed. Inclinable desk top work surfaces shall be  set to the horizontal or as near to the horizontal as possible. 
Before commencing measurement procedure, it shall be determined whether the table/desk is for sitting, 
standing or sit/stand use.  
5.1.2  The minimum and maximum height of work surface shall be  measured at the front edge (see Figure 1) 
and the adjustment range shall be recorded. For height selectable work tables/desks type 2 and 4 the minimum 
height increments shall also be recorded.  
5.1.3  The legroom depth shall be measured at the working posit ion and with the rear edge of the work 
table/desk placed against a vertical wall.  
5.2 Test methods for strength and durability  of office furniture chairs and tables  
5.2.1 Strength and durability test s for office furniture chair  shall be performed in accordance with ISO 21015  
5.2.2 Strength and durability test s for office furniture tables shall be performed in accordance with ISO 21016  
 
  
©RSB 2019  - All rights reserved                  12 
 Bibliography  
[1] IS 4415, Glossary of terms relating to wooden furniture and fixture, 1974  
[2] Furniture testing 101, The Definitive Guide to No rth American Furniture Testing.  
Source: http://www.intertek.com/furniture  . 
[3] IS 3663 : 1991, Dimensions of chairs and tables for office purposes  
[4] EN 527 -1:2011 -08, Office furniture –Work tables and desks – Part 1: Dimensions  
 DRS 423:2019  
ICS 97.140 
 
 
©RSB 2019  - All right s reserved