Reference number  
DRS 413:2019  
© RSB 2019  
 
 
 RWANDA 
STANDARD  DRS 
413 
 
1st edition  
2019 -nn-dd 
Furniture — Quality and grading of 
wooden furniture   
  DRS 413:2019  
ii                ©RSB 2019  - All rights reserved  
 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. 
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Rwanda Standards  Board  
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KK 15 Rd, 49  
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Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rs b.gov.rw   
ePortal: www.portal.rsb.gov.rw   DRS 413:2019  
iii                ©RSB 2019  - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and defi nitions  ................................ ................................ ................................ ..................  1 
4 Categories of wooden furniture  ................................ ................................ ................................ .. 2 
5 Requirements for quality of wooden furniture  ................................ ................................ ..........  2 
5.1 Timber species  ................................ ................................ ................................ .............................  2 
5.2 Moisture Content  ................................ ................................ ................................ ..........................  3 
5.3 Measurement  ................................ ................................ ................................ ................................  3 
5.4 Tolerance  ................................ ................................ ................................ ................................ ....... 3 
5.5 Quantity  ................................ ................................ ................................ ................................ .........  3 
5.6 Dimensions  ................................ ................................ ................................ ................................ ... 4 
5.7 Finishing  ................................ ................................ ................................ ................................ ........  4 
6 Grading of wooden furniture  ................................ ................................ ................................ ....... 4 
6.1 Grade I  ................................ ................................ ................................ ................................ ...........  4 
6.2 Grade II  ................................ ................................ ................................ ................................ ..........  4 
6.3 Grade III  ................................ ................................ ................................ ................................ .........  4 
7 Packaging  ................................ ................................ ................................ ................................ ...... 6 
8 Marking  ................................ ................................ ................................ ................................ ..........  7 
 DRS 413:2019  
iv                ©RSB 2019  - All rights reserved  
 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 413 was prepared by Technical Committee RSB/TC 54, Timber, furniture and engineered wood.  
In the preparation of this standard, reference was made to the following standard s: 
1) ISO 21887 - 2007 -11: Durability of wood and wood - based products — Use classes  
2) GS 983:2009, Furniture — Specification for Furniture Components   
The assistance de rived from the above source is hereby acknowledged with thanks.  
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 droits 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 P artners Ltd  
MANUMETAL  
MASS DESIGN  
Ministry of Trade and Industry (MINICOM)  
National Industrial Research and development Agency (NIRDA)  DRS 413:2019  
v                ©RSB 2019  - All rights reserved  
 New Forest Company (NFC)  
REAL Contractors  
Rwanda Education Board (REB)  
Rwanda Environment Management Authority (REMA)  
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 413:2019  
vi                ©RSB 2019  - All rights reserved  
 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 timber, standardized production chain, quality contr ol 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 dynamics 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 bal ance 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, durabil ity 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 durabilit y 
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 413:2019  
1                ©RSB 2019  - All rights reserved  
 Furniture — Quality and grading of wooden furniture  
1 Scope   
This Draft Rwanda Standard establishes  guidelines for classification and grading of furniture components for 
general  application in furniture and similar products.  This standard spells out the requirements for machined 
wood products intended for general application in furniture including  furniture for load bearing,  furniture for non -
load bearing and furniture for decora tive art . 
 
Though this standard is not intended for non -wooden furniture, it i s applicable to furniture  with wooden 
components.  
 
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.  
ISO 24294 :2013: Timber  - Round and sawn timber - Voca bulary  
RS EAS 24:2000:  Timber industry – Glossary of terms  
EAS 325: Wood preservative and treated timber – Guide to sampling and preparation of wood preservative and 
treated timber for analysis  
DRS xnn on Round and sawn timber - Nomenclature of timbers  (Under development)  
3 Terms and definitions  
For the purposes of this standard, the t erms and definitions given in ISO 24294, RS EAS 24:2000  and the 
following apply . 
3.1 
Furniture  
Movable and unmovable objects intended to support various activities such as seating, eating, sleeping , 
decorative art  and storage . 
EXAMPLE  Furnishing s, house fittings, fitments, accessories movable, fixtures, units, appliances, chattels and 
amenities ; objects that make a building  or a room suitable for living or working in.  
 DRS 413:2019  
2                ©RSB 2019  - All rights reserved  
 3.2 
Furniture q uality  
Degree to which a set of  characteristics of wooden furniture fulfil requirement s 
3.3  
Grading  
Category or rank given to different quality requirements for wooden furniture having the same functional use  
3.4 
Plugs  and fillers  
Inserts into a piece of lumber to improve its appearance and usefulness  
4 Categories  of wooden furniture  
4.1 Furniture for load bearing  
Wooden furniture capable  to support the weight of the overlying objects. Furniture for load bearing include  but 
not limited to  tables, chairs, beds, stair case , floor, cupboard, storage units  and cabinet . 
4.2 Non-load bearing  Furniture  
Wooden  furniture  not intended to support the weight of overlying object . Non load bearing furniture  include  but 
not limited to  skirting, architraves, soffit, furniture fittings , wall panelling and wood panels.  
4.3 Decorative furniture  
Load bearing or non – load bearing furniture desi gned to serve its purpose with ornament al features . 
5 Requirements for  quality of wooden furniture  
5.1 Timber species  
Timber for wooden furniture shall be species recognized as being resistant to microorganisms, insect and 
marine borers attack. Perishable timber species shall be accepted when such timber is treated against 
microorganisms, insect and marine borers with a n on-leachable preservative  complying with the requirements 
of EAS 325 . 
Timber  used for wooden furniture shall be one of the renown timbers species listed in DRS xnn (Under 
development) . However, this list does not exclude the use of other species of timber provided they are found 
suitable for any particular purpose.  
Note  Renown timber species for load bearing wooden furniture in Rwanda include Markhamia lutea,  Entendrophragma 
excelsum, K haya anthoteca,  Cedrela serrata , Entendrophragma utile, Entendrophragma cylindricum, Milicia excelsa, 
Eucalyptus spp  and Cupressus lustanica.  DRS 413:2019  
3                ©RSB 2019  - All rights reserved  
 5.2 Moisture Content  
The moisture content of the mach ined wood products shall be  
For all applications the moisture co ntent  shall be within the limits of 12  – 19%. 
Note  Specific percentage values for moisture content within the provided ranges maybe agreed between 
two parties.  
5.3 Measurement  
The thickness, width, diameter and length of furniture c omponents shall be determine d using calibrated/verified 
tools namely  micrometer screw gauge,  calliper or  tape measure  as ap propriate to an accuracy of at least 1 mm. 
5.4 Tolerance  
Tolerance on furniture components shall be as follows:  
Thickness: ± 1 mm 
Width: ± 1 mm 
Length: For furniture  components, a tolerance of 15 mm shall be allowed. For  multiple lengths, a tolerance of 
10 mm shall be allowed for every unit cut.  
5.5 Quantity  
The quantity of furniture components may be expressed in cubic meter (m3), square meter (m2), running meter 
(m) and  number of pieces where:  
Running meter (m) = Sum of length of all similar pieces (Length of one piece (m) x Total Number of pieces)  
Surface  area  (𝑚2)=𝑇𝑜𝑡𝑎𝑙  𝑙𝑒𝑛𝑔𝑡 ℎ (𝑚) x 𝑊𝑖𝑑𝑡 ℎ (𝑚𝑚 )
103              
𝑉𝑜𝑙𝑢𝑚𝑒  (𝑚3)=𝑁𝑢𝑚𝑏𝑒𝑟𝑜𝑓  𝑝𝑖𝑒𝑐𝑒𝑠  x𝑆𝑢𝑟𝑓𝑎𝑐𝑒  𝑎𝑟𝑒𝑎  𝑜𝑓 𝑜𝑛𝑒 𝑝𝑖𝑒𝑐𝑒  (𝑚2 )xThickness  (mm )
103 
𝑉𝑜𝑙𝑢𝑚𝑒  (𝑚3)=𝑅𝑢𝑛𝑛𝑖𝑛𝑔  𝑚𝑒𝑡𝑒𝑟  (𝑚)xWidth  (mm )
103x 𝑇ℎ𝑖𝑐𝑘𝑛𝑒𝑠𝑠  (𝑚𝑚 )
103 
𝑉𝑜𝑙𝑢𝑚𝑒  (𝑚3)=𝑁𝑢𝑚𝑏𝑒𝑟  𝑜𝑓 𝑝𝑖𝑒𝑐𝑒𝑠  xArea  of cross  sect ion per piece  (m𝑚2 )
106x Length  (m) DRS 413:2019  
4                ©RSB 2019  - All rights reserved  
 5.6 Dimensions  
Furniture components shall be manufactured in accordance with specifications in the working drawing as agreed 
between the purchaser and the manufacturer.  
5.7 Finishing  
Finishing of wooden furniture components shall  be by sanding and application of the coat surface finish.  
6 Grading of wooden furniture  
Furniture components meeting requirements in clause 5 are classified by appearance and defects inherent in 
the wood and manufacturing defects visible on the surface of t he product at the time of grading.  
According to appearance and defects, furniture components are classified into three main grades. These are 
grade I , grade II  and Grade III . 
6.1 Grade I  
This is the highest grade in which pieces of wooden furniture are clear and free of natural and machining defects 
as specified in Table 1. It is intended for applications where the original natural colour of the wood is required 
after finishing  
6.2  Grade II  
This is the medium grade required where less demanding applications than Grade I are desired . It includes 
pieces that can be repaired by plugging, filling and sanding and natural or machining characteristics that are 
acceptable for a fine appearance. Machined furniture components in this grade are intended for applications 
wher e they can be stained in finishing.  
6.3 Grade III  
This grade has many of the characteristics present in Grade II but is generally less restrictive in natural and 
machining characteristics. This grade is intended for low cost applications and will provide an acceptable 
product when it is painted with an opaque finish. Filling and sanding of characteristics are permitted. The product 
must however be able to perform for the use intended.  
Table 1: Permissible defects in furniture components  
No SEASONING  
DEFECTS  GRADE I  GRADE II  GRADE III  
1 
1.1 WARP     
1.1.1 Bow Not allowed  Not allowed  Not allowed  
1.1.2  Spring  Not allowed  Not allowed  Not allowed  
1.1.3  Cup Not allowed  Not allowed  Not allowed  DRS 413:2019  
5                ©RSB 2019  - All rights reserved  
 No SEASONING  
DEFECTS  GRADE I  GRADE II  GRADE III  
1 
1.1.4  Twist  Not allowed  Not allowed  Not allowed  
1.2 Check  Not allowed  Allowed.  
Maximum 0,25 mm 
wide, 10 mm long in 
max 5 % of parcel  Allowed.  
Maximum 0,25 mm 
wide, 10 mm long 
in max 10 % of 
parcel  
1.3 End splits  Not allowed  Not allowed  Not allowed  
1.4 Cracks  Not allowed  Not allowed   Not allowed  
2 BIOLOGICAL 
DEFECTS     
2.1 BORER DEFECTS     
2.1.1  Pin worm  Not allowed  Allowed.  
One for every 1, 0 m 
length, max 5% of 
parcel. Filled and 
plugged.  Allowed.  
Max 2 for every 1, 
0 m length. 
Scattered. Filled 
and plugged.  
2.1.2  Shot hole  Not allowed  Not allowed  Not allowed  
2.1.3  Grub holes  Not allowed  Not allowed  Not allowed  
2.2 NATURAL DEFECTS     
2.2.1  Resin pockets/Pitch 
pockets  Not allowed  Not allowed  Maximum 2 
allowed not 
exceeding 1,5 mm 
wide and 10 mm 
long. Max 10% of 
parcel  
2.2.2  Sound knots/Tight knots  Maximum 1 smooth 
knot allowed; 
diameter not more 
than 1/3 width in 
every 1,0 m length  Maximum 1 smooth 
knot allowed; diameter 
not more than 1/4 
width in every 1,0 m 
length  Maximum 1 smooth 
knot allowed; 
diameter not more 
than 1/3 width in 
every 1,0 m lengt h 
2.2.3  Pin knots  Not allowed  Not allowed  Not allowed  
2.2.4  Splay or Arris knots  Not allowed  Not allowed  Not allowed  
2.2.5  Unsound 
knots/Decayed knots  Not allowed  Not allowed  Not allowed  
2.2.6  Compression failure  Not allowed  Not allowed  Not allowed  
2.2.7  Bright sapwood  Not allowed  Not allowed  Not allowed  
2.2.8  Medium sapstain  Not allowed  Not allowed  Allowed.1/4 of max 
5% 
2.2.9  Bluestain  Not allowed  Not allowed  Allowed  
2.2.10  Discoloration  Not allowed  Not allowed  Allowed  DRS 413:2019  
6                ©RSB 2019  - All rights reserved  
 No SEASONING  
DEFECTS  GRADE I  GRADE II  GRADE III  
1 
2.2.11  Slope of grain  1:10 1:8 Irregular grain 
allowed  
3.0 MANUFACTURING 
DEFECTS     
3.1 Hit and miss  Not allowed  Allowed.  
0, 5 mm deep, 300 mm 
long. 10 % of parcel  Allowed.  
0, 5 mm deep, 300 
mm long. 10 % of 
parcel  
3.2 Chipped grain  Allowed.  
Maximum 0 , 5 mm 
deep. Max 10 % 
surface of piece in 10 
% of parcel  Allowed.  
Maximum 1 , 0 mm 
deep. Max 10 % 
surface of piece in 10 
% of parcel  Allowed  
3.3 Torn grain  Allowed.  
Maximum 0,5 mm 
deep on 10 % face in 
10 % of parcel  Allowed.  
Maximum 0,75 mm 
deep on 10 % face in 
10 % of parcel  Allowed.  
Maximum 1,0 mm 
deep on 10 % face 
in 10 % of parcel  
3.4 Raised grain  Allowed if light and 
can be removed by 
sanding  Allowed if light and can 
be removed by 
sanding  Allowed. Maximum 
1,0 mm above 
surface  
3.5 Chip marks  Allowed.  
Maximum 0.4 mm 
deep in 5% parcel  Allowed.  
Maximum 0.5 mm 
deep in 5% parcel  Allowed.  
Maximum 0.75 mm 
deep in 5% parcel  
3.6 Burn marks  Not allowed  Not allowed  Allowed  
3.7 Cutter marks  Not allowed  Not allowed  Allowed.  
Even and smooth 
to touch. Max 2 per 
25 mm  
7 Packaging  
Furniture components shall be packed in sets or as individual components and shrink wrapped. Each pack shall 
contain the same species, dimensions and colour.  
Shrink wrapped parcels shall be arranged on kiln dried and heat treate d wooden pallets in  accordance with 
applicable regulations  or their  equivalent to a height that will leave at least 50 mm  space at the top when the 
pallet is loaded into a container. The clearance between the floor  and the base of cross members of the pall et 
shall be at least 100 mm to facilitate mechanical  handling.  
Palletized products shall be covered with another moisture barrier  or a polyethylene film to prevent moisture 
from entering finished products and then strapped to make a parcel.  Shrink wrapped furniture components shall 
be packed into corrugated card boxes and  supported with foam against scratches and handling damage.  DRS 413:2019  
7                ©RSB 2019  - All rights reserved  
 8 Marking  
Each pack or bundle shall be labelled with the following information:  
a) Product  
b) Model  and d ate of manufacture  
c) Dimensions  
d) Number of pieces  
e) Quantity , expressed in m, m2 or m3 
f) Name of manufacturer  
g) Country of origin  
h) Destination  
i) Species  
j) Pack number  
k) Order/Contract number  
l) Weight  
m) Grade  
All containerized finished wood products shall be fumigated  against insects and other pest infestation wi th 
chemicals approved by the authority in charge of environment protection . 
 DRS 413:2019  
8                ©RSB 2019  - All rights reserved  
 Bibliography  
[1] GS 983 :2009 , Furniture – Specification for Furniture Component s 
[2] RS Xbb _2019 , Round and sawn timber – Nomenclature of timbers used in Rwanda  
ISPM 15 - 2017,  Regulation of wood packaging material in international trade  (Source: http://www.fao.org/3/a -
mb160e.pdf , query 2019 -03 06)  
ISO 9000:2015, Quality management systems – Fundamentals and vocabulary  
 DRS 413:2019  
ICS 97.140  
 
©RSB 2019 - All right s reserved