FINAL DRAFT UGANDA 
STANDARD  
  FDUS 844 
Second Edition  
2015 -mm-dd 
 
 
 Reference number  
FDUS 844: 2015 
© UNBS 2015   
  
Code of Practice for the  design, production, supply and 
provision  of wheelchairs and tricycles  
 FDUS 844: 2015  
ii © UNBS 2015  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provision s of a contract. Users are 
responsible for its correct application  
© UNBS 2015   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including phot ocopying and microfilm, without prior written 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: 256 41 4 505 995  
Fax: 256 41 4 286 123  
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  FDUS 844:2015  
© UNBS 2015  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Types of wheel chairs  ................................ ................................ ................................ ...........................  2 
4.1 General  ................................ ................................ ................................ ................................ ...................  3 
4.2 3-wheeler  ................................ ................................ ................................ ................................ ................  3 
4.2 4-wheeler  ................................ ................................ ................................ ................................ ................  3 
4.3 Hand powered tricycle  ................................ ................................ ................................ ..........................  3 
5 Framework for provision of wheelchairs by whee lchairs service  ................................ ....................  3 
5.1 General  ................................ ................................ ................................ ................................ ...................  3 
5.2 Recommended steps for provision of wheelchair services ................................ ..............................  4 
5.2.1  Referral and appointment  ................................ ................................ ................................ .....................  4 
5.2.2  Assessment  ................................ ................................ ................................ ................................ ...........  4 
5.2.3  Prescription  ................................ ................................ ................................ ................................ ............  4 
5.2.4  Product preparation  ................................ ................................ ................................ ..............................  4 
5.2.5  Fitting  ................................ ................................ ................................ ................................ ......................  4 
5.2.6  User instruction  ................................ ................................ ................................ ................................ ..... 4 
5.2.7  Follow -up, maintenance and repairs  ................................ ................................ ................................ ... 4 
5.3 Requirements for assessment and prescription to the end user  ................................ .....................  5 
5.3.1  Requirements for assessment  ................................ ................................ ................................ .............  5 
5.3.2  Good practice in assessment  ................................ ................................ ................................ ..............  5 
5.3.3  Good practice in prescrip tion ................................ ................................ ................................ ..............  5 
5.4 Requirements for the distribution of wheelchairs  ................................ ................................ .............  6 
6 Quality assessment of wheelchairs  ................................ ................................ ................................ ..... 7 
6.1 General  ................................ ................................ ................................ ................................ ...................  7 
6.2 Tests for strength, durability and safety  ................................ ................................ .............................  7 
Annex  A (normative)  Wheel cha ir designs  ................................ ................................ ................................ ... 21 
Annex  B (informative)  ................................ ................................ ................................ ................................ ...... 24 
 FDUS 844: 2015  
iv © UNBS 2015  – All rights reserved  
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Tourism, Trade and 
Industry es tablished under Cap 327 , of the Laws of Uganda.  UNBS is mandated to co -ordinate the 
elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Foo d Standards, and  
(c) the National Enquiry Point on TBT/SPS Agreements of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in  a given field or area and consists of representatives of 
consumers, traders, academicians, manufacturers, government and other stakeholders.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general pu blic for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
Committee membership  
This standard h as been  developed by the Transport and com munication Standards  Technical Committee  
(UNBS/TC 8). FDUS 844:2015  
© UNBS 2015  – All rights reserved  v 
 Introduction  
The standard aims to describe to designers, manufacturers, importers, suppliers and providers  of wheelchairs 
the standards required for the design specification, materials, and procedures for prescription, production  
provision and  follow -up of wheelchairs in Uganda.  
The standards written herein are descriptive, reflecting the performance value of each component of the 
designs of self -propelled wheelchairs and hand powered tricycles currentl y used in Uganda ( see Annex A). 
In addition , the standard  takes into consideration the rights of the end user to choose , appropriate functional 
assessment, prescription to best meet the identified needs and follow up to gather information about the 
product  and service, while encouraging wheelchair design developments or innovation within this field  
The functional performance of a wheelchair is determined by its design and features. Performance features 
include stability, manoeuvrability, pushing efficiency,  transferring, transport, and reliability. A wheelchair 
should be evaluated based on functional performance measures and the results made available with the 
wheelchair for providers. A wheelchair should meet or be selected based on the functional performan ce 
requirements of the user in the environment of use.  
 
 FINAL DRAFT UGANDA STANDARD  FDUS 844: 2015  
 
© UNBS 2015 – All rights reserved  1 
 Code of Practice for the design, production, supply and 
provision of wheelchairs and tricycles  
1 Scope  
This Final Draft Uganda Standard gives  guidelines for the design and manu facture/production, supply 
(including importation) and provision of wheelchairs and tricycles.  
This standard does not cover sports  and electrical  wheelchairs .  
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 7176 -8, Wheelchairs – Part 8: Requirements and test methods for static, impact and fatigue stren gths 
3 Terms and definitions  
For the purposes of this standard, the following terms and definitions shall apply . 
3.1 
appropriate wheelchair  
wheelchair that meets the user’s needs and environmental conditions; provides proper fit and postural 
support; is s afe and durable; is available; and can be accessed, maintained and sustained in the country at an 
economical price  
3.2 
manual wheelchair  
wheelchair that is propelled by the user or pushed by another person   
3.3 
wheelchair  
device to provide wheeled mobilit y with a seating support system for a person with a walking limitation  
3.4 
wheelchair provision  
overall term for wheelchair design, production and service  
3.5 
wheelchair service  
integral part of wheelchair provision concerned with providing users with appr opriate wheelchairs  
3.6 
wheelchair user  
person who uses or can benefit from using a wheelchair because his or her ability to walk is permanently or 
temporarily limited  FDUS 844: 2015  
2 © UNBS 2015  – All rights reserved  
 3.7 
rehabilitation  
process of restoration to the highest functional ability of an indivi dual with movement challenges to live a 
healthy and  better life 
3.8 
caregiver  
person who helps the wheelchair user propel the wheelchair due to the inability of the user to propel 
him/herself  
3.9 
assessment  
process of gathering information to identify  a wheelchair user’s individual needs for a prescribed product  that 
will optimise the user ’s potential  
3.10 
prescription  
analysing assessment results correctly to recommend for an appropriate wheelchair which is acceptable to the 
user 
3.11 
provision  
giving out  wheelchairs following a process of assessment, prescription fitting, user training and follow -up that 
meets or exceeds  an internationally agreed minimum  
3.12 
community workers  
people who offer rehabilitation services in the community  
3.13 
recognised supp lier 
supplier that is certified by the Ministry responsible for health or any other designated authority  
3.14 
CBR  
Community Based Rehabilitation  
3.15 
PWD  
People with Disability  
3.16 
NGO   
Non-Governmental Organisation  
4 Levels of wheelchair service provision  
There are three levels of service provision namely . 
a) basic level which  is for persons who can sit without any postural deformities or abnormality . Mobility 
and postural supports are provided through a well fitted wheelchair and seat cushion ; 
b) intermediate le vel which  is for persons with mild to moderate postural  deformities or tendancies . If 
unaddressed , these  deformities will limit comfort, health and function. Supportive seating is provided 
through individual modification to a b asic wheelchair, or a special ized seating system.  FDUS 844: 2015  
© UNBS 2015  – All rights reserved  3 
 c) advance d level which  is for persons with complex fixed postural deformities. Even with support many 
cannot sit normally. They require individual prescribed and customized wheelchairs to provide 
postural support and accommodate fixed de formities  
5 Types of wheel chairs  
5.1 General  
There are three categories of wheelchair designs : 
 3-wheeler chairs;  
 4-wheeler chairs ; and  
 hand powered tricycle s. 
5.2 3-wheeler  chairs  
5.1.1 The 3 -wheeler chairs shall be classified either as rigid terrain or Hu ckstep type.  
5.1.2 The rigid type has a castor wheel at the front  and is often provided to users living in rural settings 
where the terrain is very rough. This design provides a stable chair and is easy to perform rear -wheel balance, 
but is difficult to tr ansport.  
5.1.3 The Huckstep type has a castor wheel at the back . It is unable to be tipped backwards, has a wide 
external dimension but is difficult to side -transfer.  
5.2 4-wheeler  chairs  
5.2.1 The 4 -wheeler chairs shall be classified either as  foldable ty pe wheelchair or rigid type wheelchair . 
5.2.2 The foldable type is easy to transport in vehicles with easier side -transfers if provided with removable 
arm rests. This design provides a reduced stability over rough terrain . 
5.2.3 The r igid wheelchair is stable on even ground but may not be stable on rough terrain .  
5.3 Hand powered tricycle  
The tricycle  design feature cause less fatigue over distances  and some designs may allow carrying of items . It 
is not viable for use in restricted spaces, that is,  around  the home, office, school  and it very difficult to 
transport,  
NOTE Due to the diversity among wheelchair users, there is a need for different types of wheelchairs. No one 
wheelchair can meet the needs of all wheelchair users. Those providing  wheelchairs n eed an understanding of the needs 
and context of the intended wheelchair users as well as the rationale behind different wheelchair designs.  
6 Framework for  wheelchair service provision   
6.1 General  
The p urpose of  this standard  is to improve the way in wh ich wheelchair users receive wheelchairs and to 
ensure that the wheelchairs given to PWDs are appropriate.  
Wheelchair services  shall provide the framework to : FDUS 844: 2015  
4 © UNBS 2015  – All rights reserved  
 a) assess individual wheelchair user needs ;  
b) prescribe produce  and fit  an appropriate wheelchair ;  
c) instruct and educate wheelchair users and caregivers on the correct use and maintenance of a 
wheelchair ;  
d) provide on -going follow up , repair and maintenance of a wheelchair ; and  
e) referral to other services where appropriate.  
6.2 Recommended steps for provis ion of wheelchair services  
6.2.1 Referral and appointment  
The system of referral will depend on the service. Wheelchair users may self -refer or be referred through 
networks made up of government or NGO s health and rehabilitation workers or volunteers work ing at 
community, district or regional level.  
6.2.2 Assessment   
Each wheelchair user requires an individual assessment.  
6.2.3 Prescription  
Using the information gained from the assessment , a wheelchair prescription is developed. The prescription 
details th e wheelchair type, size, special features, and modifications. Also detailed is the instruction the 
wheelchair user needs to effectively use and maintain the wheelchair.  
6.2.4  Ordering  
The wheelchair shall be ordered from a  recognised supplier . 
6.2.5  Product prep aration  
The wheelchair service provider prepares the wheelchair for the initial fitting. Depending on the  prescription , 
this may include assembly, and possible modification, of products supplied by manufacturers or fabrication of 
products in the service w orkshop.  
6.2.6 Fitting  
The wheelchair user tries the wheelchair . If modifications or postural support components are required, 
additional fittings may be necessary.  Final adjustments are made to ensure that the wheelchair fits the user 
and is correctly set -up.  
6.2.7 User instruction  
The wheelchair user and care -givers are instructed on how to safely and effectively use and maintain the 
wheelchair.  Service providers shall provide instruction manu als to the users  in the language that is understood 
by the use r or caregiver.  
6.2.8 Follow -up, maintenance and repairs  
Follow -up appointments are an opportunity to check wheelchair fit and provide further training and support. 
The timing depends on the needs of the wheelchair user, and what other services are availab le to them. The 
service should  also offer maintenance and repairs, for technical problems that cannot be easily solved in the FDUS 844: 2015  
© UNBS 2015  – All rights reserved  5 
 community.  Wheelchair services providers are encourage d to partner with organisation that offer CBR service 
so that users are foll owed -up and wheelchairs are maintained.  
6.3 Requirements for assessment and prescription to the end user  
6.3.1 Requirements for assessment  
In the provision of wheelchairs for PWDs , each individual shall receive the appropriate assessment by a 
trained healt h professional or anyone who is trained in assessment and prescription registered  by the Ministry  
responsible for health . These professionals shall include orthopaedic surgeons, medical officers, orthopaedic 
officers, occupational therapists, physiotherapi sts, orthopaedic technologists and wheelchair technologists. . 
6.3.2 Good practice in assessment  
6.3.2.1  Assessments should be carried out in a private, quiet and clean space. This may be a dedicated 
space within the hospital or workshop, at another healthc are or community facility, or at the wheelchair user’s 
home.  
6.3.2.2  Assessments should be carried out by personnel with both appropriate clinical and technical 
training.  
6.3.2.3  Equipment for the assessment should be readily available, including an assess ment bed (plinth, 
mat or table), measuring tape, goniometers, foot blocks and infection control supplies.  
6.3.2.4  Assessment should take  into consideration the wheelchair user’s physical condition; home, 
school, work and other environments of use; lifestyl e; size and age.  
6.3.2.5  Assessments should be clearly documented on an approved assessment form and filed for future 
reference.  
6.3.2.6  Where a service  provider  is unable to meet the wheelchair user’s needs due to lack of an 
appropriate product, or perso nnel with sufficient skills , the service provider either:  
a) refers the wheelchair user to another service provider that is staffed and equipped to serve the 
wheelchair user ;  
b) hosts outreach visits of more qualified personnel ; or 
c) documents the wheelchair user ’s needs to help build a picture of un -met needs to guide future service 
development.  
6.3.3 Good practice in prescription  
6.3.3.1  Wheelchair service personnel should write up assessment and prescription notes, immediately 
after each appointment.  
6.3.3.2  Each wheelchair prescription is documented either on the assessment form  or on the prescription 
form. The prescription details  the following : 
a) the type and dimensions  of wheelchair ;  
b) any additional components required such as  pressure relief seat cushion ;  
c) any modifications or custom components required ; and 
d) the information or skills that the wheelchair user needs to know, or be able to perform, before leaving 
the service with their new wheelchair . FDUS 844: 2015  
6 © UNBS 2015  – All rights reserved  
 6.3.3.3  The importance of features is prioritised, to help to make the most appropriate choice from what 
may be a limited range of wheelchairs available.  
6.3.3.4  Wheelchair users are given the opportunity to see, and where possible, try sample wheelchairs, 
cushions and postural support components. This assists wheel chair users and personnel to make the 
prescription.  
6.3.3.5  Service providers should give wheelchair users an estimate of when their wheelchair will be 
ready. Where possible, an appointment for the wheelchair user’s fitting is made at the time of making th e 
prescription.  
6.4 Requirements for the provision of  wheelchairs  
6.4.1 No wheelchair should be given out to users without proper assessment, prescription and fitting by  the 
professionals and persons trained in wheelchair assessment, prescription and fitti ng. 
6.4.2 Standard provision  of wheelchairs  to user shall incorporate demonstration of any adjustable or 
removable part s, the brake system and information regarding care and maintenance.  The service provider 
shall ensure that the wheelchair is provided wit h either a foam cushion of at least 50  mm or pressure relief 
cushion or postural control cushion.  
6.4.3 It is recommended that irrespective of the method of provision : 
a) the wheelchair service provider should have the capacity to provide the wheelchairs in a reasonable 
and responsible manner ; 
b) the provision  is based  on assessment of the situation in the country or the district and considers the 
impact on local wheelchair producers and service providers ; 
c) procured wheelchairs  meet or exceed the national or inte rnational standards on wheelchairs and be 
appropriate for the environment of use ; 
d) wheelchairs are provided following a provision process that meets or exceeds nationally  or 
internationally  agreed minimum requirements for service provision, including requir ements for 
assessment, fitting , user training and follow -up; and  
e) providers coordinate their  service with the Ministry responsible for health and referral rehabilitation 
workers at all levels .  
6.4.4 The main factors that need to be considered in wheelchai r supply include : 
a) reliability ; 
b) durability and performance of the wheelchair ; 
c)  types of available wheelchairs ; 
d) availability of local repair  services ; 
e) economic empowerment ; 
f) affordability ; 
g) weight ; 
h) responsiveness of the  provider  to the needs of wheelchair use rs; 
i) coordination of supply with an overall plan for wheelchair provision ; and FDUS 844: 2015  
© UNBS 2015  – All rights reserved  7 
 j) cosmetic value . 
7 Quality assessment of wheelchairs  
7.1 General  
Wheelchairs should be safe and effective for their users. When a wheelchair fails, the user is not only at risk o f 
injury, but he or she may not be able to go anywhere or do anything until the wheelchair is fixed or replaced.  
7.2 Tests for  static  strength, impact and fatigue  
7.2.1 Tests should be performed on each wheelchair design. As a minimum, it is therefore reco mmended 
that all wheelchairs produced locally or imported shall meet the requirements laid down in this standard   when 
tested in accordance with ISO 7176 -8 to ensure  quality of wheelchairs.  
7.2.2 The tests laid down in this standard should be used togethe r with ISO standards for  
 stability,  
 brake effectiveness,  
 overall dimensions , 
 weight,  
 turning space, and  
 seating dimensions.  
7.2.3 Carry out each test twice, in the order shown. Complete tests take about 2  h - 3 h per chair. Before 
loading the chair, set a ll adjustable settings to the middle setting. When the chair is loaded to 90  kg, test the 
correct weight distribution by lifting the front of the chair using a spring balance hooked under the front of the 
fixed footplate (tie folding plates together for th is test). The lifting force to raise the front wheels should be 
about 20  kg. Redistribute the weight accordingly.  
Since deformations are the criteria for passing or failing these tests, the key dimensions in 7.2.4 shall  be 
measured and recorded before test ing and then re -measured according to the testing plan. Deformation is to 
be measured as 'permanent deformation' after the removal of the load.  
7.2.4 During m easurement recording , use a tape measure or ruler to measure the distance from  
a) rear wheel -to-rear wheel at front (toe -in/out measuring tool) , 
b) rear wheel -to-rear wheel at rear (toe -in/out measuring tool) , 
c) rear wheel -to-rear wheel at top (measure camber against a door frame) , 
d) rear wheel -to-rear wheel at bottom (draw guide lines on the floor) E , 
e) right han d castor wheel axle to rear most point on right hand bottom rail , 
f) right hand castor wheel axle to rear most point on left hand bottom rail , 
g) left hand castor wheel axle to rear most point on left hand bottom rail , 
h) left hand castor wheel axle to rear most po int on right hand bottom rail , FDUS 844: 2015  
8 © UNBS 2015  – All rights reserved  
 i) right hand foot -rest mounting point (end of front rail) to rear most point on right hand bottom rail , 
j) right hand foot -rest mounting point (end of front rail) to rear most point on left hand bottom rail , 
k) left hand foot -rest mo unting point (end of front rail) to rear most point on left hand bottom rail , 
l) left hand foot -rest mounting point (end of front rail) to rear most point on right hand bottom rail , 
m) side-to-side between side frames at:  
 end of front rails ; 
 castor barrels ; 
 rear most point on right hand bottom rail ; 
 rear most point on right hand bottom rail ; 
 push handles ; 
 seat front ; and  
 seat rear . 
To speed up the job of re -measuring every time, a set of welding rods can be cut to the lengths which need to 
be measured.  
Test 1  
 
 
Measure  
 
  To simulate the effect of a hitch hiker riding on the footplate  
With the chair standing on the bench (and clamped down), hang 90kg from the 
centre point of each foot rest and observe any deformation.  
Deformation of : footrest and footrest angle  
    footrest attachment point  
    end of front/bottom rail around mounting  
 
 
 
 
 
  
 
 Result  
 
 
 
 
  
 
 
 
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© UNBS 2015  – All rights reserved  9 
 Test 2  a) 
 
 
 
Measure  To simulate the effect of lifting a person in their chair holding the arm 
rest 
Armrest which swing away or are removable  should loc k in place, hang 
weighted chair from the centre of the arm rest the lock should hold 90  kg  
 
Whether the lock holds, any deformation  
 
 
 
 
 
 
 
 
 
 Result  
 
 
 
 
Test 2 b)  
 
 
Measure  To simulate removing the armrest for transferring  
With the armrest un -locked,  use a spring balance to pull on the armrest, the 
forces required to remove or swing it away should be less than 4.5  kg  
Force required  
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 FDUS 844: 2015  
10 © UNBS 2015  – All rights reserved  
 Test 3  
 
Measure  To simulate the effect of lifting a person in their chair holding the 
footplate   
With helper sitting in the chair, lift fixed footplate from the centre using the 
spring balance with force of 45  kg  
Deformations of : footrest attachment  
    end of front rail around footrest mounting  
    footrest and footrest angle  
 
 
 
 
 
 
 
 
 
 Result  
 
 
 
 
Test 4  
 
 
Measure  To simulate lifting the footplate for transferring  
Lift folding footplate from the free end using the spring balance the force 
required should be less than 4.5  kg  
Force required  
 
 
 
 
 
 
 
 
 
  
 
 
 
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© UNBS 2015  – All rights reserved  11 
 Test 5  
 
 
Measure  To simulate the effect of lifting a person in their chair holding the push 
handle  
With 90  kg strapped in the chair hang the weighted chair from one push 
handle, repeat with opposite handle (rope should be tied around the hand grip)   
Deformation of:  Backrest  
    Backrest fabric  attachment points  
    Push handle   
    Security of hand grip (will its slip off)  
    Backrest mounting points  
    Push handle mounting points  
 
 
 
 
 
 
 
 
 
 
 
 Result  
 
 
 
 
  
 
Test 6  
 
 
 
Measure  To simulate the effect of pressure relief  
Ask your helpers t o sit in the chair, place their hands on middle of the armrest 
and lift themselves fully out of the seat repeat, lift  putting all pressure on one 
arm rest   
Deformation of:  Backrest  
    Backrest fabric attachment points  
    Armrest    
    Backrest mount ing points  
    Armrest mounting points  
 
 
   
 
 
 
 
 
  
 
 
 
 
 
 FDUS 844: 2015  
12 © UNBS 2015  – All rights reserved  
 Test 7  
 
Measure  To simulate the effect of twist  
With helper holding down one side frame, lift the front of the opposite  side 
frame using the spring balance with force of 35  kg  
Deformation of:  frame alignment  
 
 
 
 
 
 
 
 
 
 Result  
 
 
 
 
Test 8  
 
Measure   To simulate the effect of someone dropping the chair  
Drop the empty chair from a height of 40cm on to each rear wheel when 
opened and folded  
Deformation of : Frame alignment  
    Castor assembly  
    Rear wheels  
 
 
 
 
 
 
  
 
 
 
 
 
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© UNBS 2015  – All rights reserved  13 
 Test 9  
 
 
Measure  To simulate the effect of single footrest impact  
With 90  kg strapped in the chair push one footrest or front of chair into a solid 
wall at 1.5  m/sec (a fast walking pace is 15  m in 10 s) release chair moments 
before it hits the curb  
Deformation of:  Footrest and footrest angle  
    Footrest attachment point  
    End of front rail around footrest mounting  
    Frame alignment  
 
 
 
 
 
 
 
 
 Result  
 
 
 
 
 
 
 
Test 10  
 
 
Measure  To simulate the effect of a person wheeling  off an uneven curb  
With 75  kg strapped in the chair, wheelie slowly off the sloped edge of a 10 
ramp so that the lose wheel drops 18  cm (tight spokes with three cross overs 
will help strength)   
Deformation of:  frame alignment  
    Rear wheels  
    Rear w heel alignment camber, toe -in toe out  
    Rear axles  
    Rear axles sleeve and mounting point  
    Backrest  
    Backrest fabric attachment points  
    Seat fabric attachment points  
    Backrest mounts points    
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 FDUS 844: 2015  
14 © UNBS 2015  – All rights reserved  
 Test 11  
 
 
Measure   To sim ulate the effect of single castor impact  
With 90  kg strapped in the chair, push one castor wheel into an un -mountable 
solid curb at 1.5  m/sec (a fast walking pace is 13  m in 10 s) release chair 
moments before it hits the curb   
Deformation of : Frame  alignm ent  
    Castor wheels  
    Castor axles  
    Castor barrel  
    Castor fork  
    Backrest fabric   
    Backrest mounting points   
 
 
 
 
 
 
 Result  
 
 
 
 
 
 
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 Test 12  
 
 
Measure  To simulate the effect of a person wheeling off a  high curb  
With 90  kg strapped in th e chair, wheel slowly off a 30  cm curb so that the rear 
wheels touch the ground first (tight spokes with three cross overs will help 
strength)  
Deformation of:  frame alignment  
    Rear wheels  
    Rear wheel alignment camber, teo -in toe out  
    Rear axle s  
    Rear axles sleeve and mounting point  
    Backrest  
    Backrest fabric attachment points  
    Seat fabric attachment points  
    Backrest mounts points    
 
 
 
 
 
 
 Result  
 
 
 
 
 
 
Test 13  
 
 
Measure  To simulate the effect of a person leaning into the backrest  
Take the rear wheels off the chair and place the frame on its side and clamp it 
over the edge of a bench carefully suspend 90kg onto the backrest tube, 30cm 
from the rear axle point  
Deformation of:  frame alignment     
    Backrest  
    Backrest f abric attachment points  
    Seat fabric attachment points  
    Backrest mounts points    
 
 
 
 
 
 
 
  
 
 FDUS 844: 2015  
16 © UNBS 2015  – All rights reserved  
 Test 14  
 
 
Measure  To simulate the effect of side force on a wheel and axle  
Keeping the frame on its side, replace one of the rear wheels so that the whee l 
is horizontal carefully suspend 90  kg from the wheel rim  
Deformation of : Rear wheel  
    Rear axles  
    Rear axl e sleeve and mounting point  
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
Test 15  
 
 
Measure   To simulate the effect of side force on a castor fork bolt  
Remove the cas tors fork, place it in strong vice and slip 12 cm length of strong 
tube over the fork bolt using  a spring balance apply 20  kg of force at 90 to the 
free end of the tube  
Deformation of:  Fork bolt  
    Fork   
 
 
 
 
 
 
  
 
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 Item General common considerations  
Design 
Features  Due to the diversity among wheelchair users, there is a need for different types of wheelchairs. No one 
wheelchair can meet the needs of all wheelchair users. Those selecting wheelchairs need an understanding 
of the needs and context of th e intended wheelchair users as well as the rationale behind different wheelchair 
designs.  
Caster 
Wheel(S)  The caster wheel structure, including tyre should be manufactured from a shock -absorbent material that can 
withstand operational loads without failur e at an ambient temperature of 35 °C minimum. Castor barrel is 
made from mild -steel pipe of 15  mm or a material of such quality that ensures it can withstand the same 
operational loads without failure. Castor fork should spin freely at 90C to the ground.   It is recommended that 
the caster barrel is of the same dimension as the rear hub tube. Castor wheel should spin freely perpendicular 
to the ground and should not wobble from side to side. All nuts and bolts attaching castor wheel to main beam 
should have  plain washers between bolt head and caster wheel and between nut and castor wheel and 
should be tight and correctly mounted. The ratio of the circumference of castor wheel to the rear wheel 
circumference should not reduce the stability of the chair nor im pede its propulsion. (is there a standard ratio)  
Seat Surface of seat should remain smooth with no protruding fastenings. Minimal seat dimensions are width 
300mm, length 300mm.( for adults only). If fixed or removable armrests are not fitted, protection f rom 
sheering force of rear wheels will be provided. The seat material will be securely fastened to the frame to 
ensure no movement during load bearing.  NB. Optimum fitting of seat for end user should ensure 20mm 
space either side of thighs and arm rests ( if fitted), and 25mm from front edge of seat and back of knee. Exact 
dimensions of seat will be determined by the individual assessed need of user, and the relation between 
height, width, and length will vary depending on body size and shape.  
Backrest  Backrest is fabricated in water -resistant material, securely fastened to frame with suitable fastening providing 
nil protrusion from back rest material at either side edge. Minimal backrest width is in line with seat 
dimensions. Optimum fitting of backrest fo r end user should consider free movement of shoulder blades if 
chair is to be self -propelled.  Back rest should support the truck with hips at 90 degrees. The height should 
depend on the person's needs.  
Frame  The frame is made from mild steel pipe of mini mum 22mm or a material of a quality to ensure it can withstand 
the same operational loads without failure. It is recommended that the diameter of the frame is the same as 
the dimension of the caster barrel and hub tubes. The frame should have a minimal gro und clearance of 
50mm. Nuts, paintwork and welds will have no cracks or holes, and there will be no sharp edges to the finish.  
Propelling 
Wheels (Rear 
Wheels)  Rear wheels are attached to the main frame by the hub, parallel to the frame (no 'toe -in toe -out'). An equal 
camber both sides of the rear wheel may be recommended to improve performance. Wheels are 
manufactured from locally available rims, inner tubes, and tyres. In materials resistance to an ambient 
temperature of 35 C minimum. Rear wheel diameter shall be minimum 600mm inflated. Rear wheel must spin 
freely in alignment to the castor wheel and axle bolts are tight but not over tight. All nuts, axle bolts and 
washers attaching the rear wheel onto the main frame must be tight and correctly fitted. The  rim should run 
'true' with the rim centred to the axle and hub. All spokes must be tight. A clearance of minimal 20mm is 
required between push -rim and wheel. The finish needs to be smooth and spot free. Push -rims need to be 
mild- steel pipes of minimum di ameter 16 mm.  
Footplates  The foot rest shall be positioned to provide support to two thirds of the foot with the knee angle not less than 
70° and should not wobble. The surface of the footrest shall be covered in a slip -resistant material with no 
sharp ed ges. The minimal ground clearance shall be 50mm.  
Cushion(S)  Minimal provision is with a 50mm foam cushion, if additional pressure relief is required assessment by an 
Orthopedic Surgeon, Orthopedic officers, Occupational Therapist, Physiotherapist, or Whee lchair 
Technologist is recommended. All cushions will be covered with water -resistant material with no wrinkles or 
joins in the top of the cover.  
Brake(S)  Brake adjustment must be accessible. Brake design is to be of a type to enable ease of operation by the user. 
No movement of the wheels will be evident when the brakes are applied. On application the brake must not 
unlock with a backward movement of the wheelchair.  FDUS 844: 2015  
18 © UNBS 2015  – All rights reserved  
  
 Four wheelers – Foldable  Four wheelers - Rigid  
Design Features  Foldable Imported - easy to transport in vehicles 
and is often regarded as aesthetically pleasing, 
with easier side -transfers if provided with 
removable arm rests. This design provides a 
reduced stability over rough terrain however 
spare parts are not available locally. Folda ble 
Locally Made – as above, however spare parts 
are available locally.  The rigid wheelchair is stable on even ground but may 
not be stable on rough terrain.  
 
 
Caster Wheel(S)  Wheelbase will be determined by the stability of 
the chair when tilted to an a ngle so that the chair 
remains upright .and usable. The height of the 
main beam should not impede transfers  Wheelbase will be determined by the stability 
of the chair when tilted to an angle so that the 
chair remains upright .and usable. The height 
of the main beam should not impede transfers.  
 
Seat  The seat material should be water -resistant and 
fitted across the frame should not sag more than 
50 mm when subjected to a uniformly distributed 
maximum load of 100 kg.  The seat material should be water -resista nt 
and fitted across the frame should not sag 
more than 50 mm when subjected to a 
uniformly distributed maximum load of 100 kg.  
Backrest  The backrest material should withstand repeated 
loading overtime of a uniformly distributed load, 
to a sag of no more than 50 mm.  The backrest material should withstand 
repeated loading overtime of a uniformly 
distributed load, to a sag of no more than 50 
mm. 
Frame  For folding chairs, all components should be 
fitted so that they enable free and easy folding.  Rigid  
Prope lling Wheels 
(Rear Wheels)  Rear wheels are attached to the main frame 
parallel to the frame Rear wheel must spin freely 
in alignment to the castor wheel. A clearance of 
minimal 20mm is required between push -rim and 
wheel. Push -rims need to be mild - steel p ipes of 
minimum diameter 16 mm  Rear wheels are attached to the main frame 
parallel to the frame Rear wheel must spin 
freely in alignment to the castor wheel. A 
clearance of minimal 20mm is required 
between push -rim and wheel. Push -rims need 
to be mild - steel pipes of minimum diameter 16 
mm 
Footplates  Mild steel paint them 1 -1.5 mm thickness. Can 
be paddedif needed with water resistant materil.  
Has to be flexible and adjustable.  Mild steel paint them 1 -1.5 mm thickness. Can 
be padded if needed with water r esistant 
material.  Has to be flexible and adjustable or 
fixed  
Cushion(S)  Should cover the seat base, removable and easy 
to clean. About 5 inch thickness Chip material 2 
inch and soft foam 3 inch  Should cover the seat base and easy to clean. 
About 5 inch thickness Chip material 2 inch 
and soft foam 3inch  
Brake(S)  Adjustments must be easily applied.  Adjustments must be easily applied.  
 
3 Wheelers  –   
 Design Features  Rigid (rural) wheelchair is often provided to users living in rural settings where the t errain is very 
rough. This design provides a stable chair and is easy to perform rear -wheel balance, but is difficult 
to transport.  
Caster Wheel(S)  Wheelbase will be determined by the stability of the chair when tilted to an angle so that the chair 
remain s upright .and usable. The height of the main beam should not impede transfers.  
Seat  FDUS 844: 2015  
© UNBS 2015  – All rights reserved  19 
 Backrest  The backrest material should withstand repeated loading overtime of a uniformly distributed load, 
to a sag of no more than 50 mm.  
Frame  Rigid  
Propelling Whee ls (Rear 
Wheels)  Rear wheels are attached to the main frame by the hub, parallel to the frame (no 'toe -in toe -out'). 
An equal camber both sides of the rear wheel may be recommended to improve performance. 
Wheels are manufactured from locally available rims , inner tubes, and tyres. In materials 
resistance to an ambient temperature of 35◦C minimum. Rear wheel diameter shall be minimum 
600mm inflated. Rear wheel must spin freely in alignment to the castor wheel and axle bolts are 
tight but not over tight.  
Footplates  Mild steel paint them 1 -1.5 mm thickness. Can be padded if needed with water resistant material.  
Has to be flexible and adjustable or fixed  
Cushion(S)  Should cover the seat base and easy to clean. About 5 inch thickness Chip material 2 inch and s oft 
foam 3inch  The cover material should be tailored to the needs of the user.  
Brake(S)  Adjustments must be easily applied.  
 
3 Wheelers - Huckstep  
 Design Features  Huckstep type - offers a durable design and provides easier propulsion over distances. Th is design is 
well known in Uganda and can be repaired locally. It is unable to be tipped backwards, has a wide 
external dimension but is difficult to side -transfer.  
Caster Wheel(S)  The casters should spin freely in the fork and should not wobble must be strong and durable.  
Seat Rigid  
Backrest  Rigid should support the trunk  
Frame  Rigid  
Propelling Wheels 
(Rear Wheels)  The rear wheels should be positioned so that when the wheelchair user holds the top of the push rim 
the elbow is bent at 90 degrees  but Huckstep should aim at 90 degrees. It  has a best push with larger 
strides                                                                                                                                                                                     
Footplates  Mild steel paint them 1 -1.5 mm thickness. Can be padded if needed with water resistant material.  Has 
to be flexible and adjustable or fixed  
Cushion(S)  Should cover the seat base and easy to clean. About 5 inch thickness Chip material 2 inch an d soft 
foam 3  inch The cover material should be tailored to the needs of the user . 
Brake(S)  One brake operates both wheels concurrently  
 
3 Wheelers - Hand powered  
 Design 
Features  May have a design feature that allows carrying of items and is reported to cause less fatigue over 
distances. Spare parts are available locally. It is not viable for use in restricted spaces, i.e. around the 
home, office, school, very difficult to transport, etc.  
Caster 
Wheel(S)  2 wheels in front and a chain drive  
Seat Rigid  
Backrest  Rigid  
Frame   A main beam is made from mild -steel pipe of 38mm (minimum) or a material of a quality to ensure it 
can withstand the same operational loads without failure.  FDUS 844: 2015  
20 © UNBS 2015  – All rights reserved  
 Propelling 
Wheels (Rear 
Wheels)   Rear wheels are attached to the main fra me by the hub, parallel to the frame (no 'toe -in toe -out'). An 
equal camber both sides of the rear wheel may be recommended to improve performance. Wheels are 
manufactured from locally available rims, inner tubes, and tyres. In materials resistance to an a mbient 
temperature of 35 C minimum. Rear wheel diameter shall be minimum 600mm inflated. Rear wheel 
must spin freely in alignment to the castor wheel and axle bolts are tight but not over tight. All nuts, axle 
bolts and washers attaching the rear wheel ont o the main frame must be tight and correctly fitted. The 
rim should run 'true' with the rim centr ed to the axle and hub. All spo kes must be tight.  
Footplates   The surface of the footrest shall be covered in a slip -resistant material with no sharp edges. T he 
minimal ground clearance shall be 50mm  
Cushion(S)   Minimal provision is with a 50mm foam cushion, if additional pressure relief is required assessment by 
an Orthopaedic Surgeon, Orthopaedic officers, Occupational Therapist, Physiotherapist, or Wheelcha ir 
Technologist is recommended. All cushions will be covered with water -resistant material with no 
wrinkles or joins in the top of the cover.  
Brake(S)   Brake adjustment must be accessible. Brake design is to be of a type to enable ease of operation by 
the user. No movement of the wheels will be evident when the brakes are applied. On application the 
brake must not unlock with a backward movement of the wheel. The brake must not impede transferring  
 
 FDUS 844: 2015  
© UNBS 2015  – All rights reserved  21 
 Annex  A 
(normative)  
 
Wheel chair designs  
 
 
 FDUS 844: 2015  
22 © UNBS 2015  – All rights reserved  
 
 
 
 FDUS 844: 2015  
© UNBS 2015  – All rights reserved  23 
 
 FDUS 844: 2015  
24 © UNBS 2015  – All rights reserved  
 Annex B 
(informative)  
These guidelines have been developed to assist wheelchair builders to test wheelchairs with fixed or folding 
frames, in their own workshops. Testing wheelchairs will help establish minimum acceptable criteria for 
wheelchair builders and suppliers throughout the world.  
Some wheelchair builders have been using these tests for several years and have found that if their chairs 
pass these tests, then they will experience a number of benefits. For the wheelchair builder, the benefits 
include:  
- Knowing that the wheelchairs which they build are reaching an acceptable and recognized standard  
- Less wheelchairs are returned to the workshop because of faults  
- Better quality will result in more clients and higher sales  
- Putting pressure on wheelchair impo rters and other manufacturers to reach the same standards  
- Reducing the justification for NGOs to import second -hand wheelchairs  
- Increasing the justification for asking NGOs, Government Offices and individuals to pay the actual 
cost of locally produced whee lchairs.  
- The benefit for the user is a greater opportunity to achieve mobility, independence and higher quality 
of life.  
Each test should be repeated once, failure is likely to have occurred if the dimensions changed in one 
direction after the first test, and then continued to change in the same direction after the second test. Any 
failure could be catastrophic so try to correct even the smallest failure and re -test that area. It is recognised 
that these tests for impact and strength do not directly test fa tigue failure of structural materials or joints. For 
fatigue tests, we recommend that the chair is loaded with 150  kg and towed at speed over rough terrain. This 
is very un -scientific but very worthwhile  (make sure that no more than 20  % of the total load is on the front 
wheels).  Naturally, passing these tests will not necessarily mean that the wheelchairs being built are of good 
design, therefore these tests should be used in conjunction with other information contained in ISO wheelchair 
standards for: static stability, brake effectiveness, overall dimensions, weight, turning space, seating 
dimensions . FDUS 844: 2015  
© UNBS 2015  – All rights reserved  25 
 Bibliography  
WHO Guidelines on the provision of manual wheelchairs in less resourced settings , 2008  
 FDUS 844: 2015  
© UNBS 2015 – All rights reserved  26 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in t he figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Stand ards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in  accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained f rom the Director, Uganda 
National Bureau of Standards.  
 
 FDUS 844: 2015    
 
ICS nn.nnn.nn  
Price based on nn pages  
© UNBS 2015 – All rights reserved