Microsoft Word - Anthropometry of Indian Manual Wheelchair Users - Vikas Sh\\205

12 Pages·2007·0.23 MB·English

Anthropometry of Indian Manual Wheelchair Users: a validation study of Indian
accessibility standards
- Vikas Sharma, Access Consultant, AccessAbility, India

Statement of Problem
There are several accessibility guidelines in India that provide slightly differing
anthropometric standards and design recommendations. However, it is unclear whether
any of the standards available are based on original anthropometric research done on the
Indian disabled population. Despite advancements in assistive technology and increasing
availability of customised wheelchairs, there has been no study to validate the Indian
accessibility standards and to check if they continue to meet the functional
anthropometric needs of Indian manual wheelchair users.

Objective
The overall aim of the study is to establish whether the Indian accessibility standards
continue to meet the anthropometric needs of the current population of manual
wheelchair users. This will identify if a need for further research in the anthropometrics
of Indian disabled population or a review of the existing accessibility codes is indicated.

Methodology
The study aims to review the existing literature to analyse the current anthropometric
recommendations in the Indian accessibility standards and guidelines and also compare
these with the corresponding publications produced by the International Organisation for
Standardisation (ISO) and those in use in UK and USA. It is intended to investigate if the
Indian standards were based on any original anthropometric research done on the local
population of Indians with disabilities.

Static and Dynamic anthropometric data of a sample group of 15 Indian manual
wheelchair users will be collected during the study to identify the design needs of the
current population. These findings will then be compared with the existing Indian
standards and a critical analysis done.

Summary of Literature Review
Person with Disabilities Act (1995) is a landmark legislation that recognises the rights of
Indians with disabilities and creates opportunities for equal participation in all
government run infrastructure and services. There are several access standards and
guidelines published by the different departments of the Government of India but the Act
does not comment on them and does not endorse any particular publication.

Table: Indian Accessibility Standards and Guidelines
Name Developed by Published Revised Enforcement
IS 4963: Recommendations Bureau of Indian 1968 1992 Standard
for Buildings and Facilities Standards (BIS)
for the Physically
Handicapped
National Building Code BIS 1970 2005 Standard
IS 7454: Rehabilitation BIS 1974 1997 Standard
Equipment-Wheelchairs,
Folding, Adult Size –
Specification
Guidelines and Space Central Public 1998 1998 Guideline
Standards for Barrier Free Works Department
Built Environment for (CPWD)
Disabled and Elderly
Persons
Planning a Barrier Free Office of Chief 2001 2001 Guideline
Environment Commissioner for
persons with
disabilities (CCD)
New Delhi Building Delhi Municipal 2005 --------- Standard
Byelaws Corporation

The following tables illustrate a comparative analysis of Guidelines and Standards for
accessible design used in India, UK and USA. Also comparison has been done with the
standard ‘ISO 7193: Wheelchairs - Maximum overall dimensions’ and ‘ISO/ TR 9527:
Building Construction – Needs of disabled people in buildings – Design guidelines’
published by the International Organisation for Standardisation. For USA ‘Americans
with Disabilities Act Accessibility Guidelines’ (ADAAG) were reviewed whereas for
UK, ‘BS 8300: Design of buildings and their approaches to meet the needs of disabled
people — Code of practice’ and ‘Inclusive Mobility’, which are accessibility guidelines
produced by the Department of the Environment, Transport and the Regions (DETR)
were included in this study. The analyses was limited to wheelchair dimensions, clear
floor area provisions, space requirements for maneuvering, knee and toe clearances and
reach limits.

The columns in light green background represent the Indian anthropometric
recommendations and the columns in lavender background represent the international
ones. Figures in red indicate exact matches and figures in blue indicate close similarity
between the Indian and international access standards and guidelines. The various exact
matches and several close similarities for the dimensional data clearly hint that the Indian
recommendations may be a negotiated settlement of international minimum guidelines
and requirements.

Table: Comparison of Structural Anthropometry of wheelchair users (in mm)
Country India UK USA ISO
Standard BIS (IS CPWD CCD Inclusive ADAAG ISO
7454 & IS Mobility 7193
4963) (DETR 1999) & ISO
& BS 8300 9527
Wheelchair Measurements
Unoccupied width 650 – 720 750 680 750 660 700
Occupied width X 800 900 800 760 800 –
900
Unoccupied length 1000- 1050 1200 1200 1065 1200
1100
Occupied length X 1200 1150 – 1250 1220 1250
1250
Handle height 910 – 950 X 920 X 915 1090
Eye height X X 1100 – 960 – 1250 1090 – X
1300 1295
Total seated height X X X 1300 – 1400 X 1350
Armrest height 700 – 740 X 760 794 760 X
Seat height 480 – 510 X 480 – 460 – 490 485 500
500
Knee height X X 675 691 685 X
Toe height X X 200 X 205 X
Knee clearance depth X X X 260 280 X
Toe clearance depth X X X X 150 X
Combined knee + toe 400 – 350 480 490 X 600
clearance depth 450

Table: Comparison of Functional Anthropometry of wheelchair users (in mm)
Country India UK USA ISO
Standard BIS (IS CPWD CCD Inclusive ADAAG ISO
7454 & IS Mobility 7193
4963) (DETR 1999)
& BS 8300
Reach Ranges – Forward
High 1350 – 1200 1200 X 1220 1200
1600
Low X 400 400 X 380 400
Obstructed high 715 - 830 1100 1100 1000 – 1150 1120 X
Obstructed low X X X 650 X X
Reach Ranges – Lateral
High 1350 – 1300 1300 1060 – 1170 1370 X
1770
Low X 250 250 630 – 665 230 X
Obstructed high X 1200 1200 X 1220 X
Maneuvering Clearances
Width – 90◦ L-turn X X X 1450 - 1550 915 X
Circular diameter – 1500 1500 – 1800 1600 - 2150 1525 1500
360◦ turn 2000
Review of research behind developing the standards reveals that the Indian standards,
except IS 7454, and accessibility guidelines are not based on any original anthropometric
research done on the local disabled population. The Indian Standard IS 7454 was based
on research done on static anthropometry of unoccupied wheelchairs in late 1974.
Advances in wheeled mobility technology, the ongoing demographic shift towards an
ageing society, and changes in stature of the population due to nutritional improvements
and genetic shift since that time suggest that the Indian standards may be out of date.
Recent research on the anthropometry of wheeled mobility users has been conducted in
Australia, the United Kingdom and Canada. Most of these countries have already revised
or are revising their standards based on that research. Unfortunately no similar
anthropometric research has been done in India to establish needs of the present
population.

There are a number of studies on basic anthropometry of people with disabilities and of
the elderly. Most of these have relatively small sample sizes (under 100), which make it
difficult to generalize to a whole population for design purposes. Some have larger
samples, but are not from Indian populations. Still others have adequate sample sizes, but
have dimension lists that are focused on specific applications such as ergonomics for
workplace design, so the usefulness of the resulting data base in terms of designing
inclusive environments is restricted.

The range of wheelchairs in use in India includes tricyles and caster-carts which have
ingeniously been designed to resolve local cultural needs. A lack of anthropometric
study of these devices, despite their popularity, has led to poor representation of the needs
of their users in the present Indian accessibility standards and building codes. The review
of existing literature indicates that there has been no anthropometric research to verify the
effectiveness and validity of the Indian accessibility standards.

To date, the majority of wheelchair research stems from research groups based in western
countries and obviously is directed towards populations of users and wheelchairs in
predominantly western countries and their environment. As such, apart from the works of
Chakrabati, Mukherjee et al and Goswami et al, little research is available that addresses
specific non-western populations of users or wheelchairs. Owing to differences in
anthropometry among user populations and among populations of wheelchairs studied,
the application of anthropometrical data from wheelchair research originating from
studies in western countries will therefore be limited for the specific Indian
environmental context. This stresses at least part of the importance of the much needed
local anthropometric research in India.

Summary of Findings from Anthropometric Field Study
The data collected from the field study was compared with the anthropometric
recommendations in the various Indian accessibility standards and guidelines. The
following tables compare this study with the Indian Standard IS 4963: Recommendations
for Buildings and Facilities for the Physically Handicapped (1987, Reaffirmed 1992),
Indian Standard IS 7454: Rehabilitation Equipment - Wheelchairs, Folding, Adult Size –
Specification (1991, Reaffirmed 1997), Central Public Works Department (CPWD)
publication ‘Guidelines and Space Standards for Barrier Free Built Environment for
Disabled and Elderly Persons’ (1998) and the accessibility guidelines ‘Planning a Barrier
Free Environment’ published IN 2001 by the Office of Chief Commissioner for Persons
with Disabilities (CCD).

The last column in the following tables highlights significant difference between the data
collected during the field study and the Indian Standards IS 7454 and IS 4963. Although
the CPWD and CCD accessibility guidelines have been included in the comparative
tabulation but only the recommendations from the Standards have been used for purposes
of the last column.

a) Static Anthropometry
The following tabulated comparison indicates several significant differences between the
recommendations of the Indian standards and the anthropometric data collected from the
field study. Major variations were noted in the handle height, armrest height, seat height
and the combined knee and toe clearance recommendations.

Table: Summary of Findings: Static Anthropometry
Standard Field Study IS CPWD CCD Significant
7454 Difference
Min 5th 50th 95th Max
%ile %ile %ile
Wheelchair Dimensions
Unoccupied 575 592 642 670 670 650 – 750 680
width 720
Unoccupied 925 935 1027 1139 1160 1000– 1050 1200
length 1100
Handle 885 888 918 974 985 910– X 920 *
height 950
Armrest 690 700 728 759 770 700 – X 760 *
height 740
Seat height 495 495 539 591 605 480 – X 480 – *
510 500
User Measurements
Occupied 645 666 734 828 860 X 800 900
width
Occupied 980 983 1112 1246 1260 X 1200 1150-
length 1250
Eye height 1030 1065 1141 1208 1240 X X 1100
–
1300
Total seated 1155 1186 1249 1310 1310 X X X
height
Knee height 570 573 654 718 725 X X 675
Toe height 180 190 239 301 305 X X 200
Combined 265 279 359 448 455 400 – 350 480 *
knee + toe 450
depth

b) Functional Anthropometry
The most significant differences between the recommendations in the Standards and the
data collected from the field study were in the ‘High Reach’ ranges, in both the categories
i.e. forward and sideways, and also the 360 degree maneuvering clearances.
Table: Summary of Findings: Functional Anthropometry
Standard Field Study IS CPWD CCD Significant
4963 Difference
Min 5th 50th 95th Max
%ile %ile %ile
Reach Ranges - Forward
High 830 886 1158 1449 1470 1350- 1200 1200 *
1600
Low 290 297 427 574 595 X 400 400
Obstructed 865 886 1111 1352 1380 715 – 1100 1100
high 830
Reach Ranges – Lateral
High 920 1126 1331 1496 1510 1350 1300 1300 *
–
1770
Low 230 233 289 329 375 X 250 250
Obstructed 860 898 1086 1237 1290 X 1200 1200
high
Maneuvering Clearances
Width – 770 787 950 1134 1155 X X X
90◦ L-turn
Circular 1400 1431 1643 1874 1930 1500 1500 – 1800 *
diameter – 2000
360◦ turn

Conclusions

a) Summary of Key Issues
The key issues that affect the anthropometry and access needs of Indians with disabilities
as identified by this research are as follows:-
1. None of the standards and guidelines is based on any original anthropometric
research done on the local Indian population of people with disabilities.
2. There is no database on functional anthropometry of the elderly Indian
population.
3. The structural anthropometric data on wheelchair dimensions in the Indian
accessibility standard IS 4963 does not include anthropometry of contemporary
wheeled mobility devices such as tricycles and caster-carts.
4. The standards do not provide minimum guidelines and requirements on several
essential dimensional variables such as occupied device dimensions, eye height,
90 degree turn width, knee and toe heights and clearance depths, low reach
ranges, etc.
5. None of the Indian standards correlate strength with anthropometrics.
6. No validation study has ever been done to check efficacy of the Indian standards.
7. There is poor documentation of the research methodology and sample population
studied in the standards and guidelines.
8. Most of the anthropometric design recommendations in the standards have
remained unchanged since the first publication.
9. Research results from the field study clearly indicate a variation in anthropometry
of wheelchair users from that described in the standards. The deviation is
significant in certain variables such as the knee and toe clearance dimensions, seat
heights, armrest heights, high reach ranges and 360 degree circular turning
diameters.
10. The dimensional data has only been presented as an absolute value, occasionally
as a range where only the maximum and the minimum values have been specified.
Also, none of the dimensional recommendations have been stratified by the
gender type.
11. Anthropometric dimensional data are included in the main document of the
standards.
12. Previous studies have only focussed on conventional anthropometry and no
attempt has been made to collate a 3-dimensional database to develop computer
human modeling techniques.

b) Implication of Results
An anthropometric database of disabled and elderly population is vital for designing
inclusive environments. The present knowledgebase of anthropometry of disabled
Indians, as reflected in the standards and guidelines, lacks data on several essential
dimensional variables such as occupied device dimensions, eye height, 90 degree turn
width, knee and toe heights and clearance depths, low reach ranges, etc. Moreover, there
is no database on anthropometry of the elderly Indian population. Also, the exclusion of
anthropometry of contemporary rural mobility devices such as caster-carts and tricycles
from the standards has not helped in encouraging accessibility in the built environment
for the users of these devices.

There is poor documentation of definitions of the landmarks and dimensions used in the
standards and guidelines. Additionally, there is no mention of the measurement methods
used, characteristics of the study population or the sampling techniques employed in the
research. A detailed description of the research methodology used and sample population
studied enables pooling of data across future studies and also helps in establishing
reliability and validity of the study.

Strength is a key variable in the ability to complete different functions and should be a
significant consideration in functional anthropometry. Unfortunately, Indian standards do
not correlate strength with anthropometrics and this severely limits designing of hardware
that is easily operable by people with disabilities.

There has been no validation study to check the efficacy of the Indian standards and
guidelines Moreover, most of the anthropometric design recommendations in the
standards have remained unchanged since the first publication. Population demographics
change over time from decade to decade and also the assistive technology keeps
evolving. It is, therefore, critical that updates and revisions be made to anthropometric
data tables periodically. In the absence of validation studies and any significant revision
to the standards it is unlikely that the design recommendations in the standards will meet
the needs of the present population.

Including anthropometric dimensional data in the main document of the standards makes
it very difficult to revise the dimensional recommendations on a regular basis as doing so
requires changing the main document of the standards. This may possibly be one of the
factors why the much needed changes in anthropometry have not been reflected in the
standards.

The research results from the field study clearly indicate that the dimensions of a standard
wheelchair and the functional anthropometry of wheelchair users vary from those
described in the standards. This reveals that the design needs of the present population of
wheelchair users are not adequately reflected in the regulatory standards and, therefore, a
significant proportion of disabled Indians are likely to find the built environment
inaccessible.

All the Indian standards and guidelines lack in providing the data in a format that may be
useful for designers and policy makers. The dimensional data has only been presented as
an absolute value, occasionally as a range where only the maximum and the minimum
values have been specified. Moreover, although it is well known that anthropometry
varies with gender, none of the dimensional recommendations have been stratified by the
gender type. The designers and policy makers need to know the 5th and the 95th percentile
values as also the mean and the mode values to enable them to cater to specialist
populations such as when designing a rehabilitation centre or an aisle chair for use by
disabled people in airplanes.

c) Recommendations
Guidelines and standards for accessible design are based on data derived from
anthropometric research of people with disabilities. This research indicates that the
available regulatory and guidance documents in India do not represent needs of the
present range of wheeled mobility users. Changes in codes and standards are needed to
truly reflect the needs of the local Indian population.

Studies of anthropometric needs of wheeled mobility users in rural areas are important
and remain to be undertaken as differences in cultural and economic prerequisites must
be taken into consideration when representing the access needs of an entire country in the
national standards. It is important to study the anthropometrics of tricycles, caster-carts
and other contemporary wheeled mobility devices so that the needs of their users may be
incorporated in the standards so as to address the reality of local contemporary wheeled
mobility use.
Results from the field study suggest that the clear floor areas and seat heights be
increased in the standards to address the actual size of wheelchairs in use. Also radical
changes are indicated in the knee and toe clearance dimensions, seat heights, armrest
heights, high reach ranges and 360 degree circular turning diameters

To provide a realistic guidance for designers, information on wheelchair accessibility
dimensions should include occupied sizes as well and also include more information on
the structural anthropometry of the users. Occupied sizes and user dimensions are most
valuable for designers for establishing clear floor area and other space requirements than
the unoccupied wheelchair dimensions but the existing standards and guidelines only
provide very limited information on these. Other dimensional variables that specifically
need to be added to the standards include eye height, 90 degree turn width, low reach
ranges, knee and toe heights and clearance depths. There is also a need for studying
strength, in its various dimensions and the need to study the correlation between strength
and anthropometrics in the accomplishment of activities of daily living in order to design
enabling environmental hardware.

The anthropometric specifications and dimensional recommendations should be included
either in a supplementary document which is not part of the standards or be included in
an appendix to the main document. This is crucial as later revisions in the anthropometric
recommendations, which will be essential as our understanding of the anthropometrics of
disability increases and also as the assistive technology advances, may be incorporated
easily without needing to change the main standards.

The importance of the much needed local anthropometric research in India can not be
over-emphasised. A major nationwide anthropometric survey is recommended to provide
specific anthropometric data on the general Indian population of people with disabilities
and the elderly across urban and rural India. This will provide the groundwork to support
improvements in the accessibility guidelines and standards so that they more accurately
reflect the functional abilities and needs of the local Indian population of people with
disabilities.

Anthropometric studies conducted today will need to address the design challenges of
tomorrow and therefore it is essential that anthropometric research is undertaken
periodically to review the standards as the assistive technology keeps evolving and the
demographics of disability keep changing.

Limitations of the Study
The sample described in this study was not representative of the Indian wheelchair
population in terms of gender, ethnic diversity, wheelchair type and disability type. The
field study only included anthropometric research on manual wheelchair users who have
been disabled due to spinal cord injury and, therefore, may not necessarily represent the
needs of all wheelchair users. Moreover, since the study was conducted in New Delhi, it
does not have representation from other geographic areas whereas it is well established
that people in the Southern and Eastern states of India have significant anthropometric