Workshop Accessibility and Research Atlanta, Georgia, USA
October 26, 1993
Submission to the first North American Regional Conference of Rehabilitation International
ACCESSIBILITY AND KNOWLEDGE:
CONNECTION BETWEEN RESEARCH, DESIGN GUIDELINES AND STANDARDS Progress in the Netherland
Theo J.M. van der Voordt
OSPA Research Institute of Urban Planning and Architecture Delft University of Technology, Department of Architecture
Delft, the Netherlands
Summary
Much knowledge is acquired by trial and error. Scientific research can help to acquire this in a methodical manner. The dissemination of information takes place in different ways too, by means of lectures, video presentations, books and articles. Design guidelines and standards can be helpful in enforcing the application of knowledge. However, dissemination of information and
standardisation are in themselves insufficient. Prerequisites for the widespread application of knowledge are a clear and attractive presentation, certitude about the correctness of the information and consensus over the objectives. For designers, another important issue is freedom of choice. Information and standardisation should not stand in the way of innovative solutions. In this paper, a brief review will be given of the history of the development and dissemination of information on accessible environments in the Netherlands. Furthermore, some recommendations will be discussed for an international research agenda.
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1. Introduction
As in many countries, the accessibility of the built environment for people with a disability did not receive serious attention in the Netherlands until the early sixties. People with a disability were left entirely to their own devices until well into the nineteenth century. Only in the second half of last century was any form of medical care or schooling provided for sensory disabled people. In the course of the twentieth century medical care, rehabilitation and teaching provisions have been vastly extended and financial assistance introduced. In the realm of architecture, however, designers and developers continued until relatively recently to cater exclusively for people of average height, strength, stamina, and competence, with little regard for preventing the dysfunction of those who failed to match this profile. It is only in recent decades that any true concern has been shown for the special needs of disabled people in relation to the built environment. This is largely due to the influence handicap organisations have brought to bear on policy and those involved with building the environment. For example, the first publication on `Housing the Disabled' (Woningen voor Minder Validen) was brought out in 1960 by the Netherlands Association for Care of the Disabled
(Nederlandse Vereniging voor Gebrekkigenzorg). Fortunately, much has improved since 1960. In this paper, I wish to sketch a bird's-eye-view of the main developments during this period and the role of design guidelines, standards and research in this process.
2. From Research on Accessibility to Universal Design
Designing means devising solutions, weighing one variant against another, and taking decisions. This requires experience, intuition and creativity. Equally important, however, is clarity over the pursued goals and an understanding of the consequences of the design options in relation to use and appreciation. Research can help clarify and substantiate goals as well as provide an insight into the efficacy of the deployable means. Ideally, design and research should be closely linked in an interactive and cyclic process in which the design process generates questions and hypotheses, and research explores knowledge and tests hypotheses. On the basis of this data, existing design solutions are rejected or adjusted and new solutions developed, which are in turn evaluated and tested. In practice, the relationship between design and research is less close. Interaction is marred by lack of consensus, conflicting interests and limited financial resources. A great deal of time and energy is needed to achieve widespread recognition for problems and to come up with better design solutions. A good example is the practicality of the built environment for people with a physical disability. This was the result of a lengthy and intricate cooperative effort (fraught with frequent resistance) on the part of a few forerunners, handicap organisations, government authorities, designers, researchers and health-care workers. I want to illustrate this with a review of the main developments in the housing and public services sector.
Housing: From Unadapted to Adaptable Dwellings
As already mentioned, the first publication on housing the disabled appeared in 1960. Based on a small study with two wheelchair users and several walking stick users, it published a list of the requirements that a dwelling needed to comply with to be suitable for people in these disability groups. At that time, the only adaptations for disabled people were those individually tailored to the occupant's needs after moving into the dwelling. This posed serious problems for people who were severely disabled. This and the absence of professional domiciliary care meant they were rarely able to live on their own. When parents were unable or could no longer look after them, institutional care was the only alternative. These institutions were generally situated in a woodland area outside the `normal' community.
3 The year 1962 saw the completion of the first two dwellings which were adapted for wheelchair users during construction. The project was the initiative of a doctor active in rehabilitation. Based on the recommendations of the 1960 report, he succeeded in restructuring the ongoing construction of three council houses into two adapted homes for families of which the housewives used a
wheelchair. During this same period `The Village' (Het Dorp) was built, financed mainly with private and corporate donations in response to a well-publicised campaign. The project consisted of 400 independent housing units for disabled people with round-the-clock support available with activities of daily living (see also Guffens, 1992). Once again, the initiative came from a doctor concerned with improving the living conditions of disabled people.
In 1970, the government installed an Interministerial Steering Committee on Policy for the Disabled. A study published by the committee (1976) discriminates three adapted dwelling types:
- type A, consisting of a number of independent living units with limited service provision (hot meals, home nursing, light personal care), interspersed (provided they are easy to reach) or clustered among standard housing;
- type B, a small home or hostel accommodating twenty-five to thirty people offering a more extensive package of services than the A-type dwelling, including support with social and cultural activities;
- type C, consisting of independent units forming part of a larger community complex (two to four hundred people) and an extensive service mix including medical assistance and support in relation to the basic living activities.
People with a limited disability who are able with some help to look after themselves qualify for the A-type dwellings. The B type is meant for people who are more severely disabled and unable or unwilling to live on their own. For those with a severe disability and limited mobility and range of activity in relation to daytime activities and social contact the C-type dwelling was felt by the committee to be more suitable.
As far as is known, some forty B-type and four C-type projects have been realised in the Netherlands to date. The concept of type C is out of date now; in some of the existing examples the number of units has been reduced. An important milestone in independent living for people with a disability was the completion in 1978 of fifteen A-type Fokus dwellings and a service centre in the new town of Almere Haven as part of a social housing complex of 205 council homes. The name Fokus derives from the foundation of the same name, established by the Swedish doctor S.O. Brättgard in 1964. The foundation was set up for the purpose of realising accommodation for severely disabled people with round-the-clock support with day-to-day living activities. Meanwhile forty-two projects of this type have been realised in the Netherlands, accommodating some 550 disabled people. Each project consists of a maximum of fifteen specially adapted rented dwellings integrated in the community. Besides being based on a literature study, the architectural formula of the Fokus dwellings is inspired by research Brättgard carried out in his capacity as professor at the Department of Handicap Research of Göteborg University. A number of experimental designs have also been tested by people with different disabilities.
A moot point in building dwellings for people with a disability is which adjustments should be incorporated at the design phase and which are better left until later when they can be tailored to the occupant's individual needs. Since the Fokus dwellings are allocated at an early stage and virtually all the occupants are wheelchair users, the wheelchair adjustments are incorporated as standard features of the design. Usually a number of customized adaptations are made on top of this.
4 In a report published in 1974 containing design recommendations for dwellings for wheelchair users, the author (another doctor) argues in favour of one to one-and-a-half per cent of all new housing being purpose-built for wheelchair users. Various municipalities adopted this recommendation. In practice, however, the strategy proved problematical, particularly with regard to the fine-tuning of supply and demand in terms of both quantity and quality. Like everyone else, disabled people have different preferences in housing depending on the composition of the household, income and lifestyle. This has resulted in long waiting lists for some wheelchair dwellings while others have been left vacant. After carrying out an extensive investigation in 1984, the government decided to abandon the policy of building a specialist housing stock.
An entirely different approach is `Adaptable Housing'; new build or refurbished housing which is not purpose-built or specially adapted for disabled people but which is designed in such a way that adaptations can be made relatively simply and cheaply at a later stage if the occupant becomes disabled or a disabled person wishes to move into the dwelling. This concept was championed in the early eighties by the architect Job Kroon. Initially his ideas met with much scepticism: they were considered too complicated and too costly. He endeavoured to convince his critics of the technical and economic feasibility by applying the principle in his own architectural practice and conducting a modest study into the cost-effectiveness. In the mid-eighties, the National Housing Council (Nationale Woningraad), an umbrella organisation of housing corporations, instigated a large-scale experiment in `Adaptable Housing'. In the theoretical phase, a list of `Requirements for Adaptable Housing' was drawn up based on the results of a literature study and interviews with disabled people and handicap organisations. Forty projects implementing these requirements were then realised, providing for a total of some twelve hundred dwellings. Parallel to this experiment, Delft University of Technology calculated whether implementation of the adaptable housing requirements
necessitated building larger dwellings compared with other standard systems. The results were by and large favourable and would seem to indicate that adaptable housing is feasible in many cases (for a more extensive discussion see Van der Voordt, 1990/1992). Meanwhile, the National Housing Council, in conjunction with Delft University of Technology and other organisations, launched a follow-up project, this time for `Adaptable Refurbishment'. The theoretical phase has since been concluded, resulting in a check list of adaptability requirements and a phased refurbishment plan (Nolte et al., 1993).
Public Provisions: Towards an Integrated Approach
In addition to the studies on accessible housing, considerable research has been carried out into other areas directly or indirectly affecting the general accessibility of the environment. Table 1 specifies the items examined. The research methods employed vary from written questionnaires and interviews to laboratory research into the space requirements in field tests reproducing the actual dimensions, and from desk research into the costs of accessibility provisions in public buildings to practical experiments with acoustic signals for traffic lights on the public highway. The scale of the research varied considerably, too, from experiments involving a handful of test subjects to
large-scale questionnaires. Large-scale empirical studies on space requirements are rare. As far as is known, only two such studies have been conducted in the Netherlands, one into the use of ramps and the second into the space needed for opening and shutting doors. In both cases the research was carried out by the special `Universal Building' working party at Delft University of Technology. Another relatively large research project evaluated users' experience of a specially adapted route in Gouda, a fairly large town in the west of the Netherlands. As well as reviewing the provisions for wheelchair users, the study evaluated a footpath for visually impaired people. For this, a fairly long 60-centimetre-wide path in Gouda town centre was surfaced in a distinctive material (ribbed paving).
5 The study revealed that while helpful to the nearly-blind, the path was less suitable for blind people, who often wandered off it. Blind people expressed a clear preference for a guide line along the facades of buildings, without interruptions or obstacles such as parked bicycles and displays of goods outside shops on the pavement.
Table 1: Aspects of accessibility currently being studied in the Netherlands
* Number of disabled people, total as well as in each category * Anthropometric data on elderly and disabled people
* Needs of disabled people, including mobility needs, priorities of accessibility of facilities * Actual obstacles encountered by disabled people, differentiated according to type of disability * Accessibility and inaccessibility of specific buildings and outdoor spaces
* Accessibility criteria with respect to functional principles and space requirements * Criteria for adaptability
* Frequent individual adaptations * Alternative transport provisions
* Evaluation of the use of existing solutions
* Product development (ergonomic wash basin, suspended lift)
Striking is the tendency seen in more recent publications towards the integrated approach. Instead of individual adaptations or categorial provisions such as special ramps for wheelchair users, there is an increasing tendency to seek solutions which are acceptable to everyone, such as an entrance with automatic doors and no threshold. In a recent study for the Ministry of Housing and
Construction integrated accessibility was defined as `that which can be used readily and - as far as possible - unassisted by everyone alike' (Wijk, 1992). `Everyone' is understood to mean `every person, with or without personal aids or belongings (wheelchair, crutch, luggage, pram) who is represented by the broad average. The latter encompasses that group of people implicitly represented by a system of measurement based on the principle that people differ in size and physical ability. For instance, if the clear width of a doorway was set at 850 mm, everyone who could pass through this would fall under the broad average for purposes of this activity. People in too wide a wheelchair or with too wide a pram would by definition not qualify. Within the frame of an European Manual for an Accessible Built Environment, a group of experts is currently engaged on formulating standard international measurements (CCPT, 1990).
3. Communicating Information: Dissemination and Standardisation
In order to ensure that knowledge gleaned from research and practical experiments finds its way to designers' drawing boards and policy-makers' desks -it has to be presented in a form accessible to them. Lectures, reports of research and scientific articles are in themselves insufficient. Considerable attention is paid in the Netherlands to the dissemination of information in an accessible form, such as educational films, manuals aimed at a wide audience and checklists with points for attention and suggestions for consideration during the design phase. An important publication in this respect is `Geboden Toegang' (Call for Admittance), issued by the Dutch Council for the Disabled
6 The first version of this manual for the design and construction of practicable and accessible buildings for disabled people appeared in 1973. The information was based on existing literature and practical experience of specialists, supplemented by small-scale studies on space requirements at a
rehabilitation centre. The eleventh edition of this work was recently brought out. Originally, the manual consisted primarily of standard solutions for interior spaces such as the entrances to dwellings and public buildings, living rooms, bedrooms, toilets, and solutions for moving between levels (stairs, lifts, ramps) both indoors and outdoors. Also it was initially concerned primarily with people with a motor impairment, in particular wheelchair users. The reasons for a given solution were not always clear. This meant that designers had insufficient information with which to generate their own design solutions and test the workability of these. Later versions devoted more attention to the functional principles underpinning designing an accessible environment. Furthermore, it has since been expanded with information on the accessibility requirements of sensory disabled people. In the meantime the manual `Geboden Toegang' has become a household word in the Netherlands and is cited regularly by developers and designers, and those responsible for assessing plans and compiling legislation. Despite its merits, in practice there was a need for information on specific building categories. To this end a so-called `Prototype Guide for Accessibility' founded on the `Geboden Toegang' manual was developed (CCPT, 1984). And on the basis of this, guidelines were then drawn up for office buildings, shop amenities, health care buildings and recreational facilities. As for traffic measures for people with a disability, the Ministry of Transport and Public Works published a separate manual. Similarly, the findings of the pilot project `Adaptable Housing' were recorded in a separate manual in the form of guidelines for designers and appraisals of practical examples (Nationale Woningraad, 1992).
Information on its own is not enough. A certain amount of force is needed to ensure that planning takes account of accessibility at all levels including those relating to disabled people. In 1987 the Union of Netherlands Municipalities (Vereniging van Nederlandse Gemeenten) incorporated a selection of accessibility requirements in its so-called `Model Building Regulations'. Until the end of 1992, this formed a basis for the building regulations that the local councils were obliged to draw up for their own municipality. Under the current policy of deregulation, which seeks to reduce
government prescription and to increase the individual responsibility of the relevant parties, the municipal building regulations have since been abolished and replaced by a Building Decree (Bouwbesluit) which is valid nationwide. This stipulates a limited number of requirements pertaining to the accessibility of public buildings and communal areas in residential buildings. There are virtually no regulations governing individual housing units.
In addition to the Building Decree, the Dutch Standards Institute's standard sheet no. NEN 1814 of 1989 wields a certain amount of influence. This standard sheet, which concerns the accessibility of buildings and outdoor spaces, was compiled by a committee of experts whose members include designers, researchers and representatives of handicap organisations. The present standard is mainly based ont the guidelines in Call for Admittance. No specific additional research has been done. Although not legally binding, the standard sheets published by the Dutch Standards Institute are frequently taken as a guideline in Dutch building practice.
4. Recent Research on Accessibility
A new edition of the manual `Geboden Toegang' appeared at the end of 1994. The revised edition gives greater prominence to the integrated approach. It also incorporates the findings of adaptable housing and takes account of technological innovations and current research into the possible applications of what is known as a `suspended lift' (a new type of stair lift).
7 In order to ascertain whether further empirical research on space requirements is desirable before rewriting Call for Admittance, Delft University of Technology and the National Housing Council have recently taken stock of the research carried out to date (Van der Voordt et al., 1993). Altogether, a total of forty studies were traced (see the appendix). Many of these could not be used or were no longer valid. Some of the research material had dated. Other studies were rejected on the grounds that the number of test subjects was too small or because the findings were written up in languages that could not be read (e.g., Finnish or Swedish), or because it was impossible to obtain the report of the research in its original form. After weighing all these considerations, nineteen publications were finally selected for further analysis.
Concomitantly, various movement studies were made of the space requirements of wheelchair users. These movement studies examined:
- the sub-activities of which an activity was built up;
- in which sequence the sub-activities were or could be carried out; - the amount of space required for each sub-activity; and
- the amount of space required when the sub-activities were performed as an integrated activity. The use of the toilet is an example of such an activity. This activity can be broken down into five sub-activities: opening and closing the door, using the toilet, washing one's hands, and leaving the room. The activities with spatial consequences are positioning the chair diagonally in front of the toilet, standing up and turning, and seating oneself on the toilet. The space required for this is calculated by making scale drawings of these movements with the help a computer. For the present, the movement studies are confined to use of the toilet, shower and wash basin, vertical transport by means of lifts, and the opening, passing and closing of doors.
Although the list of empirical studies on space requirements is probably not exhaustive, it would seem safe to conclude that this type of research is comparatively sparse. Worldwide, only a scant number of studies were encountered with sufficient test subjects to draw reliable conclusions. Also, in most cases the basic assumptions are only briefly described so that no insight can be gathered into the effect of variables on the space requirement. This applies, for instance, to the different space requirements of people in different types of wheelchairs (hand-powered as opposed to electric, narrow or wide, large or small turning circle), or to the variation in space required by people with full use of one arm or hand as opposed to people with partial or complete loss of this function. What is more, no study provides sufficient data on the population to which the results relate. Because of this, it is impossible to extrapolate from this data what percentage of the population would fall outside the broad average if the recommended space requirements were to become standard.
Further, an analysis of empirical research findings reveals that dimensions vary considerably from source to source. Various studies on the use of doors (table 2) illustrate this. There is plainly little consensus over the room needed on the hinge side and lock side. For instance the space needed to open a door which is opening towards the user (A) and which is approached from the hinge side (1), the measures differ from 1200 x 2000 mm in a study of Brättgard (1974) to 1485 x 2220 mm which is recommended by the present Australian Standard (1993). The studies also differ greatly in depth. In several publications, for example, the space required for closing doors and the effect of the approach direction on the required space is hardly reviewed.
8 The most extensive information is given by the Australian standard: in addition to discriminating the direction of approach or turn, it also makes a distinction in its recommended measurements between the manoeuvre space required for a doorway with a clear width of 760 mm and one of
850 mm. Given the substantial measurements recommended, in practice it would seem advisable to install automatic doors in public buildings or do away with doors altogether when adapting individual dwellings.
Where no measurements are given, the same measurements apply as for opening the door. The variations in the recommended measurements can be partly attributed to the different basic assumptions on which the studies are founded. For example, it makes a great deal of difference whether a universal toilet is taken to mean a toilet which can be used by everyone including people who are wheelchair-bound and allows for various transfer techniques, or whether certain transfer techniques are not taken into account. Another explanation for the divergent results is the composition of the sample group. In some cases the sample is a random group from the disabled population. In other instances, all the test subjects are recruited from one rehabilitation centre or the most severely disabled test subjects serve as the yardstick. Lastly, cultural differences also appear to play a role. For instance, it is striking how greatly transfer techniques in the Netherlands and other countries differ (table 3). It is therefore urgently recommended in future studies to provide
background information and carefully describe and explain the basic assumptions when reporting on research.
5. Towards an International Research Agenda
This recent search for data on the space requirements for various categories of disabled people has revealed that there is still insufficient information available on the following items:
- space requirements for bedrooms and bathrooms, particularly when supports and/or hoisting equipment are needed;
- space requirements for exceptionally tall or short people;
- space requirements for people in electric wheelchairs which deviate from the models reviewed in most studies (e.g., scooters);
- space requirements for severely disabled people, for instance, people with no arm or hand function;
- incidence of the different transfer techniques and the workability of alternatives;
- the space required on the hinge side and lock side of a door and the space needed for opening and shutting doors;
- possible applications of technological innovations and the consequences of these for the measurements of buildings and outdoor spaces;
- experience of those living in adaptable dwellings.
Relevant non-metric research issues are for instance the use and useability of tactile warnings for people with sensory impairments international exchange of knowledge, guidelines and standards, and methods to convince and educate architects and design students.
According to a recent issue of Access America the American Architectural & Transportation Barriers Compliance Board has placed a number of these items on its research agenda. No doubt studies are currently in preparation or progress in other countries too. The dovetailing of all these research projects and possibly international negotiation of the division of labour is an appropriate task for the International Commission on Technology and Accessibility.
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APPENDIX: Emperical Studies of Space Requirements of Disabled People
(The analysed publications are marked in bold type)
Aiello, J. and E. Steinfeld (1978), Accessible Buildings for People with Severe Visual Impairments. U.S. Department of Housing and Urban Development, Washington D.C.
American Telephone and Telegraph Company (1975), Universal Public Telephone Height for Handicapped and Able-bodied Users. A Field Trial. Research Section and Marketing Department. Andren, E. and B. Petersson (1974), Space Requirements in Lavatories and Bathrooms for the Physically Disabled. Part 2 of Studies with Physically Disabled People as Test ubjects. Department of Handicap Research, University of Göteborg. [in Swedish].
Andrén, E., S.O. Brättgard, I. Lidberg and B. Petersson (1976), Ramper för rörelsehindrade. Department of Handicap Research, University of Göteborg.
AUBRCC (1977), Field Testing of Australian Standard 1428.1-1977. Sydney.
Blonk, C. (1991), Dan toch maar even tillen... Wageningen. ['Exploration of space requirements for the bathroom in a hostel for the mentally handicapped].
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Brättgard, S. (1976), Ramps for Disabled People. Department of Handicap Research, University of Göteborg.
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Cunniffe, P. (1971), A Report on the Optimum Height of Domestic Sockets. Institute for Consumer Ergonomics, Loughborough University of Technology.
Department of the Environment (1992), Sanitary Provision for People with Special Needs.
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Floyd, W.F. et al. (1966), A Study of the Space Requirements of Wheelchair Users, Paraplegia vol. 4 no. 1, pp 24-37.
11 Grefte, C.D.M. (1993), Passen en meten met de rolstoel. Landbouwuniversiteit Wageningen. ['Research on space requirements of wheelchair users for the bathroom'].
Harris, C. et al. (1985), Isometric Torques Applied to Lever Door handles by Disabled and Elderly People. Loughborough University of Technology.
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