8 Factors to consider
8.1 General
8.1.1 This clause, to be used in conjunction with Tables 1 to 7 and the fuller descriptions of abilities in clause 9, provides more detail on the features of products, services and environment that assist or hinder older persons and persons with disabilities.
8.1.2 Clauses 8.2 onwards expand on the key words used in the Tables, describing the factors to consider to make products and services accessible. Examples of possible solutions are given but these should be treated as guidance and not specifications. The list of problems and solutions is not exhaustive.
8.1.3 Where they exist, International or National Standards on accessibility should be consulted before writing new or revised standards that meet any of the table positions identified as a result of 7.3.3.
8.2 Alternative format
8.2.1 General considerations
An alternative format (defined in 3.8) describes a different presentation or representation intended to make products and services accessible through a different modality or sensory ability. By providing all input and all output, i.e. information and functions, in at least one alternative format, for instance visual and tactile, more people, including some with language/literacy problems, may be helped. In terms of function for people with dexterity and strength impairment, alternative packaging solutions may need to be envisaged.
8.2.2 Alternatives to visual information
The type and texture of surface finishes can be important in providing tactile feedback which can reinforce instructions and warnings for those with visual impairment. Where the principal form of instruction on a product or in a building is written, alternatives would be voice (instructions 'spoken' by a product or service), sound (feedback from clicks, bells and buzzers) or touch (tactile marking or grip).Wherever feasible, visual information which is presented on electronic products should be available from the product in audio or other sensory stimuli for those with a visual impairment including those who cannot read braille, as well as for those who have difficulty with reading or are unable to read. Printed visual information should be available in alternative formats (electronic audio, large raised letters or braille, etc.) which are readable by individuals without vision and in large print for those with low vision.
8.2.3 Alternatives to auditory information
Wherever feasible, sound signals should be supported by visual or other sensory stimuli for those with a hearing impairment (e.g. communication in writing, graphical symbols, vibration or sign language). In particular, audible warnings, such as fire alarms, should also activate, for example, visual stimuli, such as flashing lights which are well sited and clearly indicated.
8.2.4 Alternatives to voice input
Where voice input is used to activate a process, for example building entry security systems, alternatives such as keypads or the use of video monitoring should be considered.
8.2.5 Biological identification and operation
Where biometric forms of identification are intended, an alternative form of identification or activation should also be provided. For example, if systems require a retinal scan and a person does not have a retina, or the system requires a fingerprint amd the person does not have hands or uses a prosthesis, such people are unable to operate the devices unless some alternative form of identification is substituted.
8.2.6 Prevention of seizures
Flicker rates, or flashing or blinking text, objects or video screens should avoid frequencies that are most likely to trigger visually induced seizures.
8.3 Location and layout of information and controls and positioning of handles
8.3.1 Location
The position of information and controls on a product, or in a building, or even the point at which information is available for a service (e.g. warnings about the terms on which dry-cleaners accept clothes for processing) are important. They need to be prominent for someone with a visual impairment or language/literacy disability, visible from the angle of view of someone standing and seated in a wheelchair, and easily accessed by seated or standing users without bending and stretching. This may mean that the positioning needs to be flexible or adjustable or duplicated. Information or controls should be located in a position where they will not be obstructed, for example when a product is held by either or both hands, or held in a different way by someone with manipulation or strength impairment.
8.3.2 Buildings
The design of buildings can incorporate simple measures that enable people to feel more confident in the physical environment, such as well placed, sturdy handrails. Controls and door handles within easy reach facilitate use by those with impairment in dexterity, manipulation, movement or strength.
8.3.3 Layout
The layoutof information and controls will also determine how easy they are to read by someone with a visual or cognitive impairment. Factors to consider include logical grouping of information and controls, line length of text, relevance of information and relationship of controls to actions to be undertaken.
8.4 Lighting levels and glare
8.4.1 Provision of lighting
Appropriate lighting ensure that those with a visual impairment are better able to see instructions and controls. This should also be considered for those with a hearing impairment to assist with lip reading or sign language communication.
8.4.2 Consideration of ambient lighting
The likely lighting levels in typical use should be considered, for example television controls may be operated in a darkened room, installation of a product may be in a dark space.
8.4.3 Buildings
Adjustability of lighting levels in a building is desirable to suit different needs but sudden changes in lighting levels should be avoided.
8.4.4 Avoidance of glare
Too high light levels and strong directional light can result in deep shadows or glare. Reflecting surfaces on information panels and glossy paper in instruction books or on packaging containing warnings should be avoided, to reduce the possibility of glare.
8.5 Clour and contrast
8.5.1 Choice of colour
This is important for ease of recognition and ease of seeing. Some colour combinations are also more effective. For example some colours, such as red/green, are not distinguishable by a significant minority of the population (those with colour blindness).
8.5.2 Colour combinations
The best colour combinations depend on the purpose of information, whether it is for guidance or a hazard warning, and the lighting conditions under which it is most likely to be viewed. For example, black on yellow or light grey are general purpose combinations which provide strong definition without too much glare, pastel shades on pastel backgrounds or red lettering or symbols on light grey are difficult to see and should normally be avoided.
8.5.3 Colour coding of information
All information conveyed with colour should also be available without the perception of colour. Colour coding should not be used as the only means for conveying information, indicating a response or distinguishing a visual element.
8.6 Size and style of font and symbols in information, warnings and labelling of controls
The required size of font for information, warnings and labelling of controls, relates to the probable viewing distance, level of illumination and colour contrast of the text against its background. The choice of font, whether with or without serif, in upright form or italics and light, medium or bold appearance also has a significant impact on legibility. Standards developers should also be aware that text writen in CAPITAL letters is more difficult to read. This is significant for those with a visual impairment. Consideration should be given to specifying size and style of font and symbols for warnings.8.7 Clear language in written or spoken information
8.7.1 Information available as text
Information should be made available in text format wherever possible, in addition to other forms, to facilitate recognition and translation into speech and other languages for those who have trouble seeing, recognizing or deciphering non-text information presentations.
8.7.2 Complexity of information
Instructions or operations which are too complex will often deter older persons and persons with limited intellect from using a product or device. Simple written or spoken messages are also clearer to understand by someone with a visual or hearing impairment.
8.7.3 Printed instructions
These should use short sentences of simple, straightforward and non-technical language and may include simple illustrations.
8.7.4 Spoken information
Rules for spoken information are similar to those for printed information. The context should always be given to ensure that information is meaningful and instructions should be provided in a logical order. Key points should be reinforced by repetition. People with hearing loss are at an increased risk or disadvantage if spoken announcements are not loud enough, or if the pitch is too high or too low.
8.7.5 Multiple languages
Where instructions are to be provided in more than one language, written information in each language should be presented in separate sections of a manual rather than interleaved on a page; spoken information should be preceded by a clear statement in the language to be used.
8.8 Graphical symbols and illustrations
The use of meaningful graphical symbols or illustrations, in addition to text, should be considered in instructions and also on a product, for ease of assembly or use. For example the same symbol should be used on the respective ends of parts to be joined, when assembling a product, or in the labels on controls.
8.9 Loudness and pitch of non-spoken communication
People with a hearing loss are at increased risk or are disadvantaged if warnings are not loud enough, or if the pitch is too high or too low. Where possible, volume should be adjustable over a wide range. Information should also be presented in multiple frequencies where possible (e.g. an alarm signal could consist of a strong component at multiple frequencies). Sudden changes in volume should also be avoided.
8.10 Slow pace of information presentation
Announcements spoken at a slow measured pace allow listeners to pick out the message; pauses between instructions give time to understand and act on the information. If a message is delivered too rapidly, it is difficult to assimilate by someone with a hearing or vision impairment, or learning disability. Consideration should be given to the length of time information remains in view when presented on moving displays, or when information is temporarily displayed and then removed.8.11 Distinctive form of product, control or packaging
8.11.1 Identification by form
A distinctive form can make it easier for those with visual impairment and reduced touch sensitivity to identify a product, to interpret the parts of a product to be joined during assembly and to distinguish between different controls. A familiar form can also aid those with impaired cognitive ability.
8.11.2 Orientation of product or control
Where possible, the form of the product or control should also indicate the orientation of the product or control, so the top or bottom, front or back, can be easily located by someone with a visual impairment.
8.11.3 Tactile warnings
The use of universally recognized tactile warnings on the container or packaging enables identification of toxic or corrosive materials. Similarly, tactile warnings are normally required in buildings, such as at stair openings, on steps, on platforms and at dangerous storage areas.
8.12 Ease of handling
8.12.1 Size, shape and mass
These characteristics of a product will affect how easy it is to lift, hold and carry. Lifting and carrying is eased if articles are shaped to facilitate easy grasping, with either or both hands. Light, compact articles are generally preferable thus the density of manufacturing materials needs consideration. Provided safety is not compromised wherever possible, products should be capable of operation by only one hand, preferably either hand.
8.12.2 Instruction manuals and location of markings
The size, number of pages and weight of paper used in an instruction manual can affect the ease with which it is held and pages are turned, which will influence the extent it is used.
8.12.3 Controls
8.12.3.1 Handling
The force required to twist, turn, push or pull controls or fastenings is significant for people with various impairments. Operating controls should allow comfortable grip, avoid twisting of the wrist, avoid the need for simultaneous actions and offer minimal resistance. Textured surfaces, to increase friction, assist the application of force. Provision of alternative controls offering greater leverage or power-assistance should be considered. Pre-programmable operation and personal preferred settings can be effective, particularly for people with cognitive impairment.
8.12.3.2 Spacing
Controls should be spaced to avoid interference when another one is being operated.
8.12.3.3 Status
Multisensory feedback should be provided on the status of controls.
8.12.4 Containers and packaging
Containers should allow easy opening and closing by adopting appropriate shapes, sizes and surface finish. Packaging, such as some food wrappings which are difficult to open can result in injuries as users resort to sharp knives or other gadgets to attempt opening. Operating forces should be as low as reasonably attainable, compatible with security of contents.
8.12.5 Duration of actions
Products should not need a long handling time and unnecessary repetition of operations should be avoided.
8.12.6 Timed responses
Whenever possible, users should be able to control any limits on the amount of time available to them to read or respond.
8.12.7 Elements in building and the built enviroment
Elements and parts of buildings such as windows, doors, bathroom-elements, lifts/elevators, lobbies, intercom systems, etc., should be accessible and easy to handle. This concerns the application of force, positioning, logical structure and having enough space to move around when using assistive devices.The same applies to the built environment (for example, street furniture, pedestrian crossings, parking meters) and handling in public transport (doors, ticket machines, etc.).These aspects are particularly valuable for those with impairments in seeing, balance, dexterity, manipulation, movement, strength and cognitition. See also 8.3 and 8.16.
8.13 Expiration date marking
In order to reduce the risk of food poisoning, clear expiration date marking of food is important, as is the ability to interpret this. It is of particular value to those with an impairment in taste or smell.
8.14 Contents labelling and warning of allergens
8.14.1 Clear contents labelling is important, as is the ability to interpret this. Warning of potentially hazardous substances, such as chemicals, gases and smoke is of particular value for those with visual impairment or in taste or smell. Clear content labelling of products and packaging is important for individuals who suffer from food or contact allergies. Attention should be drawn to any change in composition of existing products.
8.14.2 Specific labels for "allergy-tested" products and packaging, as well as clear instructions for safe use or operation, are helpful.
8.15 Surface temperature
8.15.1 Surfaces which may be touched inadvertently during normal operation should not get excessively hot or cold. The choice of materials to be used, for example under cold conditions, and the use of appropriate insulating materials needs consideration.
8.15.2 Warnings of where temperatures may be excessively high or low for functional reasons are of particular benefit to those with limited sensitivity in their touch receptors. The format of the warnings should be accessible to people with visual or cognitive impairment.
8.16 Accessible routes
8.16.1 Changes of level
Accessibility in and around buildings can be improved by avoiding unnecessary changes in level at, for example, doorways and lift thresholds. Even very small changes of level, edges and protrusions can cause tripping. Where level changes cannot be avoided, they should be as low as possible, and clearly marked.
8.16.2 Lifts/elevators and ramps
Where there is a change of level, lifts/elevators and ramps should be provided. The slope of ramps should be appropriate in order to be safe and usable by persons using powered scooters, walking aids and wheelchairs. Lifts/elevators need to be of adequate size.
8.16.3 Stairs
Any stairs and steps should be designed to accommodate older persons and persons with disabilities by providing handrails of an appropriate diameter and height on both sides. Steps should be of a consistent rise and tread to accommodate the length of a human adult foot. Ends of flights of stairs should be marked by appropriate colour contrast.
8.16.4 Flooring
Flooring should be reasonably slip-resistant, firm and stable: see 8.18.3. Floor guidance for visually impaired people should be provided.
8.16.5 Swing, sliding or powered door-closing systems
These can knock people off balance and should incorporate appropriate safety mechanisms. Consider alternative controls such as (hands-free) automatic operation. The timing of any procedure or operation should allow more time for people who move slowly.
8.16.6 Seating
This should be provided at appropriate locations in a facility or environment to enable users to rest.
8.16.7 Coverage
Accessibility should be planned for all areas where people normally work or use the environment; it should be ensured that the accessible routes connect those areas by the shortest possible path. Care should be given to the inclusion of sanitary facilities within the accessible routes.
8.16.8 Route information
Guidance on accessible routes through a building is of particular value to those with a visual, movement or cognitive impairment.
8.16.9 Emergency routes
It is essential that emergency evacuation routes are obvious, intuitive and accessible to wheelchair users and others with a movement or visual impairment.
8.17 Logical process
8.17.1 Operations
These, such as the opening of packaging and assembling, installing or operating a product, should follow simple, straightforward and logical sequences. This assists persons with visual or cognitive impairment.
8.17.2 Feedback
Consideration should be given to the provision of appropriate feedback when each action in a sequence of actions is successfully completed.
8.17.3 Repeated actions
Within a task, repetition can be helpful because it makes learning easier. (This may conflict with the needs of someone with a strength impairment, see 8.12.5) Individuals with cognitive impairments can use most well designed controls and displays, but they take longer to learn to use them and need error protection.
8.18 Surface finish
8.18.1 Slip-resistance and texture
The surface finish of a product/material is important for people with limited dexterity. A non-slippery surface aids gripping and manipulating. The use of distinct textures can also help someone with a visual impairment to distinguish different parts of a product or to locate controls.
8.18.2 Sharp points
Surfaces should be free from sharp points and edges which are a potential hazard to anyone but are particularly so for someone with a visual or touch impairment.
8.18.3 Flooring
Floors should be slip-resistant to facilitate movement by those with a visual impairment, impaired balance and general difficulty in movement. Cushioned carpeting is not recommended as a springy surface does not offer a firm, stable foothold and deep-pile carpet causes resistance for those with a shuffling gait, risking a stumble. This type of carpet can also be a hazard for people using walking aids. A change of surface material can cause a danger and should be indicated.
8.19 Non-allergenic/toxic materials
Avoidance of toxic and allergenic materials is particularly important for people with impaired tasting or smelling ability and those with contact, food or respiratory allergies.Examples of everyday objects that contain nickel or chromium, which can create an allergic response, include doorknobs and window frames. People with visual impairment who rely on touch or tactile feel may be at risk if they come into contact with allergenic materials.
8.20 Acoustics
8.20.1 Acoustical design
Attention to accoustical design will ensure that the environment is suitable for good verbal communication with low background noise, low reverberation and high quality amplification as appropriate. People with visual or cognitive impairment rely to a greater extent on sound clues.
8.20.2 Amplification and adjustment
Building these into audio equipment widens the range of users who may be accommodated.
8.20.3 Communication systems
Even with a good accoustic environment, hearing-impaired people have difficulty in hearing at a distance from the source of the sound. The availability of communication systems such as induction loops, infrared and radio systems means that they should be included.
8.21 Fail-safe
Product or system design should ensure that even when incorrectly assembled or installed or there is mistaken use of controls, the product or system will fail in a safe manner without hazard to the user.
8.22 Ventilation
Ventilation systems should not cause or enhance respiratory allergies or irritation.8.23 Fire safety of materials
Consideration should be given to the fire-resistance qualities in products and buildings which are used by people with disabilities. Materials susceptible to ignition by a small source such as a cigarette, match or other small flame present a potential hazard if they continue to burn, producing toxic smoke or result in rapid growth of fire.People who cannot move quickly or who do not see well are in particular at greater risk.
|
|
Last updated: 20.11.2009 © Copyright reserved Website design: Digital Accessibility Team