Public Access Terminals
Swipe card readers
Because of the need to accurately control the way the card is swiped, elderly and disabled persons are likely to find these difficult to use.
A smart card is a credit card sized plastic card incorporating an integrated circuit. This circuit holds information that can be securely and accurately read by all sorts of terminals. Smart cards are able to carry larger amounts of information than magnetic stripe cards. Smart cards provide the opportunity to make machines much more 'user friendly' than they have ever been before. For disabled and elderly people, a smart card can carry information that tells a terminal to:
- allow the user more time. Many elderly people and those with a cognitive impairment do not like to be rushed or to think that they are likely to be 'timed out' by the machine, so it is necessary to allow for such people to use the terminal at their own pace
- simplify the choices such as issuing a pre-set amount of money
- larger characters for people with low vision
- audio output of non-confidential information. The coding of user requirements is specified in the European standard EN1332-4.
Contactless smart cards
A contactless card, working at a distance of up to 10 cm, will help those who have problems placing a card in a slot. This is of particular importance to wheelchair users, those with Parkinson's disease or arthritis, and people with a visual disability.
Blind persons, and many elderly persons, have problems in inserting the card in the correct orientation; this is a particular problem with cards which are not embossed. It is recommended that a 2 mm notch is incorporated in the trailing edge (according to EN 1332-2).
External features, labels and instructions
When a person has located a terminal they need to know what type of machine it is, what it will do and how they can interact with it. The initial instructions are usually in the form of labels and signs applied to the surface of the terminal casing or as messages on the screen.
Labels should be placed where they can be easily read. If labels are positioned near the keyboard it is important that the labels are not scuffed or worn away. If this is likely then the labels should be replaced periodically.
On outdoor terminals, Braille has limited value in cold weather since tactual sensitivity is dramatically reduced with decreasing temperature. The estimated number of Braille readers in Europe is less than 0.02% of the population; so although useful for some blind users, Braille is not a total solution for visually impaired users.
Any instructions applied to the surface of the terminal should be written in simple and clear language. Type sizes as small as 10 point are not legible for many people. It is recommended that type size of at least 16 point (4 mm cap height) be used for labels.
For many wheelchair users, such as those with arthritis, it is not just a problem of reaching the card reader, but still having any useful grip as the arm is raised above the horizontal. This is particularly acute for swipe card readers.
Modern wheelchairs and scooters no longer come in a standard height, so much of the previous recommendations are of dubious validity. Research is needed to find data for the height of the parts of the user interface which can be reached by 95% of users in wheelchairs.
For the naïve user, it is often far from obvious where to insert the card. A flashing light around the card entry slot has been found beneficial. For those with hand tremor, it is useful if the entrance to the card reader acts as a funnel to guide the card in correctly.
Screens and interaction
On most terminals the visual instructions on the screen are the main guide for the user. There are a large number of factors that determine whether reading the screen will be difficult or easy for disabled or elderly persons.
People who wear bifocals find it difficult to read the screen of most public access terminals, since the screen may not be at a suitable distance for the near or far segments of their spectacles. In addition many people leave their spectacles in the car or do not wear them in public. So the number of people who have problems in reading the screen is much more than the 1.5% of the population considered to be blind or to have low vision.
The most common forms of colour blindness are inherited and are associated with the inability to discriminate red and green wavelengths. Because these defects are inherited as recessive traits, the incidences are much higher in UK males (c. 8.0%), who possess a single X-chromosome, than in females (c. 0.5%), who possess two. Total colour blindness is extremely rare.
Sunlight can degrade the viewability of the display for all users. The screen should be shielded from direct or reflected sunlight or other bright light sources. The display should be viewable from the eye level of a person sitting in a wheelchair. People with low vision should not be prevented from getting their faces close to the screen.
The conflicting requirements of tall pedestrian users and short wheelchair users can lead to a significant group of users having parallax problems when lining up the function keys with the displayed option. Lines on the user-interface leading from the key to the surface of the display can alleviate this problem.
Ideally users, including foreign visitors, should be able to choose the language; frequently this is only viable if the instructions are displayed on the screen or given audibly. It would be preferable if the user's card stored their preferred language so that the terminal automatically switches to this as soon as the card is inserted.
Developments in infra-red and short-range radio interfaces links make it feasible for a disabled user to have a hand control unit with a remote link to the terminal. This would require all terminals to use the same interface protocol, and care would be needed to ensure confidentiality of sensitive information.
Few people are trained to use public terminals. It is therefore very important that the instructions for using the terminals are carefully designed, particularly for elderly and disabled users.
Concise and simple sentences
Sentences should be concise and simple in structure, and only natural vocabulary should be used. Informative messages which advise the user of the progress of the transaction and inform the user when or how to perform a step in the transaction, should be clear and to the point, and provide confirmation of task completion.
Message content should be chosen very carefully since a message that might be acceptable to the users for the first few times they hear it may become unacceptable when they hear it for the hundredth time.
To help a visually disabled person locate a jack socket there should be a raised ridge around the socket. A funnel into the centre of the socket will also help guide the plug into the socket.
On some terminals a 'beep' will sound when a key press has been registered. However, this does not help a visually disabled person know whether they have pressed the correct key; one solution is for coding on the user's card to request speech output of key pressed for non-confidential information.
It is recommended that new equipment should provide guidance in the form of audible instructions. Audio guidance can assist people with visual or cognitive impairments, as well as first time users. For example an audible message could be "Your card has been inserted upside down. Please remove your card, turn it over and insert it again."
Digitally stored speech can give very good audio quality, but it is effectively limited to pre-stored messages. Full vocabulary synthetic speech is often difficult to understand for naïve users, particularly if they have a hearing impairment.
Many users with impaired hearing, can only hear lower frequencies, so they can more easily hear a male voice than a female one.
Terminals can include a small television camera and microphone. Users can talk over a video link to a customer service assistant at a remote location. This human assistance can be very helpful to an elderly person having difficulty.
If audio output is used to provide private information to the user, then it should be through a telephone handset located at the terminal or through a headset connected through a standard mini jack to the terminal; however, it is essential that the position of the jack socket is standardised. If a handset is provided, inductive coupling and amplification should also be incorporated.
Non-confidential information can be output on a loudspeaker, but the volume should be a function of the ambient noise level.
A standard layout for keypads is essential for blind people. There are currently two common layouts for numeric keys; the telephone layout and the calculator layout. It is recommended that the telephone layout be used exclusively on public access terminals.
To help blind people, there should be a single raised dot on the number 5 key. This should be positioned so as not to reduce legibility..
Colour coded keys should be:
|Yellow:||Clear or Correct|
|Green:||Enter or Proceed|
All keys or buttons should be tactually discernible.
The arrangement of keys
Function keys should be clearly separated from the numeric keys.
When command keys are vertically arranged, 'cancel' should be the uppermost key and 'enter' the lowest.
When the command keys are horizontally arranged, 'cancel' should be located the furthest left, 'enter' the furthest right.
It is better to position the command keys to the right of the numeric keys. They are then less likely to be inadvertently touched when entering numerals.
Where command keys are positioned beneath the numerical keys they may be a problem to visually disabled persons because they are likely to be pressed accidentally when entering numbers.
Command keys should be as large as possible so that the words on them can be larger and thus easier to read.
Colour should not be the only distinguishing feature between keys, since red/green colour blindness is not uncommon; if possible, the keys should have different shapes and be marked with symbols. People with poor manual dexterity or a hand tremor benefit from key tops which are concave.
Sound Feedback in the form of sounds such as a 'beep' or 'click' when a key is pressed is helpful to many people.
Tactile indication can be provided by a gradual increase in the force, followed by a sharp decrease in the force required to actuate the key, and a subsequent increase in force beyond this point for cushioning.
Many elderly people and those with a cognitive impairment do not like to be rushed or to think that they are likely to be 'timed out' by the machine, so it is necessary to allow for such people to use the terminal at their own pace; this requirement could be stored on the user's card.
Speech input for commands is an option in some situations. If this is adopted then the user should have the choice of keyboard or speech input. It is likely that speech input would be preferred by people without hands and those with intellectual impairments, but the keyboard is easier for those with a speech impediment.
Problems with PINs
Personal identification numbers (PINs) are a particular problem for many dyslexic and intellectually impaired people. In Europe over 25 million people have dyslexia to the extent that they cannot reliably remember and use a four digit PIN, unless they can choose their own number. The main problem for people with an intellectual impairment is to keep the number secret. Therefore both groups would find it advantageous to have the option of using a biometric method for identification (eg. fingerprint).
With biometric methods of identification it is essential that users have a choice between the biometric method and some other method (eg. PIN); the reason being that for most biometric systems there is some group of disabled people who cannot use it (eg. fingerprint identification requires the user to have fingers).
The user's PIN should not be displayed, printed or broadcast by any means. However it would be useful to have both an audible feedback and a visual one (eg. an X or a tick on the screen) to show that a digit has been input. Many people with even slight memory problems find it difficult to remember and input their PIN quickly, so it would be helpful to allow a generous amount of time before they are timed out.
As touchscreens become more common it is essential that they are designed for ease of use by everyone, including disabled and elderly people.
It is possible to increase the size of the characters on the screen for individual customers who require this facility. This can be done by selecting this option from a menu or, preferably, by storing this information on the customer's card. With touchscreen systems, it could be arranged that holding one's finger in the bottom right corner for at least two seconds indicates that one would like larger characters on the screen. Large characters will be difficult to implement on small screens.
Ease of use
To help elderly people and those with hand tremors, key fields should be as large as possible and separated by a 'dead area'. There should be high contrast between touch areas, text and background colour.
Graphical symbols (such as icons) should be accompanied by text.
For blind users, it is possible to arrange that holding one's finger in a specified corner of the screen for at least two seconds or tapping twice in the corner, initiates speech output. Another method would be to store this requirement on the user's card.
Touchscreens can either be triggered by insertion or withdrawal of the fingertip. With the latter system, it is technically possible for the user to pass their fingertip over the screen and get speech output describing the active area they are touching at the time. Then the system is only triggered by withdrawing the fingertip from over an active area.
Information, which is sensitive and private to the cardholder, should not be visible to any other person; screen filters improve privacy but often at the expense of visual quality. However, the user may wish to display information with large character size, but they should be made aware of the privacy problem.
Retrieving money, cards and receipts
Retrieving items from a terminal can be very difficult for people with poor manual dexterity and persons with low vision. Often more time is needed, retrieval points need to be clearly indicated and within reach for wheelchair users.
Security at cash dispensers is a major concern for many elderly people, and is often given as a reason for not using such terminals. Therefore anything which improves the user's perception of safety is to be welcomed (eg. better illumination in the vicinity).
Persons with poor manual dexterity often find taking a card from a terminal and then taking the money difficult to do in the allowed time. Increasing the time for everybody, increases the security risk. However it would be possible to let users decide if they want more time than the norm and store this requirement on their card.
Many people with arthritis have difficulty in gripping and pulling the card from the reader, particularly when the arm is extended above the horizontal. The card should protrude at least 2 cm from the slot surround. It is recommended that the force necessary for the user to retrieve the card from the terminal should be not any greater than that needed to stop the card from falling out of the reader.
- Provide high contrast location signs.
- Provide at least 200 lux illumination on the interactive areas of the terminal.
- Ensure that wheelchair users can reach the terminal and have adequate space to turn in front of the terminal.
- Provide facilty for storing the user's preferred interface on the card (according to EN 1332-4).
- Provide an orientation notch in the card (according to EN 1332-2).
- Ensure that labels and instructions are unobstructed and in an appropriate typeface.
- Where possible, the interactive areas should be between 800mm and 1200mm above the floor so that they can be reached by most wheelchair users.
- Adhere to standard keypad layout.
- Provide training in the user of the terminal for new users.
- AS 3769 Automatic Teller Machines: User Access
- B480-02 (2002) Customer Service for People with Disabilities.
- B65.1.1-01 (2001) Barrier-free design for Automated Banking Machines.
- B651-95 (1995) Barrier-free design.
- BS 6571 (1999) Vehicle Parking Control Equipment. This relates to the distance off the ground and from the vehicle of the barrier controlled parking equipment.
- EG 201 472 (2000) Human Factors (HF); Usability evaluation for the design of telecommunication systems, services and terminals.
- EG 202 116 (2002) Human Factors (HF); Guidelines for ICT products and services: Design for all
- EN 726 Requirements for IC cards and terminals for telecommunications use.
- ETR 165 (1995) Recommendations for a tactile identifier on machine readable cards for telecommunications terminals.
- ETR 170 (1995) Human Factors (HF); Generic User control procedures for telecommunication terminals and services.
- ETR 334 (1996) The implications of ageing for the design of telephone terminals.
- ETS 138 (1998) Public terminals for the elderly.
- ISO 7165-5 Wheelchairs - Part 5 Determination of overall dimensions, mass and turning space
- TC TR 007 (1996) Human Factors (HF); User requirements of enhanced terminals for public use.
- Guidelines for Designers of Public Access Terminals
- Automatic Service Machines - In Our Way
- ITM accessibility checklist from US Department of Justice
- USA Voting System Standards
- Section 508 Standards
- Trace EZ Access
- Accessibility for the disabled (part 1), (part 2)
- Irish Accessibility Guidelines for Public Access Terminals