Guidelines

• Good visual contrast between the keys and the body of the phone.
• Key tops should be convex or flat with a raised edge.
• Keys should be as large as possible without reducing the distance between the keys to less than half the key width.
• Ideally the keys should be internally illuminated, but the internal illumination should not reduce the legibility of the numbers in daylight.
• The visual markings on the keys should be high contrast, clear, and as large as is possible on the key top.
• Keys should be raised above the body of the phone (preferably by 5 mm).
• The pressure to activate a key should be between 0.5 and 1 Newton.
• There should be auditory and tactual feedback of key activation.
• Function keys should be tactually discernable from the numeric keys.
• There should be a tactual indication on the '5' key or on a QWERTY keyboard on the 'F' and 'J' keys.
• A voice mode selection that announces all key presses.
• One-touch buttons are provided for ease of calling telephone numbers stored in the memory.
• Provide rotational or linear-stop controls.
• For keys that do not have any physical travel, audio or tactile feedback should be provided so the user knows when the key has been activated (e.g. a toggle swtich or a push-in/pop-out switch).
• There is the ability to switch on or off any buttons on the side of the telephone.
• Where timed responses are required allow the user to adjust them or set the amount of time allocated to the task.

• The display should have good contrast and use a clear typeface.
• Text should not be scrolling or flashing while it has to be read.
• There should be minimal visual flicker or image flashing.
• Minimise glare on the display and control surfaces.
• Provide adequate back lighting.
• There is the ability to alter the length of activation time for the back lighting.
• The user should be able to increase the font size.
• Text should be in upper and lower case and not all in capitals.
• Use Arabic and not Roman numerals.
• On colour displays, red/green and blue/yellow combinations should not be used.
• Provide colours with different hues and intensity so that coloured objects can be distinguished on a black and white screen.
• On flip-type telephones a good front screen should be provided.

• The SIM card should be easy to insert in the correct orientation.
• The phone should be easy to hold by someone with a weak grip.
• There should not be parts which can easily come off.
• The phone should be able to lie on a table and be operated one-handed (non-slip material on the underside of the phone would help to hold the phone in place if it is used while lying on a table).
• Any external antenna should be robust and not require extending by the user.

• There should be consistent design of the user interface adhering to the relevant standards whenever possible.
• There should be an audio and visual indication when the phone is switched on or off.
• The user should be able to return to the previous state or return to the default status at any stage in the process.
• Error messages should be comprehensible to the non-technical user.
• All labels and instructions should be in short and simple phrases or sentences. Avoid the use of abbreviations where possible.
• Basic functions should be usable without having to use the visual display.
• It should be possible to use the phone one-handed.
• Possible speech recognition dialling for telephone numbers not already listed in the address book.
• There is the option to associate a photograph with a telephone number in the address book.

• The user should be able to set the volume of the ringing tone.
• The ringing/alerting tone should include low as well as high frequencies.
• The user must be able to increase the volume of the audio signal (preferably to at least 90 dB SPL).
• Provide text versions of audio prompts that are synchronised with the audio so that the timing is the same.
• There should be audio cutoff when an external listening device is connected.
• An industry standard connector for headphones or personal listening devices should be provided (e.g. a standard 9mm miniature plug-in jack).
• There is the ability to install assistive technology (e.g. screen reader) directly onto the phone.

• The battery should be easy to install or replace.
• Provide both an audio and visual indication of battery status.
• The telephone should emit a 'beep' or tactile response when the charger is connected correctly.
• It should not be possible to connect the charger incorrectly.
• The charger should not be tricky to use or difficult to handle (i.e. small awkward parts can be difficult to assemble for someone with reduced manual dexterity).

• An infra-red or wireless port could permit connection of computers and assistive devices. For instance, a visually impaired user could get synthetic speech through their own assistive device; an alternative mechanism is to incorporate speech output of SMS (short message service) as a network facility (this does not tell the user about signal or battery strength which is a function of their terminal).
• Provide connection to a hands-free device.
• Reduce interference to external hearing technologies (including hearing aids, cochlear implants and assistive listening devices) to the lowest possible level.
• Provide a means for effective wireless coupling to hearing aids.
• Provide tactile indication on any plug or insert.
• Provide a bevel around the slot or connection point.

• Use simple clear concise language.
• Have a table of contents and a good index.
• Be task orientated.
• Provide alternate formats (e.g. audio tape, large print).
• Provide alternate modes of delivery (e.g. fax, relay service, TTY, Internet posting).
• Use a typeface with good legibility.
• Information contained in pictures should also be explained in the text.
• Provide information on what to do if the phone does not work correctly, or the user is unable to understand the instructions (e.g. a telephone help number).

• 36 CFR Part 1193 RIN 3014-AA19 (1998) Telecommunications Act accessibility guidelines - Section 255
• 47 CFR Part 6 Access to telecommunications service, telecommunications equipment and customer premises equipment by persons with disabilities
• ACIF C625:2005 Information on accessibility features for telephone equipment
• EG 201 472 (2000) Human Factors (HF); Usability evaluation for the design of telecommunication systems, services and terminals
• ES 201 381 (December 1998) Telecommunication keypads and keyboards: Tactile identifiers
• ETR 029 (1991) Access to telecommunications for people with special needs: Recommendations for improving and adapting telecommunication terminals and services for people with impairments
• ETR 345 (1997) Characteristics of telephone keypads and keyboards; Requirements of elderly and disabled people
• ETS 300 381 Telephony for hearing impaired people: Inductive coupling of telephone earphones to hearing aids
• ETS 300 488 (1996) Telephony for hearing impaired people: Characteristics of telephone sets that provide additional receiving amplification for the benefit of the hearing impaired
• ETS 300 679 (1996) Telephony for the hearing impaired: Electrical coupling of telephone sets to hearing aids
• ITU-T E.161 (2001) Arrangements of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network
• ITU-T P.370 (1996) Coupling hearing aids to telephone sets
• JIS X 8341-4 (2005) Guidelines for older persons and persons with disabilities - information and communications equipment, software and services - Part 4: Telecommunications equipment
• TCR-TR 023 (1994) Assignment of alphabetic letters to digits on push button dialling keypads
• TIA-504-A (1998) Telecommunications - Telephone terminal equipment - Magnetic field and acoustic gain requirements for headset telephones intended for use by the hard of hearing.

• Chandler, E. (2006) Mobile devices heuristic evaluation instructions. [accessed 11/06/07].
• Chandler, E., Dixon, E., Pereira, L. M. & Espadinha, C. (2006) A comparison study between a heuristic evaluation technique and end user trial for mobile phone accessibility. [accessed 11/06/07].
• Gill, J. (2000) Mobile telephony: will future developments be accessible to visually impaired
  users? [accessed 07/06/07].
• Nokia Accessibility. [accessed 11/06/07].
• RNIB (2006) Mobile phones: Owasys is a reality. [accessed 07/06/07].
• Trace Research and Development Center (n.d.) Reference designs for cell phones. [accessed 11/06/07].
• U.S. Architectural and Transportation Barriers Compliance Board (n.d.) Bulletin #7: access to telecommunications. [accessed 11/06/07].

• E-Consultancy (2007) Internet statistics compendium. [accessed 21/08/07].
• Glennon, L. (2007) Why can't the phone makers build handsets for everybody? The Guardian - Technology: 6, October 11.
• Mobile Data Association. [accessed 05/11/07].
• Mobile Data Association. Text-it - Latest text figures. [accessed 05/02/08].
• Multimedia Intelligence (2007) Multimedia mobile phone shipments surpass TV shipments in 2008 according to MultiMedia Intelligence. [accessed 04/02/08].
• National Statistics (2007) Use of ICT at home. [accessed 11/06/07].
• Sony Ericsson Special Needs Center. [accessed 11/06/07].
• Trew, Gregory Smith (2005) Starter kit mobile telephone evidence. (PDF) [accessed 11/06/07].

The author would like to thank Fiona Miller for her additional comments and ideas.