1.11 If using telephone cards, ensure that the card can be inserted into the card reader in its correct orientation without requiring vision
The user should be able to distinguish a phone card from other similar cards, turn it the right way round and insert it into the reader without being able to see the card or the reader. If the card is still inserted in the wrong orientation, it should be immediately rejected and the user should be notified of the error and allowed to try again.
In your wallet or purse, you probably have a number of different cards for identifying yourself to different authorities or operating different machines or doorways. Often, the only distinguishing features on the cards are visual - the colours and what is written on each card. Ask yourself "if it was dark or I was unable to see, how would I know which card to use?".
Having retrieved the required card, you will normally have to put it into a slot or run it through a swipe card reader in a particular orientation and direction. Ask yourself "how would I know which side is which and which end is which? And even if I knew, how would I know which end should go into the slot or past the reader and which side should be up or down or to the left or right?". The answer will usually have something to do with looking at both the card and the slot or reader. A user who has poor or no vision or who is working in a dark place will have none of this information and will therefore have to resort to trial and error. If they choose the wrong orientation, they may be able to try again until they get it right. If they choose the wrong card, they may be in a much worse situation.
Directions and Techniques
Distinguish phone cards with tactile markings
Incorporate an embossed capital letter at least 10mm high with an embossing of at least 0.7mm. Note that, whilst Braille may seem a more obvious solution for tactile marking, less than 2% of visually impaired people can read Braille.
Incorporate an orientation notch on the card
A 2mm notch on the trailing edge of the card will enable the user to correctly orientate it for insertion into a horizontal slot by touch. This follows the CEN standard EN 1332 (Machine readable cards, related device interfaces and operations. Part 2 Dimension and location of tactile identifier for ID1 cards). Note that the slot should also be orientated in a way that fits the standard.
Allow the card to be inserted in any orientation
If possible, the card reader could be designed so that the card can be inserted or swiped in any direction and with either side uppermost or leftmost. This will remove the possibility of errors. It does not, however, mean that there is no need to add an orientation notch on the card, since users who do not realise that any orientation is acceptable will then be unsure of what to do.
Generate an audible error indication when the card is inserted in the wrong orientation
If the card is inserted in the wrong orientation, immediately reject it and notify the user of the error using an audible indicator such as a low beep which suggests failure. Then allow the user to try again.
Consider using contactless cards
Contactless cards work at a distance. They do not need to touch the reader device or to be placed in any particular orientation. The maximum working distance is typically no more than 10cm for security reasons. Other types of cards include those that must be pressed onto a pad but can be in any orientation.
Consult international standards
International standards relating to card systems include:
- CEN (Comite Europeen de Normalisation) EN 1332 & EN 726
- ISO (International Standards Organisation) 7816 & ISO/IEC 10536
- ITU (International Telecommunication Union) ITU-T E.118 & E.133
How you could check for this:
Self-test early prototypes
Designers can run simple tests themselves on an early prototype, by simulating sightless use. This can be done either by wearing a blindfold, turning off the lights or putting cards in a black bag. If working blindfolded or in the dark, extreme care should be taken to avoid injury through loss of balance or collision with unseen objects. This may require that the test user remains seated or, if they have to move around, obstacles such as floor cabling are removed in advance.
Test with real users
During development, you should test the prototype in a realistic situation with real people who have complete visual impairment. In particular, you should include people who are recently impaired and have not yet developed enhanced tactile abilities.
About user testing