1.4 Ensure that operation requires minimal strength, grip and wrist twisting
Contents
Using the terminal may require a number of physical operations - pressing buttons or keys, turning knobs or other moving parts, inputting cards or other items and retrieving cards, tickets or other outputs. All these operations should be possible with minimal grip, pushing and pulling strength or twisting of the wrist.
Rationale
Many, particularly older, users have greatly reduced strength due to degenerative conditions that affect muscle power or restrict movements of the joints in the fingers, hands and wrists. Most operations on a terminal require finger or hand movements. If the controls are too stiff, the slots too narrow or the machine's grip on items too tight, some users may not have the strength to overcome this and will be unable to use the terminal.
Directions and Techniques
Favour pressing, but with modest force
As far as possible, avoid using controls that have to be gripped and turned rather than pressed. Allow for a maximum pressing force of 5lbf.
Don't grip outputs too tightly
Ensure that the machine's grip on outputs such as money, tickets, receipts and returned cards is no more than is necessary to prevent them being pulled out by the wind or other environmental conditions.
Make tearing easy
If tickets are delivered using perforated paper rolls, make sure the perforations are easily broken by a tugging motion.
How you could check for this:
Test with real users
To test for this, you should have a prototype used in a realistic situation by real people, particularly older people.
About user testing
Public access terminals - Priority 1- 1.1 Ensure that all operable parts are reachable by people of all heights and people sitting in a wheelchair or buggy
- 1.2 Ensure that displays are within sight of people of all heights and people sitting in a wheelchair or buggy
- 1.3 Ensure that controls are adequately sized and sufficiently spaced to be operated by people with limited dexterity
- 1.4 Ensure that operation requires minimal strength, grip and wrist twisting
- 1.5 Ensure that the terminal can be operated using only one hand
- 1.6 If using a touchscreen or contact-sensitive controls, do not require that it is touched by a body part
- 1.7 Ensure that users with restricted or no vision can use all functions of the terminal
- 1.8 Ensure that all outputs can be perceived by users with restricted or no vision
- 1.9 Ensure that all outputs can be perceived by users with restricted or no hearing
- 1.10 Use the simplest language possible for instructions, prompts and outputs and, where possible, supplement it with pictorial
- 1.11 If using cards, ensure that the card can be inserted into the card reader in its correct orientation without requiring vision
- 1.12 If using biometric identification, provide an alternative access security mechanism for users who do not possess the required biological characteristic
- 1.13 Do not cause the screen to flash at a frequency of above 2Hz
- 1.14 When installing the terminal, ensure that users can get to it along an unobstructed path and operate it from a stable position
- 1.15 Ensure that an equivalent service is available through an accessible channel for users who cannot use the terminal
