Gallery multimedia access guidelines
Version 1.1, 2003
John Benfield, New Media Manager, Natural History Museum
020 7942 5491, j.benfield@nhm.ac.uk
Please note:
Visual literacy and competency of users is usually different to that of developers.
It is therefore essential to evaluate the product throughout the development
phase.
AAA indicates mandatory requirements
Interface
- Buttons
- minimum 'finger' size (15mm) (AAA)
- consistently placed and labelled (AAA)
- if buttons represent a category then the active category should be indicated
- visual feedback important on button press, especially on touchscreens
and even more so with delayed actions.
- no mouse-over type feedback can be used on touchscreens.
- If the desired action is triggered on release of the button, you allow
for a release outside of the button for cancellation.
- Restart option
- should always accessible (AAA)
- should offer a 'do you really want to start again' option
- Time-out
- minimum 30 seconds - if necessary use a warning stating that the screen
will reset in x seconds (countdown to zero)
- the system should time-out to a screensaver
- use clear 'touch to start' instruction
- Iconography
- icons should be used sparingly
- icons should be clear and meaningful
- if internationally accepted versions are available use these (eg 'i' for
information)
- for language icons do not use flag, rather use the name of the language
in that language
- Cursors - always use and make obvious (except for touchscreens where
the cursor should be hidden to prevent confusion)
- Delayed actions - if an interaction results in a delay of more than 3
seconds consider a 'please wait' intervening screen
- Sound - feedback on press is recommended (where galleries are sound sensitive
seek advice from the Project Manager)
- Strobe effects - two cycles per second or less (strobe effects can cause
headaches, migraines and even epilepsy) (AAA)
- Make the interface intuitive and consistent.
- Animation.
- Use Animations (flash or blink) to draw attention to changes onscreen
or to vital elements.
- Animations can be distracting, so only use where and when necessary.
- Transitional Animations can keep the user interested, but not if they
are slow and cumbersome (keep them < 1 - 2 seconds)
Navigation
- Ideally, leave a navigational trail, so that users can easily remember
where they are
- It is a good idea to have some indication of which pages have been visited
in the current session
- Colour-code categories and subcategories as a navigational aid
- Keep the depth of information to a maximum of three levels
- If there is a sequence of elements (eg pages, animations, videos) indicate
where the user is within the sequence
- Help options
- ideally shouldn't require 'help' option
- if having to use help then the advice should relate to where the user
is at that time, not just general help
Hardware
- Input methods - preferred:
- touchscreens - ensure that the touch sensitivity is neither too sensitive
nor requiring too hard a press
- trackballs (minimum diameter 38mm, can be bought from Traxsys)
- joysticks
- panel buttons (minimum 15mm across)
- Prohibited methods:
- keyboards (except virtual and concept keyboards if appropriate - please
seek advice from the New Media Manager)
- mouse
- Housing
- height - minimum 700mm, max 800mm (AAA)
- wheelchair access - allow access underneath the kiosk to a depth of 300mm
(AAA) - this may not always be possible if the housing is wall-mounted
- screen angle
- should be greater that 50 degrees
- make adjustable if appropriate
- test for screen glare
Content
- Type
- accessible body text (Arial or Verdana) - graphic text can be more stylised
although should still avoid obviously inaccessible fonts
- font size minimum 14 pt (AAA)
- left justify (AAA)
- average word length of five to nine words per line.
- leading should allow sufficient line spacing to be readable
- kerning should be sufficient that letters have clear separation, but not
so much that the word integrity is lost
- no ampersands
- not too much text - ideally less than 80 words per screen
- 70 percent contrast between text and background - this is difficult to
measure accurately, but common sense should be used (AAA)
- colour blindness - avoid red/green combinations, also be aware of yellow/blue
(AAA)
- On-site testing must be carried out as early as possible. If access issues
are identified late in a project they should be rectified as a priority.
- Video - should be closed captioned, or a précis transcription
should be provided (AAA)
- Be aware of different intellectual access needs (seek advice from the
Museum's Access Officer)
- Copy should be checked by the Museum's in-house editorial staff
Gallery multimedia Access Audit
Project title
Project manager (print name and signed)
Developer name (print name and signed)
Gallery location
Date audit submitted
Internal approval (signed New Media Manager / Access officer) |
|
Access criteria |
Value |
Comments |
| Minimum Type size used |
Numeric |
|
| Body Font style |
Name |
|
| Text background contrast: |
Checked |
|
| Copy checked by NHM editorial |
Checked |
|
| Colour combinations |
Checked |
|
| Restart always accessible |
Yes / No |
|
| Interaction method |
Touchscreen etc |
|
| Minimum button size |
Numeric |
|
| Wheelchair access |
Yes / No |
|
| Video interpretation: Captions/Transcript |
Captions/Transcript |
|