Making screen content accessible to more people

Make text big and high in contrast, leave each slide up long enough to read, and never rely on colour or sound alone to carry the message. Caption any video with speech in it, avoid anything that flashes, and put screens where people sitting down can see them too. Anything essential, such as allergens or safety notices, should be available another way as well, because some customers won't be able to use a screen at all.

Who you're designing for

Plenty of your customers read a screen differently from you. Some have low vision or left their glasses at home, and some can't tell certain colours apart. Others have dyslexia, don't read English easily, are deaf or hard of hearing, or are looking up at the screen from a wheelchair. Most of what helps them also helps the person in a hurry on a busy Friday night, so it's worth building in from the start.

Text people can read

Size first. Text you can read comfortably from the back of the room might not work for someone with poorer eyesight, so err on the big side. Use a plain sans-serif font in a regular or bold weight, because thin and decorative fonts are the first to break up when eyesight isn't great.

Keep text left aligned when it runs over more than one line, and use sentence case, since whole sentences in capitals are harder to read (more so for many people with dyslexia). Italics are best kept off anything important. Short lines and plain words help everyone, and they help most for people reading in a second language. Designing for screens covers size and viewing distance in more detail.

Contrast and colour

Strong contrast between text and background makes a big difference for people with low vision. The guidelines used for websites (WCAG) ask for a contrast ratio of at least 4.5 to 1 for normal text, and free online contrast checkers will tell you whether a pair of colours passes. A screen across a room has glare and distance to deal with as well, so aim comfortably above the minimum.

Don't let colour carry meaning on its own. Red for full and green for available means nothing to someone who can't tell red from green, which is one of the more common kinds of colour blindness. Add the word. In the Casty demo, Fitzroy Gym's timetable shows "Full" as a word on a coloured label, so it works with or without the colour.

A quick test: take a screenshot of the layout, turn it black and white in your phone's photo editor and look again. If something important disappears, it was relying on colour.

Time, movement and flashing

Slides that change before someone has finished reading shut out slower readers, and anyone whose eyes take a moment to find the screen. Time each slide by reading it aloud slowly and adding a few seconds, and keep things people study, like menus and timetables, on screen for as long as they apply. How long each slide should stay on screen goes into timing.

Movement needs more care. Scrolling tickers, constant animation and busy transitions can make a screen hard going for some people, and fast scrolling text is difficult for nearly everyone. Use movement to catch the eye, briefly, and keep the words still.

Avoid anything that flashes. Flashing and flickering content can trigger seizures in people with photosensitive epilepsy, and the web guidelines say nothing should flash more than three times in any one second. Watch promotional videos from suppliers before they go on screen, because some are cut fast with strobe effects.

Video and sound

Most venue screens are muted, so a video with speech needs captions burned in, or it says nothing to anyone, including deaf and hard of hearing customers. For live streams, the HLS widget in Casty has an Enable Subtitles? setting for streams that carry subtitles.

It works the other way round too. If something is only ever said out loud, like last orders or a class moving to another studio, put it on the screens as well, so people who didn't hear the announcement still find out.

Where the screen goes

A screen high above the bar is easy to see over a standing crowd and awkward from a wheelchair or a low table. Put information people need to read closely, such as menus, at a height that works sitting and standing, and keep the top of the wall for things that only need a glance. Avoid spots facing a window, where glare washes the screen out for part of the day. Touch screens bring their own questions about reach, and they're worth thinking through separately before you buy one.

Don't make the screen the only way

Some people can't use a screen however well it's designed, such as someone who is blind or someone who simply can't see it from where they're sitting. Anything they need, including allergen information, prices and safety notices, should also be available in print, on your website or from staff. For food businesses this matters most with allergens, and allergen information and digital menus goes into it.

The law, briefly

In England, Scotland and Wales, the Equality Act 2010 expects businesses that serve the public to make reasonable adjustments so disabled people aren't put at a substantial disadvantage. It doesn't set out rules for screens, and what counts as reasonable depends on the business. Read the Equality Act 2010 and the official guidance, or take advice, if you're unsure what it means for you.

Ask someone to check

The quickest check is to ask. Get a couple of people who'll be honest, ideally including someone who wears glasses and someone who's colour blind, to read your screens from where customers stand and tell you what's hard. It costs nothing and usually turns up something you'd missed.