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Making maps accessible

simon gray 2023-03-01, 02:13:14
Read this article aloud — 1443 words

How many times have you been to read the Accessibility Statement of a website, and if it’s even mentioned maps, it’s said ‘unfortunately it’s not possible to make maps accessible’?

I was recently asked by a colleague to comment on the accessibility issues of a request by an internal department to put some interactive maps online. It transpired along the way there had been some confusion between the terms ‘access’ and ‘accessibility’, because when I went to look at the content in question in order to form an opinion I couldn’t actually access it anyway, because it was on an external party’s Sharepoint site protected by a login, and it turned out it was that aspect they wanted some help with.

So at the point of my initial reply to the email, without having seen the content, all I was able to respond was - to my shame - ‘because there’s an understanding there’s no real solution to making maps accessible, maps are generally allowed to be exempt from accessibility requirements’. I hopefully redeemed myself with my next sentence by adding ‘however, in many cases something at face value looks like it’s not possible to make it accessible, but with a degree of imagination it’s often possible to make it more accessible than simply not bothering, and the team would want to explore this with you before simply creating a link to your inaccessible maps’.

Map-based input

If the online service in question is a form the purpose of which is for the user to mark a point on a map where something has happened, then that’s easy to make accessible, and saying we can’t make these sorts of maps accessible is a complete cop-out.

Whilst the user in question might have an accessibility need meaning they cannot perceive a map and click a point on it, more often than not they’ll know what street in what area of the city the incident happened, and if they don’t know the door number they’ll know enough information about local landmarks (eg ‘just a bit down the road from Tescobury’s’) that if you offer the user a useful text input alternative, they’ll be able to give you enough information that when you send somebody out to attend to it they’ll find what’s being reported; after all, rarely are very small problems being reported in very large spaces.

If the user is actually on the scene when they want to make their report, it’s usually going to be even easier still - the user will almost certainly have their phone with them, which will almost certainly be able to determine their GPS location. Or, they might be on the scene of the issue right now but not be in a position to report it until later - but if they take a photo of it, their phone will almost certainly mark the GPS location into the EXIF metadata of the image. I’ve been doing some background work on making use of this - it’s actually trivially easy to extract the lat/long coordinates with php code of a standard jpeg image taken by most Android phones; it’s proving a little trickier to work out how extract the location from a modern HEIC image as Apple phones default to creating, but I’ve seen some pointers to that and I’ll share some sample code in due course.

But in a nutshell, if you are not providing an easy to use text-based alternative to map-based input, you are almost certainly failing accessibility requirements.

Map-based output

After I sent my reply to the service wanting help with enabling access to these maps, they quickly responded suggesting a meeting time to explore the question further. For the first part of the meeting I was still under the impression they wanted help with accessibility rather than access, so that was the approach I took, where it became apparent that indeed yes, with a little imagination it should be perfectly possible to make these maps accessible.

The principles of Universal Design have it that a product or service should be so well-designed that there is no need for an alternative to cover certain accessibility needs. In the built environment, a good ramp instead of steps will remove the need to have a bad ramp alternative to bad steps. Lights which turn on and off automatically as a user enters a room - or doors which open and close automatically as a user approaches or leaves them - are examples of Universal Design where a single solution works for everybody. In the realm of words, good content design, where a piece of text makes liberal use of headings and subheadings, and where sentences and paragraphs stick to one major idea separated by those headings and subheadings, should work better for everybody.

But it’s acknowledged that Universal Design does not work, erm, universally. Images need to have an alternative text description for the benefit of people who cannot perceive the image, and therefore cannot determine the information contained within the image.

Which brings us to the interactive maps. It turned out these were going to be used as part of a consultation exercise, with the maps having layers containing different building types in different locations of a certain area of the city. Essentially, they were land use maps to be used as part of a land use consultation exercise.


Which means that in this instance, it will be quite easy to make these maps accessible. The key purpose of the maps is not to enable a user to work out how to get from point A on the map to point B on it, the key purpose is to inform the user that along Wimple Street in Dogbeth there are a number of former industrial buildings for which the proposal is to convert them to residential use, whilst just round the corner to the west of the Dogbeth Canal there is the old Baird Custard warehouse which could be split up into smaller units inside to create a business incubator for the city’s up and coming designer-makers. Etc.


There was obviously more to the maps in question than just those couple of features, but given that a user who is interested in this particular land use consultation will be familiar with the area regardless of whether they can perceive the maps, good artful content design of the text description of the information the maps are conveying, coupled with a good User Interface enabling the user to move around the text of the description as easily as the user can click around a map, means that we should be able to flip the narrative from saying ‘it’s usually not possible to make maps accessible so we don’t need to try’ to instead saying ‘it’s usually just as possible to make maps just as accessible as any other content, so we have an obligation to do so’. Vendors of online GIS systems and enterprise Web Content Management Systems can help content publishers in this by introducing features which can support this kind of micro-level text navigation in a more intuitive and interactive way than just tabbing through headings and subheadings.

And remember, it’s not just screenreader users who might be unable to perceive maps - a sizeable proportion of the fully sighted population has difficulty understanding maps, and even amongst the population who have no cognitive difficulty at all with maps, a point on a map backed up by a text description saying ‘the building with the clock tower next to the old police station’ will enable them to picture in their mind the exact location much more readily than the point on the map alone.

As with everything to do with accessibility, if you make it accessible, you make it better for everybody.

#Accessibility #LocalGovWeb #LocalGovDigital #Manifesto

In group Public / Third Sector Digital

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