Accessibility Policy

Description of target user population

A report by FLOW interactive on users of the ONS website in October 2007 supported earlier work on user personas by confirming that there were three main personas: Pressured Analysts, Thorough Researchers and Citizens.

The first two groups represent professional users of statistics with a strong interest in accessing data, whilst the third group represents a far more diverse group of people seeking information.

The IPSOS Mori report (May 2009) found that 29 per cent of NS Online users come from the education sector, 25 per cent from the private sector, 7 per cent from local/regional government and 16 per cent from the general public.

There will be a percentage of users in all of the above groups who suffer from the disabilities identified by the Central Office for Information (COI), namely:

• Vision – including blindness, colour blindness and tunnel vision

• Hearing – both deaf and hard of hearing people

• Mobility problems with hands and arms

• Cognitive, Mental and learning disabilities*

There will also be a percentage of users, particularly in the last group, who lack Level 1 Numeracy skills (dealing with percentages and fractions).

A recent survey in Wales showed that 53 per cent of all adults belonged to this group.

It should be noted that whilst interactive, animated, video or audio content can present accessibility barriers for some users, it can enhance accessibility for other users.

For example, users with cognitive and learning disabilities may prefer to access data in a non-text based format.

*This list is the one used by the COI in TG102 and in PAS 78 (see Accessibility Annex). The current W3C guidelines use a slightly different list.

Core tasks

All visitors to the ONS website should be able to access (whether by browsing, searching, or directly accessing):

• ONS data*

• ONS publications

• ONS summary information (statistical bulletins)

• News releases

• Information on how statistics are compiled

• Corporate ONS information

*This is the most important task, as the 2009 IPSOS Mori research indicated that 79 per cent of ONS website users were looking for ‘data and figures’.

Analysis of needs

The ONS website is used to publish content that is significantly more complex than other content commonly found online.

We have taken care to analyse the best ways in which we can present our complex outputs in an accessible format.

Firstly, we have provided three alternative viewing schemes for the website (as detailed in the Accessibility Features) in order to ensure that those with visual or cognitive impairments can read the content on our webpages as easily as possible.

Secondly, a group involving representatives from the ONS Data Visualisation department and Communication Division has worked on producing colour palettes for use on the new website that take into account common visual disabilities (such as colour blindness).

These palettes include colour schemes for use with graphs and maps, and ensure that the WCAG WAI v1.0 section 2.2 requirement is met.

Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having colour deficits or when viewed on a black and white screen. [priority 2 for images, priority 3 for text].

Thirdly, we have consulted with the Central Office for Information (COI) and AbilityNet on the best way to present our complex data online. This advice has covered a number of issues, but particularly tabular data.

The advice received about tables indicates that allowing tables to extend beyond the natural size of a webpage viewed at 1024 x 768 resolution and necessitating the use of a horizontal scrollbar is less than ideal.

Whilst accepting that this may occur - particularly if a user is allowed to choose what data to view – the best approach to data likely to require a significant amount of horizontal scrolling is to provide the data in a downloadable format.

For tables:

• absolute sizing should be avoided

• names and titles should be provided using the <caption> tag

• WCAG WAI v1.0 priority 1 should be followed (1) for data tables, identify row and column headers and (2) for data tables that have two or more logical levels of row or column headers, use markup to associate data cells and header cells

• where possible, WCAG WAI v1.0 priority 3 should be followed: (1) provide summaries for tables and (2) provide abbreviations for header labels

For maps and charts:

• long descriptions should be used where possible (whether this is provided next to the map/graph in the page, linked to, or as part of the ‘alt’ text description). These descriptions may be other documents released with the data (e.g. press releases) and are expected to summarise key points

• the WCAG WAI v1.0 priority 1 should be followed: (1) provide a text equivalent for every non-text element (e.g., via ‘alt’, ‘longdesc’, or in element content) and (2) ensure that all information conveyed with color is also available without color, for example from context or markup

Exceptions

1. Legacy content

We have noted in the Accessibility Statement that:

This website includes a large body of legacy content that dates from the previous ONS website.

This content is not all accessible to the WCAG v1.0 level double-A standard and making all of this content retrospectively accessible would not be an effective use of our resources.

We are monitoring the most frequently accessed documents that fall into this category and embarking on a program of converting these to an accessible format.

2. PDF content not covered by the above

We will endeavour to ensure that PDFs included on the website are as accessible as possible.

However, our nominated route for focusing on providing content that meets WCAG WAI v1.0 double-A standards is as HTML formatted webpages and we are working towards ensuring that our content is all available either in this way or as an accessible data download (e.g. as an XLS or CSV file).

3. Issues not covered in the WCAG WAI v1.0 guidelines

JavaScript may be used, but all functionality must also be available when JavaScript is switched off.

For example, JavaScript may be used to apply a chosen filter option to a search, but If JavaScript is turned off the user must still be able to filter their search result in another way.

AJAX should not be used on the ONS website until the current issues that it causes with screen readers and other accessibility aids are solved.

Pop-up windows cause problems for all users with security settings and so-called ‘pop-up blockers’, as well as posing a particular challenge to screen reading software.

Links on the ONS website should never be set to open in a new window, with two exceptions:

1. The use of JavaScript to open a new window to allow the user to, for example, bookmark a page without navigating away from the page. This should be allowed only when there is a non-JavaScript option that does not use a pop-up.

2. When the user chooses to make a interactive element full screen in order to view the content more easily. The interactive element should never default to full screen mode, but display on the page and allow the user to choose to enter full screen mode.

Rich Media content

The accessibility statement says:

The ONS website will occasionally use ways of presenting data and analysis that are not accessible to the WCAG WAI v1.0 double-A standard in order to aid interpretation and enhance accessibility for some groups of users.

When we do this, we will take all possible steps to ensure that an alternative version is made available in an accessible format that meets the WCAG WAI v1.0 standard.

Examples of this might include providing a transcript for video or audio content or providing a data download to provide the data used in an animated presentation.

In practice, this means that when data is presented in an interactive format on the ONS website (for example, SVG or Flash), the data being used to create the animation should be provided as a download in CSV or XLS format.

A description of the key points should also be given where possible – though this may well be in the shape of other content released with the data (for example, Statistical Bulletins, News Releases etc.).

Where an exploratory interface is used, it is recognised that it may be impossible for producers to anticipate the key stories present for a user when they navigate through the data.

In these cases, a textual summary of the purpose of the interface should be given alongside the link to download the data used.

When audio or video content is used, a transcript must be provided.

If the content is also provided on a third-party website, the transcript or alternative data must be provided there if possible (for example, on YouTube, provide a transcript in the comments section).

As noted earlier, whilst interactive, animated, video or audio content can present accessibility barriers for some users, it can enhance accessibility for other users.

For example, users with cognitive and learning disabilities may prefer to access data in a non-text based format.