This article is a continuation to the first one in this series, check it here – Web accessibility testing – part 1. In the previous one we looked at a few fundamental concepts of what accessibility is and how can it be evaluated using accessibility testing tools.
In this tutorial we will see a couple more accessibility tools, techniques and details.
What You Will Learn:
WAVE (Web Accessibility Evaluation Tool):
WAVE tool is a web accessibility evaluation tool – a toolbar for Firefox browser. It is important to note that, WAVE cannot tell you if your web content is accessible; only a human can determine true accessibility. But, WAVE can help you evaluate the accessibility of your web content.
All evaluation happens directly within the browser and no information is sent to WAVE servers. This ensures 100% private and secure accessibility reporting.
For downloading WAVE web accessibility toolbar go to http://wave.webaim.org/toolbar/ and download it in Firefox browser. Make sure you will open downloading URL in Firefox browser because WAVE toolbar only supports Firefox.
Using the WAVE Web Accessibility Toolbar
Following are the features we can use while working on Firefox browser.
#1) Select the website http://www.easports.com/, then click on the “Errors, Features, and Alerts”, you will find the page with accessibility alerts and errors in yellow colour. Mouse over on the images to see the details of alerts.
(Note: click on any image for enlarged view)
#2) Now click on “Structure/Order View”, you will get the page with Inline Frame details.
#3) Now click on “Text-only View”, the site will display without images, styles and layouts.
#4) “Outline View” icons on the toolbar will let you know if the headings are in order or not.
#5) The “Reset Page” icon will refresh the page.
#6) Clicking on “Disable style” will remove the css styles from the page.
#7) The “Icons Key” button will display a list of all WAVE icons with additional details, information and recommendations.
You can also evaluate the accessibility of the website without downloading the wave tool and directly using it through online.
Steps to verify the accessibility of website:
Step #1) Click on url: http://wave.webaim.org/
Step #2) Enter the Web page address in the text box and hit enter. We are going to use com as an example. So enter the site www.facebook.com in the text box and click on enter button.
Step #3) You will find summary details in left hand side of the navigation.
- Errors would be displaying in red with a count. In my case its showing as 13.
- Alerts would be displaying in yellow with a count 13.
- Features would be in green with a count 10.
- Structural Elements would be 6 in blue color.
- HTML5 and ARIA would be 15 in purple color.
- Contrast Errors would be 14 in black color.
Clicking on each icon will give you more information of the elements as shown above for alert (in center of the page).
Check this WAVE getting started video:
Now, let’s look a different category of tools:
Free Web Page Accessibility Validators:
Few more best Web Accessibility Checker Tools:
- AChecker open source accessibility evaluation tool
- Accessibility Valet
Vision disability tools
Vision disability refers to loss of vision. There are different kinds of Vision Disabilities:
- Low or restricted vision
- Color blindness
Users with visual impairments use assistive technology software that reads content aloud. For Example: JAWS for Window’s operating systems, NVDA for Window’s operating systems, Voice Over for Mac. User with weak vision can also make text larger with browser setting or magnificent setting of operating system. We are going to learn these features with the help of Magnifiers and JAWS tools.
1) Zoom Text Magnifier enlarges everything on your computer screen and making application easy to see and use. You can download it from this link.
To get a good idea of how this works, we highly recommend that you download a free trial version and experiment.
2) Window’s magnifier also enlarges different parts of the screen. We can open it by clicking on Start button from your desktop and then type Magnifier. Click on the program Magnifier. When you mouse hover on the web page, this tool enlarges the size of the screen and displays.
3) Blind computer users, who cannot use a normal computer monitor, use refreshable Braille display or Braille terminal to read text output.
According to Wikipedia, a refreshable Braille display or Braille terminal is an electro-mechanical device for displaying Braille characters, usually by means of round-tipped pins raised through holes in a flat surface.
B) JAWS- Job Access With Speech
JAWS is a screen reader used to test Web Pages on windows operating system that allows visually damaged users to read the screen. JAWS support all versions of operating systems as well as provide refreshable Braille display.
Following are Keyboard commands to use JAWS:
The basic functions that are tested with the help of JAWS are:
- JAWS provide the amount of keystrokes to navigate Web pages. For example Arrow keys, Page Up and Down keys, Home, End, and several other JAWS navigation keys.
- Links, images, and image maps: JAWS provides keystrokes to navigate from one link to another in the Web page.
- HTML Form fields and controls: JAWS provides keystrokes to navigate between form elements
- HTML Frames: Navigate frames with the keyboard.
- Tables: Navigate table cells
This being a brief overview of the different techniques and tools that are used to accomplish the evaluation of accessibility.
Accessibility points for Developers & Testers
- Do all active images have alt-text that indicates what the link or button does?
- Do all decorative images & redundant images have null ( alt=””) alt text?
- Do all information images have alt-text that provides the same information that the images provides?
- Is the page organized with headings? Are they marked as headings?
- Can you access everything using the keyboard?
- Will your page be read in a logical order in a screen reader?
- Is it clear what element is in focus while you use the keyboard access?
- Is all of the important information in video available through standard audio or through added audio description?
Development team can make sure that their product is accessibility compliant by code inspection and Unit testing.
Typical test cases for accessibility testing:
- Make sure that all functions are available via keyboard only (do not use mouse)
- Make sure that information is visible when display setting is changed to High Contrast modes.
- Make sure that screen reading tools can read all the text available and every picture/Image have corresponding alternate text associated with it.
- Make sure that product defined keyboard actions do not affect accessibility keyboard shortcuts.
Web accessibility offers many opportunities for disabled users. However, we have to acknowledge the fact that it is difficult to provide full access for every kind of disabilities or difficulties that could prevent a user from reaching the content of a website.
Steps can be taken but it might not be a 100%. If we follow the standards outlined in this article from initial stage of the development, we can easily create an accessible website for most users.
Feel free to suggest more accessibility testing tools and tips in comments below.