Do It Myself Blog – Glenda Watson Hyatt

Motivational Speaker

Do Your Flashing Ads Cause Seizures?

Filed under: Blog Accessibility — by at 11:49 am on Tuesday, May 25, 2010

Flickering, flashing and strobing effects on webpages can cause some people to have photosensitive seizures.

How Common is Photosensitive Epilepsy?

According to the National Society for Epilepsy, “one in 131 people have epilepsy and of these people, up to 5% have photosensitive epilepsy.” This means that for every 10,000 readers or visitors to your site, four or five people could have a tonic clonic (convulsive) seizure caused by flashing ads, animated GIFs or flashing red text.

What are the Recommendations for Bloggers, Internet Marketers and Web Designers?

The two guidelines related to making web content safe for people with photosensitive epilepsy are:

  1. The Web Content Accessibility Guidelines (WCAG) 2.0, Guideline 2.3 requires webpages not to have any content that flashes more than three times per second and no more than three red flashes per second.
  2. The US legislation Section 508 of the Rehabilitation Act, which applies to all Federal agencies, states in subsection 1194.22  Pages shall be designed to avoid causing the screen to flicker with a frequency greater than 2 Hz and lower than 55 Hz.

How Can I Test Flickering Speeds?

For a quick test, download the Web Accessibility Toolbar for Internet Explorer (the lack of toolbars for other browsers is another accessibility issue!).

GIF Flicker Test on the Web Accessibility Toolbar

Once installed, click on Images (keyboard shortcut: alt + 4) on the toolbar, then select GIF Flicker Test.  You’ll be presented with a basic report indicating which GIFs have flicker rates within the range that may affect people with photosensitive epilepsy.

For a more in-depth analysis, check out the Trace Center’s Photosensitive Epilepsy Analysis Tool (PEAT) – a free, downloadable resource for developers to identify seizure risks in their web content and software.

What is the Bottom Line?

Even if the object does not cause a seizure, it may cause nausea or dizziness in some people. Neither of these is as serious of a health risk as a full-blown seizure, but having users mentally associate your web site with feelings of nausea is probably not the best design decision, at least in terms of user satisfaction and repeat visits.

(From: Seizure Disorders)

Where Can I Find More Information?

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Colour Your Blog to Maximize Readability

Filed under: Blog Accessibility — by at 3:17 pm on Thursday, April 8, 2010

In the earlier post 5 Ways to Increase the Accessibility of Blogs, tip #3 is to maximize colour contrast to enhance readability for individuals who are colour blind or has low vision, as well as those of us with aging eyes.

But, how do you measure colour contrast? How much contrast is sufficient?

My favourite colour analyzer, so far, is the Colour Contrast Analyzer application available on the Web Accessibility Toolbar:

Web Accessibility Toolbar with the colour contrast analyzer application

Using this handy application, the contrast between a foreground colour and a background colour can be tested one of four ways, depending upon the information available:

  1. Select the colour from a drop down box,
  2. Enter the HEX code,
  3. Use the eyedropper to choose a colour from the webpage or anywhere, or
  4. Use the red-green-blue sliders.

Screen shot of the colour contrast analyzer

The results are immediately given as either a pass or fail, in accordance with the Web Content Accessibility Guidelines 2.0, which requires a contrast ratio of 4.5:1 (with a few exceptions).

To my understanding, the Web Accessibility Toolbar is only available for the Internet Explorer (IE) browser. (Please correct me if I’m wrong here.)

However, once the Colour Contrast Application is open and even IE closed, the application can be used in other browsers and programs; for example, in word documents to test the contrast between the heading colour and the background colour.

While researching this morning for a few other related posts and projects, I came across a list of other colour analyzing resources, which I’m working my way through:

Which resources would you add the list? What is your favourite colour analyzer tool?

For more tips on enhancing your blog, download the free ebook How POUR is Your Blog?: Tips for Increasing Your Blog Accessibility.

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Are All Video Captions Equally Accessible?

Filed under: Blog Accessibility — by at 5:45 pm on Thursday, January 14, 2010

While writing my latest post for on captioning videos, I had the opportunity to learn a bit more about captioning YouTube videos. I began wondering if how I caption videos is the most accessible way of doing it. Allow me to explain.

When I create a PowerPoint presentation, I also include captions. This means when I capture the presentation as a video, the captions are already there, as in this video on accessible recreation:

Similarly, when I record a video, I use the captioning feature in Camtasia Studios 6, which is fairly easy to do. Captions are automatically added below the video, as in this video message:

This way the captions are always visible, not only for individuals who require them but also to be subtle accessibility reminder to others that videos need to be captioned.

YouTube closed caption button By having the captions always visible – open captions, it saves toggling on captions in YouTube, if, indeed, captions do exist.

How many people even know the arrow in the lower right corner of the YouTube can turn on/off captions when captions are available? Go watch this great video of the WCAG (Web Content Accessibility Guidelines 2.0) Theme Song with the captions turned on. Can the caption feature be operated only using the keyboard? I am still digging for that answer…

Interestingly, if the captions happen to be turned off when I grab the code to add the video to this post, the captions button is no longer available (unless something changes after this post is live), making the captions unavailable to my readers. Really?

My embedded captions are always available, regardless where the video is viewed!

Because of the way I create captions, they are part of the video when I upload to Viddler or YouTube. I do not need to upload and edit a separate captions file. However it does mean when viewers search YouTube for captioned videos, mine are not listed.

Apparently when captions are uploaded separately to YouTube, they can be automatically translated into the viewer’s preferred language, and hence the videos become accessible to a larger audience. I am still looking for an example to verify how this actually works. My captions cannot be instantly translated.

Also, captions, being text, can be searched for, further increasing findability and accessibility. Captions created through PowerPoint and Camtasia cannot be searched via YouTube. 

Finally, when turning on captions in a YouTube video, you can control the look of captions with a few keyboard shortcuts:

  • Increase text size: press "+" key
  • Decrease text size: press "-" key
  • Change background: press "B" or "b" key

My embedded captions are always white text on a black background to maximize contrast and to enhance readability. However, short of watching the video in full screen mode, the viewer has no control over the font size. In future videos I can, however, increase the font size when creating the captions in PowerPoint and Camtasia, if this is an issue.

After this experimenting, I’m left wondering: are some video captions more accessible than others? What is the most accessible method of captioning video?

Share your thoughts and opinions in the comment box below…

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Fresh from WordCamp Las Vegas

Filed under: Blog Accessibility — by at 1:50 pm on Saturday, October 17, 2009

If everything went as planned, Damien Patton are now leaving the stage after a rockin’ panel presentation at WordCamp Las Vegas at BlogWorld!

Thank you to everyone who attended and a big shout out to John Hawkins for all of your efforts!

My presentation “How POUR is Your Blog” is now available as an ebook. Help yourself to a copy and feel free to spread the word widely.

During my presentation, I had the pleasure of introducing the following three bloggers with disabilities in attempts to put faces to the concept of blog accessibility:

Darrell Shandro Darrell Shandrow is an accomplished information technology professional with over ten years of experience in several computer fields including accessibility, customer service, networking, technical support and training. He is also nearly totally blind and relies on a screen reader, which enables him to use computer technology on the job, in the classroom and at home by providing the same information available on the computer’s screen in Braille and speech output.

To give a brief glimpse into what using a screen reader is like: Imagine the entire screen blacked out except for a little square which follows the currently highlighted item. you can only see what is in the little rectangle. To see anything else on the screen requires you to move the square over it using the arrow keys."
For a blind person, this "seeing" involves feeling text in Braille or hearing a voice read it as commands are entered to move the imaginary rectangle around the screen. This leads to many obstacles and frustrations when using the internet.

Darrell blogs at 

Ricky Buchanan Meet Ricky Buchanan. Multiple disabilities and chronic illnesses, causing extreme muscle weakness and severely limited stamina,keep Ricky in bed for 22-24 hours a day.

Yet, being a self-proclaimed geek, she has her computer and various technological gadgets arranged within easy reach so that she can work with minimal physical exertion, while laying on her back in bed.

Ricky is quite active online – her lifeline to the outside world. She blogs at about surviving and thriving while confined to bed, homebound, or otherwise stuck in one place. And at about assistive technology for Apple and Mac users. She also runs No Pity City – Disability gear with slogans that tells it like it is.

Her main theory on life is: I may have disabilities and problems and troubles and stuff that holds me back, but dammit I’m Not Done Living!

Karen Putz Last but definitely not least is Karen Putz – a deaf mom of three deaf and hard of hearing teenagers. Her husband is also deaf.

On top of being a busy Mom, Karen is a sales manager for videophones and relay services for individuals who are deaf and hard of hearing. She is also an avid advocate for the deaf community and a prolific writer and blogger.

She shares her world as a deaf mom on her blog

With more and more content being put online in the format of audio and video without captioning, Karen fears her children will become further excluded from society.

More about WordCamp once I am home. For now, it is par-tay time; after all, this is Vegas!

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5 Reasons Why Bloggers and Web Designers Should Consider Accessibility

Filed under: Blog Accessibility — by at 9:50 am on Tuesday, October 6, 2009

Guest post by Chris Garrett

I have learned a lot about accessibility from Glenda. In particular you should read the excellent free advice contained in her "How POUR is Your Blog" ebook.

Learning from Glenda and other accessibility experts has taught me that some of the changes we can implement are not just the right thing to do, many are really easy and it is only laziness or ignorance on my part that has stopped me doing them.

What I think many bloggers and blog theme designers do not realise though is accessibility is not just about making your blog readable to, say, blind folks. In fact, you should also consider making your site accessible for purely selfish reasons too.

Here are 5 good reasons to make your blog more accessible:

  1. First, the scary reason. In many countries, accessibility is the law. OK, so maybe they are gong to go after the Fortune 500 before us little guys. I don’t know about you but I would rather make my site friendly than risk it.
  2. You are losing customers. There are over 50 million people in USA alone with a disability. These folks are spending money with your competitors because your site is unfriendly.
  3. Accessibility often means more search friendly too. Imagine Google as a blind reader. The bot can not interact with movies, play with your flash, or understand pictures, only how you describe them. Make sense?
  4. People are more and more likely to want to view your content on a non-standard device. Good accessibility means allowing folks to consume your content their way, from screen reader to iPhone, rather than force round pegs into your 1024×768 square holes.
  5. It is good design. Many site owners have found by focusing on content and ease of use rather than bloated widgets, gizmos and images, their accessible sites work faster, are easier to maintain, and provide a better overall experience for ALL their readers and customers.

Really, it just makes sense. It’s not just the right thing to do, it could make you more competitive.

Are you ready to make your site more accessible? What do you think?

Please share your thoughts in the comments …

Chris Garrett is a professional blogger and new media consultant who for nearly 20 years has written about everything from Microsoft Excel through to Travel, but this is the first time he has written about accessibility!

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