Conflict with Browser Built-in Commands

Access keys can be numeric or letters of the alphabet. For example, in earlier versions of Website Designers sites, Website Designers mapped "h" as the access key for the Home page, "m" for the "Site Map", "s" for the search box, and so on.

In practice however, because of the way web browsers implement the access keys, the only access keys you can use for your website are the numbers.

Take Internet Explorer 6 for Windows as an example. If you mapped "h" for your Home page, and "f" for your Feedback form, what happens when someone types Alt+H or Alt+F to invoke the access keys? In the first example, the Help menu will open. In the second example, the "File" menu will pop up.

There goes the shortcut to your home page or feedback form. Since menus vary from browser to browser, and plugins, add-ons and extensions used by your visitors may add to the menus available, if you really want to help those who need accessibility aids, you cannot use any of the letters of the alphabet.

In other words, you only have the 9 digits to use. And that is assuming someone doesn't create a browser menu that is activated by an Alt+number.