Not allowing "Text Size Increase/Decrease" In Browser

I would like to learn how to turn this off.

[SEOdevhead]

I don't want to allow any of my visitors to be able to change the text size of my site from within their browser. For instance you can go to 'View->Text Size->Increase/Decrease' and the text on the website will change size. How can I stop this from happening. I know this is not good accessibility wise, but I need to disallow it nonetheless. Thanks for any tips.

[rocknbil]

Use fixed font sizes in your CSS.

[SEOdevhead]

As in px and not em/%?

[jimbeetle]

pt -- it'll really drive your users crazy ;). Just be very, very sure to preview it in as many screen resolutions as you can.

[Robin_reala]

Fixed px sizes only work in IE - there's no way bar presenting the entire thing as an image for everyone else.