W3C home > Mailing lists > Public > w3c-wai-gl@w3.org > October to December 2001

Re: ems versus pixels

From: Kynn Bartlett <kynn-edapta@idyllmtn.com>
Date: Mon, 31 Dec 2001 19:49:51 -0800
Message-Id: <a05101001b856e18b8e69@[10.0.1.3]>
To: <rowan@absolutely.co.nz>, <w3c-wai-gl@w3.org>
I smell a FAQ.  Hey, fellow WCAG members, why don't we have a FAQ,
anyway?  (For that matter, why doesn't ANYONE seem to have a detailed
FAQ on web accessibility?  Maybe I should make one, in my infinite
free time!)

Rowan, in general pixel sizes for positioning are not a huge barrier
to access but don't necessarily help it -- well not more than you
already assist access by putting pages in CSS.  (Since you can turn
those off and such.)

In theory, em sizes for positioning are kinda helpful because it makes
it more likely that you'll be able to fit your text into the page; by
using one set of units for all values in your layout, you can get
closer to whatever design you might want.  In practice, I don't think
it's that big a deal, though.

Other people may disagree. :)

--Kynn


At 4:32 PM +1300 1/1/02, Rowan Smith wrote:
>Hi there
>
>WAI Priority 3 guidelines (WCAG Checkpoint 3.4) recommend using relative
>units rather than absolute. The Techniques document suggests that using ems
>rather than pixels as a unit is a way of doing this even when using absolute
>positioning.
>
>OK, I can understand that for text specifications like font sizes and line
>heights, but does it apply to positioning layers on a page using CSS? Is
>there an accessibility downside of positioning layers (div tags) by using
>px?
>
>Thanks
>
>Rowan


-- 
Kynn Bartlett <kynn@idyllmtn.com>                 http://kynn.com
Chief Technologist, Idyll Mountain            http://idyllmtn.com
Web Accessibility Expert-for-hire          http://kynn.com/resume
January Web Accessibility eCourse           http://kynn.com/+d201
Forthcoming: Teach Yourself CSS in 24 Hours
Received on Monday, 31 December 2001 22:50:14 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:47:17 GMT