Here is a link to the 2010 ADA Standards for showers and bathtubs.

There is a lot of great detailed drawings and such to make planning a safe and functional shower or bathroom project.

2010 ADA Standards for Accessible Design

I believe the new guidelines and codes go into affect next year. March 15, 2012 if I'm not mistaken.

Best,

John Whipple
By Any Design Ltd.