Hello all ,
I am under the process of designing signages keeping Universal design fundamentals.If anyboby is having any material or links regarding the same please share it , it will be of great use in my research .
Material choices depend on application and sign use. Do you have a brief of what type of signage you need to design?
I am working on road signages for different user groups.Legibility for the users with disabilities also Visibility and clearity.
The November issue of IdN Magazine  is on wayfinding and signage. Only the first half of the issue was on that topic however. I have only seen it on the rack at a few stores, so you might want to just order an issue.
You might be interested in this - http://www.nytimes.com/2007/08/12/magazine/12fonts-t.html?_r=3&pagewanted=all It's an article about Clearview typeface for road signs and the research to designing it.