Are there national guidelines for using tile on outside handicapped ramps on
Restaurants?

Hello r:

Probably. Check the Americans with Disabilities Act.

excon

I am not familiar with any rules on the actual material they have to be made of. The main rules are that specific firms and buidlings built after a certain date must comply to allow access, and other firms are to make accomidations that are reasonalbe.

I work with wheel chairs daily and even train people to use them for the first time, and I would say that unless this is a rough tile, you would not want the ramp to be slick, and it needs to be something that can be cleared in the snow ( if that happens in your area)

I fall several times a year from poorly designed ramps, wood when wet or light layer of ice is about the worst. Rough concrete is one of the best.