What is normally acceptable?

I'll be a CNA next month. I may end up working for an agency at first, so I will rotate between several nursing homes and hospitals.

What kind of shoes do I need? Will I be ok with any white sneakers or are some facilities strict about the shoes being completely white, or...what? I want to make sure none of the facilites will have a problem.

Will I be all right if I get some white New Balance or Saucony's or is it better to get something a little more traditional looking that I can wipe off if they get dirty?

I have wide feet at the toes. Suggestions?