Actually I wasn't planning to make a policy that says "library staff will
only spend x hours per day per patron with a disability".  Because our
problem is mainly with people with disabilities, I'm trying to figure out
what is a reasonable amount of time per day for library staff to spend with
patrons with disabilities, then we will make a library policy that says
something along the lines of "library staff are not able to spend more than
x hours per day per patron".
  Katherine Rankin
  University of Nevada, Las Vegas Libraries