You are volunteering your time to,do the quilting. You should not have to try to clean the tops brought to you. You are just going to have to tell the person who organizes the volunteer work that you can't work on things from pet households. You should.not feel,bad about it. The person who brings you something with ani,al hair and dander is the one who should feel,bad. Loose hairs on a top get quilted in and don't go away with washing.
I quilt for others, and I don't let my cats in my sewing room. There are too many people sensitive to pet dander.