There isn't any precise size for lap quilts. You might check with the organization and see if they can give you a more exact size. What a wonderful ideal to make quilts for chimps. I make beds for the local animal shelter for the cats. I make lap size quilts for foster kids and the size requirements are minimum size of 50"x60". This is a great way of practicing your FMQ because the animals never complain about the quilting!
