21. Cats that are kept indoors must have access at all times to a litter box that
(1) is made of a non-toxic material that can be washed and disinfected easily;
(2) is in good condition, free of parts jutting out and sharp edges or other potential causes of injury; and
(3) contains a sufficient amount of regularly-replaced absorbent litter, to avoid odours and the accumulation of feces and urine.