sentence: Different blocks are made with different chemicals, like paradichlorobenzene or naphthalene.
sentences_before: The blocks are used to kill germs and take away the bad smell of urinals in public bathrooms. They are put over the urinal drain and evaporate very slowly. Because they do not dissolve or break apart in water, they do not take away the smell of the flushing water or urine.
concept_name: different block
headings: Urinal deodorizer block
categories: Hygiene