Chemically-treated nonmedical test strips for measuring the level of chlorine in liquids; Chemically-treated nonmedical test strips for measuring the concentration of quaternary ammonium compounds in solutions; Chemically-treated nonmedical test strips for measuring the acidity or alkalinity of a solution; Chemically-treated nonmedical test strips for measure the concentration of iodine in solutions; Chemically-treated nonmedical test strips for measuring the concentration of peracetic acid i...