Concentration levels of urea in swimming pool water and reactivity of chlorine with urea

► Concentrations of urea in swimming pools generally range between 0.5 and 1.5 mg/L. ► Urea is very slowly decomposed by chlorine in swimming pools. ► The chlorine demand of urea at neutral pH range between 3 and 5 mol/mol. ► Chlorination of urea (1 mM) leads to the formation of nitrate (up to 0.8 mol/mol).