Social & Preventive Medicine Minimum recommended concentration of free chlorine drinking water at the end of 1 hour is – A 0.5 mg/L B 0.1 mg/L C 1.0 mg/L D 1.5 mg/L 💡 Explanation Minimum recommended concentration of free chlorine drinking water at the end of 1 hour is - ✓ Correct Answer: A. 0.5 mg/L