Need Testing method

How can I test residual chlorine in water

1. Kamlesh Banote reply
2. Mehak reply

   I am using potassium iodide,starch and acetic acid for residual chlorine and titrate with 0.01sodium thiosulphate..but acc to procedure color change in a night but my sample doesn…

3. Mehak reply

   Thanks for this but I have to follow this method in which KI ,acetic acids and starch are used