How to Test for Chlorine in Drinking Water

Chlorine is added to drinking water at the processing plant to kill bacteria and germs before it reaches your faucet. While chlorine is also used for the same reason when added to pool water, it is important that the levels are not to high or it could cause eye irritation. You can test the levels of chlorine yourself using an over-the-counter testing kit.

Things You'll Need

• Othotolidine (OTO) chlorine test kit

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Instructions

• 1

  Fill the testing vial up to the specified line with the water you want to test. Refer to the testing kit's instructional manual to determine how much water should be added, since amounts may vary based on manufacturer.

• 2

  Add five drops of OTO solution to the vial filled with water. Check with the instructional manual for your OTO testing kit to verify the amount of solution that is to be used. Amounts required for an accurate test may vary, depending on brand.

• 3

  Watch the water's color change to yellow. The darker the shade it turns to, the more chlorine is present in the water. The water will turn brown if their are excessively high amounts of chlorine in the water you are testing. Read the instructional manual's color comparison chart, which depicts the levels of chlorine based on the color from the test. Compare the water's color to the chart to determine if the pool water's chlorine level is around 1.0 - 2.0 ppm, which is the recommended amount.