Combined Chlorine in Swimming Pools

The term "Combined Chlorine" in regard to swimming pools, also known as chloramines, is the chlorine that has reacted with organic matter and contaminants in the water, making it less effective as a sanitizer.

What is Combined Chlorine?

Combined chlorine forms when free chlorine reacts with substances like sweat, urine, and other organic materials in the pool. It contributes to the strong "chlorine smell" often associated with pools.

Why is Combined Chlorine a Problem?

  • Irritation: Causes red eyes, dry skin, and respiratory irritation.
  • Odor: Responsible for the strong chlorine smell in poorly maintained pools.
  • Reduced Effectiveness: Indicates that free chlorine is being consumed by contaminants, leaving less available for sanitization.

How to Reduce Combined Chlorine

To eliminate combined chlorine, follow these steps:

  1. Test Levels: Use a pool test kit to measure combined chlorine.
  2. Perform Breakpoint Chlorination: Add enough chlorine to raise the free chlorine level by at least 10 times the combined chlorine level.
  3. Improve Circulation: Ensure the pool's filtration and circulation systems are working properly.

Prevention Tips

  • Encourage swimmers to shower before entering the pool to minimize organic contaminants.
  • Regularly test and maintain proper free chlorine levels.
  • Use pool covers to reduce debris and organic material entering the pool.

Related Terms

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