There is confusion about what exactly causes someone’s eyes to burn when swimming in a pool. Most people believe that if their eyes are burning while swimming in a pool, then it is due to the chlorine in the pool. In reality, there are two more common reasons that can cause eye irritation when swimming in a pool.
The first reason for eye discomfort is due to the pH of the water in the swimming pool. The acceptable ranges for pH, as regulated by each State Department of Health, falls within 7.2 to 7.8 range. These ranges are important for several reasons. When the water is within this pH range, then the water is in balance and it has a less detrimental impact on the pool and the pool equipment. Most importantly, when the pH is within this range and balanced it is more comfortable for the swimmer’s eyes. The reason for this is because the pH of the human eye is 7.4. Therefore whenever the pH range is either low (more acidic water) or high (more basic water) then this typically causes discomfort to the human eye. This principle is similar to balancing the pH in baby shampoos to protect the baby’s eyes during bathing.
The second reason for eye discomfort is due to the lack of chlorine. Combined chlorine is what happens when chlorine is being locked up by organic waste and is rendered useless in the swimming pool. When this happens, chloramines are produced, which has a distinct odor similar to the smell of chlorine. These chloramines also cause eye irritation. The next step to eliminate this problem is by simply adding more chlorine to the water. The goal is to reach breakpoint chlorination by adding the necessary dosage of chlorine to eliminate the combined chlorine in the water so that the free chlorine can effectively do its job and sanitize the water properly.
Of course, when the chlorine levels are too high, this can cause “bleaching” of swimsuits and skin, as well as eye irritation. To assure proper water chemistry with your swimming pool, it is recommended that you contact your local ASP - America's Swimming Pool Company professional for further information on properly maintaining your swimming pool. If you don’t know which ASP location is closest to you, click over to our locations page, where we have each of our locations listed.