For many people, the first thought when they think of swimming pools is the familiar smell of chlorine. However, chlorine as a disinfectant in bath water is odorless.
The typical indoor pool smell does not come from chlorine directly, but from chlorine compounds with already bound chlorine, the chloramines.
Chloramines arise mainly from the reaction of the chlorine contained in the water with nitrogen compounds.
These nitrogen compounds include, for example, urea, creatinine and other amino acids. The majority of these substances get into the water through urine, sweat and through the skin.

The reaction of chlorine with urea added to the water creates the familiar swimming pool smell.
Chloramines are also the cause of irritated, red eyes, especially known by frequent swimmers.

Although most of the urea reaches the swimming pool via urine, a substantial part of it comes from the skin surface of the bathers.
This proportion can be reduced significantly by showering before entering the swimming pool.