Why do swimming pools need chlorine?
Swimming is an aerobic activity that gives us a whole-body exercise without much effort. Being a non-impact workout, this aqua activity is very gentle on the joints. This summertime fun activity is loved by kids and adults alike. All of us know that swimming pools have to be disinfected regularly by adding chlorine to the water. However, many of us don’t know why this chemical is needed in a pool.
Pool water gets contaminated
Swimmers can cause many pollutants and germs to enter the water through their saliva, sweat, cosmetic lotion residue, excretion products, and more. It, therefore, becomes necessary to sanitize the water to avoid common health problems like diarrhoea, rashes, eczema, ear and eye infections. Chlorine is added to the pool water in order to drive away the germs.
How is chlorine formed?
Chlorine is a naturally occurring chemical element produced from ordinary salt through the process of electrolysis. In this process, electric current is passed through a solution of brine, a common salt dissolved in water. This leads to the formation of chlorine.
Types of chlorine
When it comes to pool sanitization, there are three types of chlorine that one needs to know about: Free chlorine, combined chlorine, and total chlorine. Free chlorine is the combination of hypochlorous acid and hypochlorite ion (OCl-) which sanitizes a swimming pool. Chlorine is said to be combined when it mixes directly with the contaminants. Total chlorine is basically the sum total of free chlorine and combined chlorine.
How does chlorine disinfect swimming pools?
When chlorine is added to a swimming pool, it forms a weak form of acid called hypochlorous acid and OCl-. This is what kills bacteria like salmonella and E. coli, as well as germs that cause ear and gastrointestinal infections.
Side effects of chlorine
While the bacteria-killing properties of chlorine are very useful for pool sanitization, this naturally-occurring chemical comes with some annoying or hazardous side effects too:
- It has a distinctive and unpleasant smell. However, some find it overwhelming.
- Chlorine can trigger allergic reactions. It can irritate the skin and make it itchy.
- The hypochlorite ion may cause the colour of the fabrics to fade if it is not rinsed off immediately after getting out of the pool
- High amounts of chlorine can lead to breathing trouble
Alternatives to chlorine
Though chlorine is still the most popular purifying agent used for water treatment and swimming pools, there are some alternatives to it for disinfecting swimming pools. Some of them are bromine, ozone generator and Polyhexamethylenebiguanide or PHMB among others.