How Long After Adding Chlorine Can I Swim (And Why)?

Exact Answer: 2-4 hours

Chlorine-type chemicals are most commonly used in pools for sanitation. The water could be contaminated due to various reasons either by human beings or through any environmental process.  Few people believe that the addition of chlorine to the pool may increase the risk of swimmers but it is necessary to add chlorine to prevent illnesses related to waterborne such as diarrhea and other skin infections. 

Usually, chlorine is added either after swimming or in the evening, which will allow the chlorine to spread uniformly throughout the pool. It is also mandatory to filter the water after adding chlorine. If you do not add chlorine, the water may turn cloudy leading to a fertile environment.

How Long After Adding Chlorine Can I Swim

How Long After Adding Chlorine Can I Swim?

Chlorine, a commonly known pesticide can be added either in the form of liquid or solid which ensures to kill the germs available in the pool and also those which are included from saliva, feces, or other substances. But, it is recommended to take extra care while adding chlorine as an excess amount of chlorine could lead to rashes, skin infections, irritation in the eyes, and throat pain.

Generally, it is advised to wait nearly 20 minutes in case of adding other water balancing chemicals, whereas, in the case of chlorine, it is safer to wait for almost 4 hours. This also depends on the size of the pool and the amount of chlorine added. The chlorine level in the pool should be below 5 ppm to avoid any type of risk involved. In few areas, swimmers are not allowed until one complete turnover of the water. 

There are other treatments like shocking a pool which requires more amount of chlorine than usual, which will take a longer period to filter out the chlorine. Shocking treatment is required only when the pool contains algal blooms. In case of a more serious condition, the longer you have to wait to swim. It is a good practice shock to the pool either in the evening or at night without any sun rays. 

If non-chlorine shock treatment has been used, the pool can be used immediately after the shocking treatment. This treatment should be carried out once in 2 weeks. In the case of chlorine tablets, you can swim even in presence of tablets in water. Before proceeding to swim, test the chlorine level with the help of any kit.

Type of ChemicalTime to wait
pH, Alkalinity, Clarifier20 minutes
Calcium Chloride2-4 hours
Muriatic Acid30 minutes
Liquid Chlorine4 hours

Why I Have To Wait That Long To Swim After Adding Chlorine?

One of the best methods to follow is chlorinating the pool to prevent it from algae blooms.  Shocking pool with chlorine is the best choice for serious conditions where four times, the usual amount of chlorine should be used.  It is mandatory to avoid using the pool in case of chlorinating it. It is necessary to wait as the chemical may cause a reaction that leads to the creation of a hot spot.

Few chemicals like Granular and Dicholr chlorine have a high concentration of ions which make swimmers uncomfortable to swim and also have high effects on the eye. Chlorine makes things hard and dry. If you drink the water unknowingly, it may lead to risky diseases and creates heavy digestive problems, especially among children. There is a high probability of issues like nausea, cramps, diarrhea, and aches.

You may take few immediate steps like drinking an excessive amount of water to balance the chemicals in your body and to avoid the risky situation. In case of less concentration of chlorine, the severity will be probably less. When the level of chlorine is reached below 5ppm, it is easier to maintain the level by adding chlorine tablets which do not seem to be risky. 

The dangerous level depends on how much time you have been in the pool immediately after the chlorine treatment.  When the pool is not in much use, make sure the quality of water every week with the help of an appropriate tester.  Also, it is preferred to add one chlorine tablet per skimmer.


There are various methods preferred to clean and maintain the pool periodically especially in busy areas. It is a good choice to chlorinate the pool regularly but ensure to follow the proper instructions to be on the safer side. A standard amount of chlorine is chosen for the safety of humans.

An excess amount of chlorine does not even destroy the germs completely due to high concentration.  The swimmers should be aware of safety tips to avoid risky situations. Vacuum your pool once a week and brush it daily to prevent it from unwanted microbes. Always ensure the pH level of the pool’s water.


One request?

I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️