There’s nothing better than finally getting to the summer season, with the promise of chilling by the pool. Many people love swimming in the water in order to deal with the heat and enjoy some fun in the sun.
But here’s the thing about pools, they aren’t magically ready at the beginning of the summer season. During the winter, pools are closed off, left to be covered or even emptied.
When the summer season comes around for them to be open once again, they need to be properly prepared so that they are clean and safe in order to be used by people.
One of the most important parts of preparing a pool for reopening is shocking it, and once it has been shocked, you need to wait for a certain amount of time before it’s safe for the pool to be used. Some swimming pools will need pool shock multiple times throughout the season as well.
How long do you have to wait? Why do you have to wait? What is pool shock?
Let’s get right into it!
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What Does Shocking A Pool Mean?
Before we answer the main question, it’s worth explaining and clarifying what shocking a pool actually means, because no, it doesn’t mean giving it an electrical shock, that would definitely be dangerous!
Shocking a pool is the process of adding chemicals, such as conveniently labeled “pool shock” to it so that the water composition is prepped and ready for chlorine or other cleaning methods.
It is essentially a big jump-start to the cleanliness of the pool so that the water is completely hygienic and safe. As the pool will have accumulated a lot of dirt and bacteria over the winter season, this is absolutely crucial before reopening!
What shocking the pool does, is raise the levels of free chlorine so that algae and bacteria are eliminated, and the water becomes cleaner.
Many different types of chemicals can be used during this process, some of them stronger than others for when the pool is in a more serious need of being cleaned.
Some of the main chemicals used during this process are calcium hypochlorite, lithium hypochlorite, dichlor, and potassium peroxymonosulfate.
How Long After Shocking Is A Pool Totally Safe To Swim In?
Once you have shocked the pool by adding all of the necessary chemicals, you need to wait for a certain amount of time, while they do their job and eliminate all of the bacteria.
It would be unsafe to use the pool while the chemicals are in there and working, as they are mostly dangerous and unsafe to come into contact with, let alone swim in them!
The exact amount of time that you have to wait for before the pool is safe will vary according to the size of the pool, the chemicals used, and the number of chemicals used.
However, as a general rule, you should allow for at least 24 hours after shocking the pool, before it is safe to be used by anyone.
After the 24 hours have gone by, you should first test the pool, so that you can be 100% sure that the water is safe to go into.
This is because sometimes the chemicals can take more than 24 hours.
Make sure the pH levels of the water are tested, along with the chlorine levels. If they are within a safe and correct range, then the pool is safe to be used and can be reopened to yourself or the public.
What Happens If You go Into The Pool Too Soon After It Being Shocked?
It is very important that you allow for at least 24 hours after shocking a pool before you can safely use it.
But what happens if you somehow lose track of the time, and you get into the pool too soon? What are the consequences?
The symptoms would be similar to if you are swimming in a pool with too high a level of chlorine.
The chlorine turns the pH of the water acidic, and this can cause some serious irritation, along with other things.
Here are the main symptoms you could suffer:
- Irritation of the skin, with skin rashes and red bumps
- Irritation of the eyes, with your eyes turning red
- Difficulty breathing, due to the vapors of the chlorine and chemicals. This could result in an asthma attack or similar.
You could also get more serious symptoms such as the following:
- Nausea and dizziness
- Vomiting and an upset stomach, especially if you accidentally swallow any of the water with the chemicals
- Coughing and a burning sensation in the throat, due to all the irritation that the water and vapors would cause
- Pain in the chest
- Wheezing and difficulty breathing
- An overall feeling of illness and being unwell
With the milder symptoms, they will usually go away by themselves after a few days. Just make sure to stay away from the pool, drink plenty of water, and have some rest. With some of the more serious symptoms, however, you might have to contact the doctor, especially if they persist and don’t go away after the first couple of days.
If you notice any of the symptoms you should of course get away from the pool, and stop anyone else from going into it, as it isn’t safe for being used.
You might also have to re-start the shocking process, as going in the pool can alter the chlorine levels and the pH levels of the water, due to the new bacteria you will have introduced by swimming in it.
So, to sum it up, shocking a swimming pool is the process of adding chemicals so that the water can be cleaned, and all bacteria and algae are eliminated. It essentially makes the pool safe for use.
However, while the chemicals are doing their thing, it is not safe to use the pool, and you will get several different symptoms such as irritation, due to the acidic pH levels.
*Check Out Our List Of Chemicals For Above Ground Pool Maintenance.
As a general rule, you should wait at least 24 hours after shocking a pool, also known as adding cleaning chemicals to your pool, before it is safe to be used.
My name is Denise and I am an Analytical Chemist located in the Kansas City metro area. Some things I am passionate about are gardening, science, swimming, and blogging. I am happy to be part of the All About Pools team & contribute my knowledge & expertise to help swimming pool owners and backyard enthusiasts!