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En Ok Pool Reform within Water values and specifically in the section on pool chlorine We are going to try to answer:What is the level of the different chlorine values in swimming pools?
What is pool chlorine?
Chlorine is a naturally occurring chemical element and one of the basic components of matter.
How is chlorine in the pool produced?
- Chlorine is produced from common salt by passing an electrical current through a brine solution (common salt dissolved in water) in a process called electrolysis.
Why should we add chlorine to swimming pools?
Chlorine is added to water to kill germs, and this forms a weak acid called hypochlorous acid that kills bacteria (such as salmonella and as well as germs that cause viruses such as diarrhea and swimmer's ear).
Although, chlorine is not the only possibility in the pool water treatment (click and discover the alternatives to chlorine!).
Types of pool chlorine values
There are three main values of chlorine in swimming pools: free chlorine, combined chlorine and total chlorine.
Formation of the different chlorine values
Parts per million (ppm).
A measurement that indicates the parts of a substance, such as chlorine, by weight in relation to one million parts by volume of pool water.
A general rule to follow to maintain good water quality in swimming pools is to keep FAC levels between 2.0 and 4.0 ppm. (see NSPI recommendations table)
Level relationship table of different chlorine values in swimming pools
Existing values within chlorine in swimming pools | Explanation of the different values of chlorine | Ideal chlorine level in swimming pools according to specific value |
---|---|---|
What is free chlorine | There are different chlorine values for swimming pools but the most common is the "free chlorine" value. Free chlorine is the amount of chlorine that is available to kill bacteria and other contaminants. | The free chlorine level in swimming pools is 0,6 – 1,5 ppmpm (parts per million). |
What is combined chlorine | Combined chlorine is the amount of chlorine that binds to contaminants, meaning it has already been used to kill germs and is not available to kill new germs. | Ideal combined pool chlorine level is 0,2 ppm. |
What is total chlorine | Total chlorine is the sum of free and combined chlorine. Actually, the total chlorine value is a good indicator of the quality of the pool but the free chlorine value is the most important to determine safety. | The ideal level of free chlorine in a total pool is 1,2 ppm. |
All chlorinated products used in treatment produce hypochlorous acid (HCLO) when reacting with water.
- Hypochlorous acid is a weak acid that dissociates to hypochlorite (ClO–) in water according to an equilibrium conditioned by the pH value.
- The sum of these 2 forms constitutes what is called free chlorine. In waters with a high pH, most of the hypochlorous acid (active chlorine) is converted to hypochlorite ion (potential chlorine), a form of chlorine with very low disinfectant power.
Ideal pool combined chlorine level
What is combined available chlorine (CAC) or chloramines.
Combined chlorine is the result of the combination of chlorine with ammonia and nitrogenous organic matter contained in water.
- When your pool has a combined chlorine reading, it means that the amount of chlorine present in the water has been reduced. This can be due to several factors, such as evaporation, sun exposure, and swimmers entering the pool.
- Combined chlorine is the result of the combination of chlorine with ammonia and nitrogenous organic matter contained in water.
- The portion of chlorine in water that has reacted and combined with ammonia, nitrogen-containing contaminants, and other organics such as sweat, urine, and other waste from swimmers. Some chloramines can cause eye irritation and chlorine odors.
- Combined chlorine is not harmful for swimming, but may cause eye and skin irritation. If you have a combined chlorine reading on your pool, you should shock the pool to raise the chlorine levels. You can also use a clarifier to help remove impurities that may be causing the problem.
What are chloramines
Chloramines in swimming pools
Chloramines are also known as combined chlorine. Total chlorine is the sum of free chlorine and combined chlorine. The total chlorine level must always be equal to or greater than the free chlorine level.
Level of Combined Available Chlorine (CAC) or chloramines.
How much combined pool chlorine
- Ideal combined pool chlorine level is 0,2 ppm.
Residual combined pool chlorine regulations
- "Residual combined chlorine" is regulated by Royal Decree 742/2013, which establishes a value of ≤ 0,6 Cl2 mg/L and it is indicated that if it exceeds 3 mg/L, the glass must be closed until the value normalizes.
Free chlorine level in swimming pools
free chlorine level in swimming poolsFree available chlorine (FAC).
The sum of chlorine + hypochlorous acid constitutes what is called free chlorine.
Free available chlorine (FAC). Free available chlorine is the most active form of chlorine that kills germs.
What is residual free chlorine
Residual free chlorine is the remainder of the chlorine that remains available in the water, after part of it reacts in the disinfection process.
The presence of free chlorine, from purification to the end of the networks, assures us that drinking water has been properly disinfected.
The portion of total chlorine remaining in chlorinated water that has not reacted with contaminants and is "free" to go to work killing bacteria and other contaminants.
In waters with a high pH, most of the hypochlorous acid (active chlorine) is converted to hypochlorite ion (potential chlorine), a form of chlorine with very low disinfectant power. hypochlorite.
The portion of total chlorine remaining in chlorinated water that has not reacted with contaminants and is “free” to work to kill bacteria and other contaminants. Make sure your test kit can measure FAC; many only test for total chlorine.
Ideal free pool chlorine level
Ideal free chlorine level in swimming pools is 0,6 – 1,5 ppm (parts per million).
- It is the disinfectant and reactive species, it must be kept at its optimal values to achieve disinfected water.
- Ideal levels of residual free chlorine range between 0,6 – 1,5 ppm and residual free bromine range between 2 – 5 ppm in swimming pools and 4 – 6 ppm in spas.
- The World Health Organization establishes free chlorine as indicator parameters between 0,5 and 0,2 milligrams per liter of water.
- Finally, note that if the levels are below 0,2 it will be advisable to add more chlorine.
Total chlorine level in swimming pools
What is total chlorine
Total chlorine is the sum of free available chlorine and combined chlorine.
Total pool chlorine dosage refers to the amount of chlorine needed to achieve a desired level of disinfection and oxidation in a pool.
The sum of free chlorine + combined chlorine constitutes = total chlorine.
- In this way, total chlorine is the sum of free chlorine and combined chlorine results in total chlorine.
- On the other hand, total chlorine should not exceed more than 0,6 mg/l of the free residual chlorine level.