How is titration used in swimming pools?

Titration test: This test utilizes reagents (chemicals) that are dropped into the water sample and cause a change in color. The variable here is not the hue of the color, but rather the number of drops needed to change the color. Each drop correlates to a specific level of the factor being tested.

How do I measure the chlorine in my pool?

Pool chlorine levels are easily measured by dipping a test strip in the pool for a few seconds and then matching the resulting color of the strip to a chart linked to “parts per million” chlorine levels.

How do you calculate free chlorine level?

The formula of chlorine is free chlorine + combined chlorine = total chlorine.

How do you balance free chlorine and total chlorine?

What should I do if total chlorine is higher than free chlorine? If total chlorine is higher than free chlorine, there are contaminants in the pool. Subtract the free chlorine measurement from the total chlorine measurement to calculate the amount of combined chlorine (total – free = combined).

Why is there no free chlorine in my pool?

Chlorine lock can occur when there is too much cyanuric acid (also referred to as conditioner or stabilizer) in the water. This occurs when too much stabilizer is added to the water or when the swimming pool isn’t being partially drained and refilled periodically. Chlorine lock can also occur if the pH is unbalanced.

What pool chemicals contain cyanuric acid?

Many chlorine products, like trichlor or dichlor granules or tablets, already include cyanuric acid. These are known as stabilized chlorine products. So every time you add chlorine to your pool, you’re adding CYA. On the other hand, unstabilized chlorine, like liquid chlorine, does not contain cyanuric acid.

How do you read Free chlorine strips?

Dip your strip into a glass of water (not your sampling container!) and move it back and forth for 30 seconds. Alternatively you can hold it under a stream of water for 10 seconds. The pads will change color to indicate Total Chlorine (white pad on end) and Free Chlorine (yellow pad).

What is DPD method for free chlorine?

A method of measuring the chlorine residual in water. The residual may be determined by either titrating or comparing a developed color with color standards. DPD stands for N,N-diethyl-p-phenylenediamine.

How is free residual chlorine calculated?

These colorimeters use the following method: 1) addition of DPD tablets or powder into a vial of sample water that causes a color change to pink; and, 2) insertion of the vial into a meter that reads the intensity of the color change by emitting a wavelength of light and automatically determining and displaying the …

How do you titrate chlorine?

The excess thiosulfate is then titrated with a standard iodate solution to its endpoint. The chlorine residual can be calculated by subtracting the amount of iodate solution used from the amount of thiosulfate solution added originally. (This gives you the amount of thiosulfate solution that reacted with the chlorine.

Where does free chlorine come from?

When you add chlorine to your pool, it dissolves and forms hypochlorous acid (HOCI). This weak acid then further dissociates in the water, combines with oxygen, and forms hypochlorite (CIO), an oxidizing ion, and the active ingredient in household bleach. Together, these chemicals form free chlorine.