Kit for Detection of Residual Chlorine in Water

Measuring residual chlorine in water

Types of chlorine in water

Whenever you inject chlorine into the water, the chlorine begins to oxidize the substances and organisms in the water.

This oxidizing or burning of pollution causes the consumption of chlorine, but this consumption does not mean the destruction of chlorine (at least at this stage). Rather, chlorine turns into chloramine after completing its task. This chloramine no longer has the properties of oxidation and disinfection. And it only causes eye irritation, skin itching and other side effects.

Active and oxidizing chlorine is called free chlorine.

So we need to know which chlorine is in the water and how much. It can be detected by the water chlorine test method that we are talking about here.

Now that we understand what type of chlorine we should look for in water and what form of chlorine is useful for us, we should find the right way to measure chlorine.

Types of water chlorine testing methods

Different chlorine testers can be used to detect the level of chlorine in water (this water may be drinking water or swimming pool water).

Types of chlorine tester

Electronic chlorine tester
Chemical chlorine tester

Electronic chlorine tester

In the electronic chlorine tester, the amount of chlorine is obtained by measuring some water parameters such as PH, TDS, etc.
So it can be concluded that due to the lack of direct measurement of chlorine by electronic method, the accuracy of these chlorine testers is low, except for high-quality and accurate types, which are usually very expensive.

Of course, these testers can be used to measure pool water, which does not require accurate measurement.
However, it is not recommended to measure the chlorine in drinking water unless they are approved samples with a world-renowned brand.

These testers usually show the total chlorine in the water. It means the sum of free chlorine and chloramine

Chemical chlorine tester

In the chemical chlorine test kit, chemicals are used as reagents for water chlorine level.

The chlorine meter kit is a suitable tool for measuring water health and the amount of chlorine in it. The method of measuring the amount of chlorine in water is expressed based on the color change. That is, by adding a specific amount of these materials to a specific amount of water and changing the color of the solution left behind, you can estimate the level of chlorine.

According to the sensitivity of chlorinometer kits, they can be used to check drinking water or swimming pools.

The concentration of chlorine in urban water sources is in the range of 0.1 to 0.6 parts per million, while the amount of this concentration in swimming pools is about 1 to 3 ppm.

The water chlorine test method with chemical reagents is indicated by two chemicals: Orthotolidine, which is abbreviated as OTO, and N,N-diethyl-p-phenylenediamine, which is abbreviated as DPD.

OTO or orthotolidene chlorine meter

OTO is a substance that will turn yellow in the presence of chlorine in water.
The higher the amount of chlorine, the yellow color of the solution becomes more intense and finally turns into orange color.

DPD chlorine meter

DPD is sold in the form of powder, tablet or liquid, and it will turn pink or red when mixed with pool water.
A very high level of chlorine (above 30 PPM) makes the DPD color clear and creates the illusion that chlorine is not present.

Normally we would not achieve this level of chlorine. But this is always expressed as a weakness of DPD.

Comparison of chlorine test kit OTO and DPD:

With the DPD method, free or active chlorine can be measured, that is, the chlorine that is important to us.
Of course, some articles state that free chlorine can be measured with the OTO test, but this should be done in less than 10 seconds.

In other words, within 10 seconds after entering the OTO solution into the tested water container, the amount of free chlorine can be observed. After this time, the yellow color of the solution indicates the total chlorine in the water.

Of course, the weak point of OTO solution does not end here, and the presence of substances such as iron and manganese, etc., will cause this reagent to go wrong. Also, ortholidene has toxic and carcinogenic effects.

So, due to the same cost of preparing these chlorine test kits, we suggest DPD chlorine test kit.

Asaish Afza Ayman Company produces various types of chlorination kit using DPD single drop method, chlorination kit using DPD powder method, single drop hardness test kit, double DPD and PH kit.

Advantages of using DPD drops and colorimeter kit of Asaish Afza Ayman company:

Asaish Afza Ayman’s colorimeter kit has approval.
DPD solution of Asaish Afza Company is a single drop.
Compared to the use of tablets or other solutions (to use other solutions, two solutions number 1 and 2 should be used) it is economical.
It is easy for the user to use.
High accuracy