Chlorine gas sensors applied to detect CL2 leaks in a water treatment plant

Chlorine disinfection of tap water is a common water safety detection method in the world. Chlorine disinfection can effectively eliminate harmful substances in water, and because the cost of chlorine gas is very low, it is recognized as one of the efficient and reliable tap water detection methods in the world. However, with the continuous progress of modern science, some scientists have proposed that the tap water tested with chlorine gas may contain carcinogens, which has caused ordinary consumers to lose confidence in the quality of tap water. But some experts believe that reasonable use of chlorine detection will not produce toxic substances, and can greatly reduce the cost of tap water detection, thereby reducing the price of tap water for residents in our country. So, does chlorine disinfection of tap water have any harm to our human body?

Before understanding whether chlorine gas in tap water is harmful to our human body, we should first understand the main principle of chlorine disinfection of tap water: The main principle of chlorine gas detection in tap water is to use a chlorine dioxide generator to generate chlorine gas. Chlorine gas is easily soluble in water, and reacts with water to produce hypochlorous acid and hydrochloric acid. The hypochlorous acid produced can effectively detect microorganisms and pathogens in tap water. The effect of using a chlorine dioxide generator to detect tap water is better and more acceptable to people than the traditional bleach powder detection method.

So, does chlorine gas have any harm to our human body?

Firstly, chlorine gas itself does have certain harm to our human body. It can irritate our eyes, nose, throat and other organs. Acute pulmonary edema or pneumonia can occur when chlorine gas reaches a certain dose, which can cause serious harm or even death to our body.

However, the residual concentration of chlorine elements used for tap water disinfection in China’s water treatment plants is much lower than the dose that can cause damage to our human body. At the same time, as a volatile chemical substance, chlorine gas starts to dissipate during the storage process of tap water. The modern lifestyle of residents also determines that chlorine gas will not harm our human body. Because the living habits of Chinese residents are often to heat up tap water before drinking it, and during the boiling process, the chlorine gas in tap water has already evaporated. The remaining part of chlorine gas residue, even if it enters our body, will be excreted from the body with metabolism, and will not cause harm to our body, let alone cause cancer. Therefore, it is recommended to avoid direct drinking of raw tap water and try to boil it before drinking, in order to improve the safety of tap water.

 Why can chlorine gas be used to detect tap water?

Tap water is drawn from rivers, lakes, and seas into water treatment plants, and after a series of processes such as coagulation, sedimentation, filtration, and testing, it is input into the tap water pipeline by a high-pressure water pump and delivered to households. Tap water is purified and treated water that meets certain standards for daily life and production, and is a necessary guarantee for people’s basic daily survival. The detection of tap water directly affects water safety, and further affects the health and safety of every user. There are many methods for detecting tap water, and most tap water treatment plants in China currently use chlorine gas for detection.

The chlorine gas detection method has been used for almost 100 years because of its unique advantages. Chlorine gas detection has good effect and can achieve good detection effect at low concentration, and has almost no harm to human body. Moreover, its cost is relatively low, and its process technology is mature and reliable. After chlorine gas is introduced into the water (chlorine dosage during detection) (liquid chlorine is between 1.0-2.5g/m3, which is strictly regulated in the national standard), it reacts with water to generate hypochlorous acid, which has strong oxidizing properties.

   So far, chlorine gas detection is still a mature and widely used water detection technology, and there is no tap water detection method that can completely replace chlorine gas. In fact, there were dozens of detection methods earlier, such as bleach powder and iodine, but chemical detection is a double-edged sword and inevitably produces certain side effects. Therefore, from the perspective of tap water detection safety, the chlorine gas detection method is better.

Chlorine gas is a toxic gas, yellow-green in color, and has a strong irritating odor that can cause sneezing, coughing, endless tears, suffocation, and other symptoms. It mainly enters the human body through the respiratory tract and dissolves in the water in the mucous membrane to generate hypochlorous acid and hydrochloric acid, causing damage to the respiratory mucous membrane. Hypochlorous acid causes strong oxidation of tissues, and hydrochloric acid stimulates mucous membrane inflammation and swelling, causing respiratory mucous membrane edema, secretion of large amounts of mucus, and causing breathing difficulties. Therefore, the obvious symptom of chlorine gas poisoning is severe coughing. When the symptoms are severe, pulmonary edema occurs, which can lead to death.

For things such as algae in water, the strong oxidation of hypochlorous acid can destroy their cell walls, oxidize their enzymes, and cut off their protein synthesis, which can cause their death and achieve the purpose of detection. However, since hypochlorous acid has a negative charge, the detection effect is not ideal, so chlorine gas is used instead of bleach powder for detection.

However, it is important to be cautious about the amount of chlorine gas used for detection, as chlorine gas is a toxic gas that mainly enters the human body through breathing and dissolves in the water in the mucous membrane to generate hypochlorous acid and hydrochloric acid, causing damage to the upper respiratory mucous membrane. Hypochlorous acid causes strong oxidation of tissues; hydrochloric acid stimulates mucous membrane inflammation and swelling, respiratory mucous membrane edema, secretion of large amounts of mucus, and breathing difficulties. Therefore, the obvious symptom of chlorine gas poisoning is severe coughing. When the symptoms are severe, pulmonary edema occurs, making circulation difficult and causing death. Therefore, when using the chlorine gas detection method, it is necessary to monitor the chlorine gas content. In response to this problem, the Songbai S4-CL2 chlorine gas sensor can effectively address this issue by detecting whether the chlorine gas content exceeds the set range, and allowing relevant personnel to make timely adjustments.

Chlorine gas sensors used for tap water detection have greatly improved the quality of human life and reduced the occurrence of some discomfort. Compared to ozone, chlorine gas has significant advantages, with lower cost and mature technology, which will be beneficial to the daily lives of residents and reduce water prices. Through continuous technological upgrades, better tap water detection solutions will continue to emerge.