Human health directly depends on the quality of drinking water. In this regard, the requirements for drinking water quality when designing drinking water treatment facilities are considered basic data. The quality of drinking water must meet the requirements of state standard 2874-82 “Drinking water”. The main indicators of water quality include turbidity, color, smell and taste of water, hardness, alkalinity, oxidation, amount of dry residue and various chemicals, total number of bacteria, coli titer, coli index. Turbidity is the amount of suspended solids in water. According to the standard, the turbidity of drinking water should not exceed 1.5 mg/l. The color of the water is due to the presence of dyes, algae and fulvic acids in the water. The color of drinking water should not be higher than 20 degrees on the platinum and cobalt scale. The taste and smell of drinking water should not exceed 2 points on a five-point scale at a water temperature of +20°C. An active reaction indicates the degree of alkalinity or acidity of water, which is characterized by the concentration of hydrogen ions. According to the standard, the pH of drinking water should be between 6 and 9.

Water hardness indicates the amount of dissolved calcium and magnesium salts. The limit value of the total hardness of drinking water should not exceed 7.0 mEq/l, in special cases up to 10 mEq/l is allowed. Oxidation indicates the amount of organic and some rapidly oxidizing inorganic substances dissolved in water. Although the standard does not require this indicator, a high degree of oxidation of water indicates its contamination with tap water. The dry residue indicates the total amount of salts dissolved in water. The dry residue of drinking water should not exceed 1000 mg/l. Taking into account the amount of various chemicals in drinking water, the amount of total iron should not exceed 0.3 mg/l. The amount of manganese should not exceed 0.1 mg/l. The amount of chlorides should not exceed 350 mg/l, sulfates - 500 mg/l. The amount of copper should not exceed 1.0 mg/l, zinc - up to 5.0 mg/l, lead - up to 0.03 mg/l, arsenic - up to 0.05 mg/l, beryllium - up to 0.0002 mg/l l, selenium - up to 0.001 mg/l, nitrates - up to 45.0 mg/l. And the amount of fluorine ranges from 0.7 to 1.5 mg/l depending on the climate. The total number of bacteria in drinking water should not exceed 100 per ml. Coli titer is the volume of water in cm3 containing one E. coli. The coli titer should not be less than 300. The coli index is the amount of E. coli in 1 liter of water; the coli index should not exceed 3 in drinking water. Modern hygienic science places strict demands on the sources that supply the country with water. Previously, it was believed that it was enough to purify water once. However, despite the enormous capabilities of purification technology, even the presence of well-equipped filter stations and their impeccable use, it is from these sources that stomach diseases are spreading throughout the country. Therefore, attention is paid to various methods of purification and neutralization of drinking water, sanitary and hygienic measures to protect water sources. Remember that cleanliness is the key to health.

RK "USO" RMK Ministry of Education and Culture of the Republic of Kazakhstan

branch in Atyrau region

Makat district branch

heads of G. T. Erdybaev