Improving experimental methods for hygienic assessment of the use of metallic materials and their alloys in drinking water supply systems

Abstract

Introduction. For many years, steel and cast iron pipes have been used in the practice of domestic drinking water supply. However, they can be a source of pollutants entering drinking water. During the hygienic assessment, special attention is paid to metal impurities in corrosion products, which under certain conditions can enter drinking water distribution systems, thereby polluting drinking water and creating a health risk. Materials and methods. The material was scientific reports and laboratory studies on the problem of the use of metal materials and their alloys in drinking water supply systems, with special attention to the specific properties of the analyzed materials. Results. The objective of our research is an attempt to standardize hygienic studies of metal materials (alloys) used in drinking water supply. The object developed was a research laboratory stand that recreates the conditions of a real water supply system, which makes it possible to simulate operating conditions for sanitary and chemical testing of metals and alloys intended for use in contact with drinking water. The stand guarantees a continuous flow of water through the tested material, simultaneous testing of the required number of samples, including control ones, as well as connection to cold and hot water supply systems (with test temperatures from 60 °C to 85 °C). It also allows temporarily stopping the flow of water to simulate standing water (test lines are closed for four hours before sampling), collect at least 3 liters of contact water for further testing, and also makes it easy to install the system and replace test samples. Limitations. Modelling of operating conditions for sanitary and chemical testing was carried out on metal materials (alloys), which are one of the possible options for using materials in drinking water supply. It is necessary to conduct similar studies on other groups of materials used. Conclusion. This stand can be used by laboratories to carry out sanitary-chemical analysis of alloys that are used in drinking water supply systems. The developed methodology makes it possible to improve the quality and accuracy of the analysis of metallic materials and alloys through the use of a unified research system.