What are the three types of disinfection methods mentioned in drinking water treatment?

What are the three types of disinfection methods mentioned in drinking water treatment?

• A. Boiling, Filtration, Chemical
• B. Heat, Radiant, Chemical
• C. Physical, Chemical, Biological
• D. Chlorination, Ozonation, Distillation

Answer: (C)

Disinfection in drinking water is commonly classified into three broad categories: physical, chemical, and biological methods. Physical disinfection uses energy input to inactivate microbes without adding chemical agents—examples include heat (such as boiling) and ultraviolet (UV) light. Chemical disinfection relies on chemical agents that kill or inactivate microorganisms, like chlorine, chloramines, chlorine dioxide, and ozone, and these chemicals also help maintain a residual disinfectant in the distribution system. Biological disinfection depends on natural or engineered biological processes to reduce or inactivate pathogens, such as biofiltration or other treatment steps that use microbial activity to suppress contaminants. This threefold framework is what’s typically referenced because it covers the main ways water treatment systems achieve disinfection. Other groupings often mix removal steps or focus on specific techniques rather than the broad categories.

Disinfection in drinking water is commonly classified into three broad categories: physical, chemical, and biological methods. Physical disinfection uses energy input to inactivate microbes without adding chemical agents—examples include heat (such as boiling) and ultraviolet (UV) light. Chemical disinfection relies on chemical agents that kill or inactivate microorganisms, like chlorine, chloramines, chlorine dioxide, and ozone, and these chemicals also help maintain a residual disinfectant in the distribution system. Biological disinfection depends on natural or engineered biological processes to reduce or inactivate pathogens, such as biofiltration or other treatment steps that use microbial activity to suppress contaminants. This threefold framework is what’s typically referenced because it covers the main ways water treatment systems achieve disinfection. Other groupings often mix removal steps or focus on specific techniques rather than the broad categories.