Engine: General Subjects

1. A Disinfection is not required on biological sewage treatment plants.
2. B Ultraviolet light irradiation is the only approved means of disinfection.
3. C Hypochlorite tablets or liquid solution and ultraviolet irradiation are both approved means of disinfection.
4. D Hypochlorite tablets or liquid solution is the only approved means of disinfection.

Tip: press A-D to answer