The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about______________? January 17, 2019 – by admin The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about______________? A. 0.01 to 0.05 ppm B. 0.05 to 0.5 ppm(Correct) C. 0.5 to 1.0 ppm D. 1.0 to 5.0 ppm
The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about______________? A. 0.01 to 0.05 ppm B. 0.05 to 0.5 ppm(Correct) C. 0.5 to 1.0 ppm D. 1.0 to 5.0 ppm