Course Objective: To teach learners about disinfectants and disinfection including mathematics of chlorination and how chlorine inactivates pathogenic organisms using the CT concept.

This course, part of the Water Treatment Fundamentals bundle, focuses on disinfection. 4 Contact Hours (or 0.4 CEUs) will be granted upon completion of this course.

Disclosure: None

Upon completion of this course, learners will be able to:


✓ common chlorine compounds used for disinfection

✓ properties of chlorine gas

✓ safety equipment used in handling chlorine gas


✓ disinfection

✓ log removal requirements for conventional treatment


✓ disinfectant byproduct formation

✓ disinfection residual requirements


✓ equipment and appurtenances for feeding chlorine gas

✓ chlorine chemistry

✓ chloramine chemistry

✓ breakpoint chlorination chemistry

✓ the procedure to estimate acceptable chlorine residual levels to meet CT and minimize THM formation


✓ log removal value and percent removal

✓ disinfectant dosage

✓ available disinfectant concentration

✓ chlorine demand and chlorine residual

✓ CT value


✓ disinfectant byproduct reduction procedures


✓ safety precautions in handling chlorine cylinders


✓ effectiveness of different disinfectants in meeting CT requirements

A. Log inactivation or Log Removal     

1. Relationship between Log Removal and Percent Removal     

B. Log Removal Requirements for Conventional Water Treatment     

1. SWTR/IESWTR Log Removal Requirements     

C. Determining CT Compliance for Chlorine Disinfection     

1. Calculation of CT Ratio     

D. Chlorine Chemistry     

1. Chlorine Gas     

2. Hypochlorite     

3. Control Tests     

E. Properties of chlorine gas     

F. Safety precautions in handling chlorine gas cylinders     

1. Safety precautions in handling 150 lb cylinders     

2. Safety precautions in handling ton (2,000 lb) cylinders     

G. Equipment and Appurtenances for Feeding Chlorine Gas     

H. Safety Equipment     

    1. Proper Safety procedures     

I. Chloramination     

J. Breakpoint chlorination   

K. Computations: Mathematics of Chlorination     


About Instructor

Water Treatment Instructor

This instructor has over twenty-five years of experience in the water industry. He was also a college adjunct instructor teaching water treatment classes.

Not Enrolled
From $15

Course Includes

  • 1 Lesson
  • 12 Topics
  • 1 Quiz
  • Course Certificate