Water and Wastewater Disinfection
Course Pack: Treatment Foundations
Chemical Strength Never Changes
Course Description
This module provides a technical review of chlorine and hypochlorite
disinfectants, including differences in physical form, stability, and operational behavior. Learners
learn how decay mechanisms influence dose reliability, residual control, and system
performance. The module also covers safety, storage, and field-verification practices required for
compliant chemical-strength measurement.
Learning Objectives
1) Differentiate common chlorine/hypochlorite forms used for disinfection
2) Explain decay-rate drivers and how they affect dosing and residual
3) Select handling and safety practices for dry and liquid forms
4) Verify chemical strength using operational measurement concepts
5) Connect disinfectant form choice to equipment and monitoring needs
Agenda
1) Disinfectant forms: gas chlorine, liquid hypochlorite, dry products
2) Dry feeding systems: tablets and equipment considerations
3) Safety focus: hazards, PPE, storage, incompatibilities
4) Chemical decay and strength: what changes and why it matters
5) Strength verification: operational checks and interpretation
Target audience
Water and wastewater operators responsible for monitoring, applying, or evaluating chlorine-based disinfectants.
Level
II
Learning material and method
Online on-demand
Assessment
Knowledge check and quiz (80% correct and above)
Instructor
Mike Harrington