This course is designed to introduce participants to the basic operation of a cooling water system and various types of cooling towers. After completing this course, participants should be able to explain how cooling occurs in a cooling tower and describe the general design and operation of natural-draft and mechanical-draft cooling towers. They should also be able to describe general procedures for shutting down and starting up one cell of a multicell cooling tower. In addition, participants should be able to describe towers, and they should be able to describe the effects of contaminants on cooling water and explain how chemicals can be safely added to cooling water systems.