Book excerpt: Experience has shown that when maintenance operators can understand and properly use blueprints and schematics they have little difficulty in correctly interpreting and using plant unit process drawings. Blueprint Reading bridges the gap between available training materials and the information water and wastewater maintenance operators need to know. It covers basic principles of blueprint reading and deals with principles and applications of schematics and symbols. Each chapter presents essential, practical knowledge vital to understanding and interpreting plant operations and that enhances the reader's ability to properly maintain plant systems.