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Upgrade nowMechanical Backflow Prevention Valves
Read through the material below, then test your understanding.
Module Lessons
Cold Water
Incoming Mains: Communication vs. Supply Pipes
Installation Depths and Building Entry
Direct Cold Water Systems
Indirect Cold Water Systems
Siting and Installing Storage Cisterns
Float-Operated Valves and Overflows
Principles of Backflow
Terminal Fittings and Taps
Non-Mechanical Backflow Prevention (Air Gaps)
Water Treatment and Distribution
Mechanical Backflow Prevention Valves
Commissioning: Testing and Flushing
Lesson Overview
Mechanical backflow prevention valves provide a physical barrier to stop contaminated water from flowing backwards into wholesome drinking supplies. Selecting and installing the correct valve according to the fluid category risk is essential for meeting the Water Regulations.
Learning Objectives
Identify the mechanical backflow prevention valves used across fluid categories 2, 3, and 4.
Explain the key operational differences between verifiable and non-verifiable check valves.
Apply correct positioning and installation requirements for mechanical backflow devices in domestic systems.
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