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Upgrade nowNon-Mechanical Backflow Devices
Read through the material below, then test your understanding.
Module Lessons
Cold Water Systems: Planning & Design
Water Industry Legislation
Notification, Part G & Certification
Multi-Storey Boosting Systems
Large-Scale Cisterns: Design & Materials
Cistern Filling & Control Components
Private Water Supplies: Sources & Storage
Private Water Treatment & Disinfection
Private Supply Pumping
Specialist Cold Water Taps
Shower Pumps & Pressure Control
Fluid Categories & Contamination Risk
Backflow Protection Strategies
Non-Mechanical Backflow Devices
Mechanical Backflow Devices
Backflow Regulations & Guidance
Design Information Sources
Assessing Demand: Flow Rate & Pressure
Pipe Sizing: The Tabular Method
Pipe Sizing: BS EN 806 & Thomas Box Formula
Cistern Capacity & Pump Power Calculations
Accumulator Sizing & Presenting Designs
Fault Diagnosis: Booster Pumps & Backflow Devices
Corrosion Faults: Electrolytic & Blue Water
Commissioning Standards & Regulations
Soundness Testing: Planning & Preparation
Disinfection: Types, Process & Capacity
Disinfection: Testing & Flushing
Commissioning Records, Defects & Certification
Maintenance Types & Legionella Control
Lesson Overview
Non-mechanical backflow arrangements use physical air gaps or atmospheric vents to prevent backflow and back siphonage without moving components. They provide the highest reliability across all fluid categories.
Learning Objectives
Identify the classifications, configurations, and fluid category ratings of non-mechanical backflow devices.
Calculate minimum vertical air gap dimensions for domestic and commercial sanitary tapware and cisterns.
Specify installation rules for pipe interrupters and specialised weir air gaps under the Water Regulations.
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