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Upgrade nowAir Admittance Valves (AAVs)
Read through the material below, then test your understanding.
Module Lessons
Advanced Sanitation & Rainwater Systems
Sanitation Legislation: Parts F, G & H
BS EN 12056 & European Drainage System Types
Primary Ventilated Stack Systems
Air Admittance Valves (AAVs)
Off-Grid Drainage: Cesspools & Septic Tanks
Off-Grid Drainage: Reed Beds
Branch Pipework Design Rules
Macerators: Installation & Operation
Waste Water Lifting Stations
AAV Spacing & Fire Stop Requirements
Calculating Discharge Stack Sizes
Designing Rainwater Systems
Calculating Gutter Sizes
Air Testing Sanitation Systems
Maintaining Macerators & Lifters
Diagnosing Sanitation & Rainwater Faults
Lesson Overview
Air Admittance Valves (AAVs) provide localized ventilation to sanitary pipework under negative pressure, protecting trap water seals without requiring roof penetrations.
Learning Objectives
Understand the internal operating principles and British Standards governing AAVs.
Identify the correct installation heights, locations, and airflow requirements for AAVs.
Recognise the limitations and prohibitions regarding AAV usage on domestic drainage systems.
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