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Upgrade nowPipe Sizing: BS EN 806 & Thomas Box Formula
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
This lesson covers pipe sizing using the BS EN 806-3 simplified method and hydraulic calculations using Thomas Box's formula. You will learn to size distribution pipework, transpose formulas, and select appropriate commercial pipe diameters.
Learning Objectives
Explain the application and limitations of the BS EN 806-3 simplified pipe sizing method.
Calculate pipe diameters and flow rates using Thomas Box's empirical formula.
Transpose Thomas Box's formula and apply commercial sizing rules to maintain residual head.
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