Backflow Prevention: Theory and Practice

CHAPTER ONE: INTRODUCTION TO BACKFLOW PREVENTION
Introduction
Backflow/Cross-Connections
Non-potable Source/Contaminant/Pollutant
Backpressure/Backsiphonage
Public Health Significance
Backflow Prevention
Purpose and Scope
Summary
Chapter One Review

CHAPTER TWO: THE HAZARDS OF BACKFLOW
Biological Pollution/Contamination
Backflows Short-circuit the Water Treatment Process
Public Health Significance
Monetary Costs of Biological Contamination
Biological Hazards: Case Histories
Factors That Affect the Magnitude of a Biological Backflow Incident
Chemical Pollution/Contamination
Public Health Significance
Monetary Cost of Chemical Contaminants
Chemical Hazards: Case Histories
Factors That Affect the Magnitude of a Chemical Backflow Incident
Summary
Chapter Two Review

CHAPTER THREE: LAWS AND RESPONSIBILITY
Laws
Federal Regulations
State Regulations
Regulations in Other States
Plumbing Codes
Responsibilities and Liabilities
Liabilities and Damages
Individual Responsibilities
Water Purveyors
Consumer
Regulatory Officials
Plumbing Inspector
Consulting Engineers
Contractors, Plumbers, and Testers
Code of Conduct
Others with Some Level of Responsibility
Summary
Chapter Three Review

CHAPTER FOUR: FUNDAMENTALS OF BACKFLOW
Cross-Connections
Types of Cross-Connections
Why Cross-Connections Are Created
Understanding Backflow
Pressure Principles
Water: Under Static Conditions
Atmospheric Pressure
Water Movement
Effects of the Weight of Water
Effects of Atmospheric Pressure
Effects of Water Temperature
Effects of Water Velocity
Mechanical Devices
Backpressure
Backsiphonage
Summary
Chapter Four Review

CHAPTER FIVE: METHODS AND MECHANISMS FOR PREVENTING BACKFLOW
Devices and Approved Assemblies
Mechanical Backflow Preventers
Atmospheric Vacuum Breaker
Hose Bibb Vacuum Breaker
Pressure Vacuum Breaker
Backflow Protection for Irrigation Systems
Spill-resistant Vacuum Breaker Assembly
Double Check Valve Assembly
Reduced Pressure Principle Assembly
Air Gap: Approved Non-mechanical Backflow Prevention
Summary of Approved Backflow Prevention Methods
Other Backflow Preventers
Barometric Loop
Single Check Valve
Dual Check Valve
Auxiliary Methods for Preventing Backflow
Detector Check
Double Check Detector Assembly
Reduced Pressure Detector Assembly
Commercial Fire Sprinkler Systems
Wet Pipe Fire Sprinkler System
Deluge Sprinkler System
Combined Dry Pipe-Preaction Sprinkler System
Dry Pipe Sprinkler System
Preaction Sprinkler System
Residential Fire Sprinkler System (Single Family)
Assembly Installation
Thermal Expansion
Temperature and Pressure Valve
Freeze Protection
Summary
Chapter Five Review

CHAPTER SIX: FIELD TESTING
Test Gauges
Differential Pressure Gauge
Sight Tube
Testing
Testing the Reduced Pressure Principle Assembly
Step-by-step Testing Procedure for the Reduced Pressure Principle Assembly
Testing the Reduced Pressure Principle Assembly with a Leaking
Outlet Shut-off Valve
Testing the Reduced Pressure Detector Assembly
Testing the Double Check Valve Assembly
Step-by-step Testing Procedures for the DCVA, Differential Pressure Gauge Single-hose Method
Testing the DCVA with a Leaking Inlet Shut-off Valve, Differential Pressure Gauge Method
Testing the DCVA with a Leaking Outlet Shut-off Valve, Differential Pressure Gauge Method
Sight Tube Method
Step-by-step Testing Procedures for the DCVA, Sight Tube Method
Testing the DCVA with a Leaking Inlet Shut-off Valve, Sight Tube Method
Testing the Double Check Detector Assembly
Testing the Pressure Vacuum Breaker
Step-by-step Testing Procedures for the Pressure Vacuum Breaker
Testing the Pressure Vacuum Breaker with a Leaking Inlet Shut-off Valve
Step-by-step Testing Procedures for the Spill-resistant Vacuum Breaker
Testing the Spill-resistant Vacuum Breaker with a Leaking Inlet Shut-off Valve
Testing Follow-up
Summary
Chapter Six Review

CHAPTER SEVEN: TROUBLESHOOTING, MAINTENANCE, AND REPAIR
Troubleshooting Reduced Pressure Principle Assemblies
Testing the Reduced Pressure Principle Assembly with a Leaking Outlet Shut-off Valve
Maintenance and Repair
Safety
Repair
Items to Check When the Backflow Preventer Fails
Reduced Pressure Principle Assembly and Reduced Pressure Detector Assembly
Double Check Valve Assembly and Double Check Detector Assembly
Pressure Vacuum Breaker and Spill-Resistant Vacuum Breaker Assembly
Atmospheric Vacuum Breaker Device
Residential Dual Check Device
General Items to Check When the Backflow Preventer Fails
Corrosion
Water Quality
Summary
Chapter Seven Review

CHAPTER EIGHT: DEVELOPING A CROSS-CONNECTION CONTROL PROGRAM
Getting Started
Administration of the Program
An Ordinance
Service Contracts
Policies and Rules
Standard Operating Procedures
Administrative Authority
Seven Elements of a Cross-Connection Control Program
Establishing Legal Authority
Plan Review of New Construction
Using Standards and Specifications to Define “Approved” Assemblies
Testing and Maintenance
Record Keeping
Program for Surveying and Retrofitting Existing Facilities
Training and Education
Developing a Program for Dealing with Emergencies
Program Manual
Summary

SUGGESTED SUPPLEMENTARY READINGS

GLOSSARY

INDEX

APPENDIX
Appendix A AWWA Policy Statement
Appendix B Florida Department of Environmental Protection Rule 62-555.360
Appendix C Abbreviations
Appendix D Field Test Procedures: RP, DCVA, PVB, SVB
Appendix E Test and Maintenance Report Form
Appendix F Troubleshooting Guide
Appendix G Test Kits: Suppliers and Repair Locations
Appendix H Repair Parts Suppliers
Appendix I Florida Building Code – Plumbing
Appendix J FCCC & HR Approval Process
Appendix K Testing the RP Chart
Appendix L A.S.S.E. Numbers: Approved Assemblies and Devices
Appendix M Building a Model Backflow Prevention Program
Appendix N Elements of Program Ordinance
Appendix O Form Letters: Required Annual Testing, Follow-up, Final, and Repair
Appendix P List of High Hazard Facilities
Appendix Q CCC Questionnaire
Appendix R Survey Inspection Forms
Appendix S Sample Inspection Letters: Initial Letter Follow-up Letter
Appendix T List of Common Cross-Connection Locations
Appendix U Incident Report Form
Appendix V Selecting the Proper Backflow Prevention Assembly
Appendix W Nomenclature Chart: Valves, Shut-Off, Check, Needle and Test Cocks
Appendix X Lawn Irrigation Systems
Appendix Y Article on Reclaimed Water (Re-use)
Appendix Z Enclosures for Freeze Protection