Distribution System Requirements for Fire Protection AWWA MANUAL M31 Fourth Edition
MANUAL OF WATER SUPPLY PRACTICES M31, Fourth Edition Distribution System Requirements for Fire Protection Copyright 1989, 1992, 1998, 2008 American Water Works Association All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information or retrieval system, except in the form of brief excerpts or quotations for review purposes, without the written permission of the publisher. Disclaimer The authors, contributors, editors, and publisher do not assume responsibility for the validity of the content or any consequences of their use. In no event will AWWA be liable for direct, indirect, special, incidental, or consequential damages arising out of the use of information presented in this book. In particular, AWWA will not be responsible for any costs, including, but not limited to, those incurred as a result of lost revenue. In no event shall AWWA s liability exceed the amount paid for the purchase of this book. Project Manager/Technical Editor: Martha Ripley Gray, Melissa Valentine Production Editor: Darice Zimmermann, D&D Editorial Services Manuals Coordinator: Beth Behner Library of Congress Cataloging-in-Publication Data Distribution system requirements for fire protection. -- 4th edition. p. cm. -- (AWWA manual ; M31) Includes bibliographical references and index. ISBN 1-58321-580-8 1. Fire extinction--water-supply. 2. Water--Distribution. I. American Water Works Association. TH9311.D565 2008 628.9 252--dc22 2008006142 Printed in the United States of America American Water Works Association 6666 West Quincy Ave. Denver, CO 80235 Printed on recycled paper
Contents List of Figures, v List of Tables, vii Preface, ix Acknowledgments, xi Chapter 1 Fire Flow Requirements... 1 Impact on Distribution System Design, 1 Community Governance, 2 Fire Flow Requirements, 2 Calculating Fire Flow Requirements, 2 Practical Limits on Fire Flow, 13 Nonpotable Water Sources for Fire Fighting, 15 References, 16 Chapter 2 System Demand and Design Flow Criteria................. 17 Methods of Distribution, 17 Rates of Water Use, 18 Distribution System Appurtenances, 19 System Evaluation and Design, 21 Determining Design Flow, 21 Flow Metering, 22 Standby Charges for Fire Protection Systems, 22 Water Distribution Analysis Techniques, 22 References, 23 Chapter 3 Distribution System Storage.... 25 Functions of Distribution Storage, 25 Elevated and Ground Storage, 27 Pumping for Distribution Storage, 28 Location of Storage, 28 Storage Reservoir Overflow Level, 28 References, 30 Chapter 4 Adequacy and Reliability of Distribution Systems... 31 Determining Level of Reliability, 31 Application of Reliability Considerations, 33 Reliability of Major System Components, 34 Operations, 36 References, 37 iii
Chapter 5 Automatic Fire Sprinkler Systems......................... 39 Advantages of Sprinkler Systems, 39 Water Supply Requirements for Sprinklered Properties, 40 Types of Sprinklers for Commercial Buildings, 42 Standpipes, 43 Backflow Prevention for Fire Sprinkler Systems, 43 References, 45 Appendix A Agencies Involved in Fire Protection..................... 47 Insurance Services Office Inc., 47 Insurance Organizations With Fire Protection Interests, 48 National Fire Protection Association, 48 National Fire Service Associations, 48 Fire Research Laboratories, 48 National Fire Sprinkler Association, 48 American Fire Sprinkler Association, 49 International Code Council, 49 Insurance Bureau of Canada, 49 Insurers Advisory Organization, 49 National Research Council, 49 Underwriters Laboratories of Canada, 49 Appendix B Water Supply and Fire Insurance Ratings... 51 Insurance Ratings, 51 References, 54 Index.............................................................. 55 List of AWWA Manuals... 59 iv
Figures 1-1 Typical occupancy classifications nonmanufacturing, 6 1-2 Typical occupancy classifications manufacturing, 7 1-3 Comparison of fire flow calculations, 12 1-4 Comparison of fire flow calculations, including three exposure buildings, 14 2-1 Typical small city distribution system, 19 3-1 System A hydraulic gradient with no storage, 29 3-2 System B hydraulic gradients with storage between pump station and load center, 29 3-3 System C hydraulic gradients with storage beyond load center, 30 5-1 Sprinkler system design curves, 41 B-1 Water supply evaluation, 53 v
Tables 1-1 Fire flow durations, 3 1-2 Values of coefficient (F) construction class, 4 1-3 Occupancy factors for selected combustibility classes, 5 1-4 Factor for exposure (X i ), 8 1-5 Factor for communications (P i ), 9 1-6 Needed fire flow for one- and two-family dwellings, 9 2-1 Values commonly used in distribution piping, 20 3-1 Water use and storage depletion for maximum day in a typical city, 26 5-1 Hazard classification schedule, 42 vii
Index No t e: f. indicates a figure; t. indicates a table. AFSA (American Fire Sprinkler Association), 49 Agencies, fire protection, 47 49 A i (effective area), 4 5 Alarms, fire, 37 American Fire Sprinkler Association (AFSA), 49 Analysis techniques, water distribution, 22 Area method, 20 Arterial mains, 19 Automatic fire sprinkler systems, 39 45 advantages of, 39 40 backflow prevention, 43 44 for commercial buildings, 42 43 overview, 39 standpipes, 43 water supply requirements for, 40 42 Average daily demand, 18 AWWA manuals, 59 60 Backflow prevention, 43 44 Backup pumps, 35 Blowoff valves, 19 20 Breaks, pipe, 34 Buildings automatic fire sprinkler systems for, 42 43 exposure factor, 8t. nonsprinklered, 13 14 reliability of, 35 36 sprinklered, 15 Capability of water systems, 53 Capacity, pumping, 34 35 Charges, standby, 22 C i (construction factor), 4 City distribution systems, 19f. Cleanings, pipe, 34 Coefficient (F) construction class values, 4t. Combustibility classes, 5t. Communication (P i ) factors, 5 7, 9t. Community governance, 2, 14 15 Construction, classes of, 4t. Construction factor (C i ), 4 Construction scenarios, 11 13 Costs of distribution systems, 31, 33 of fire protection improvements, 54 of sizing distribution systems, 1 2 of sprinkler systems, 39 40 Daily demand, 18, 21 22 Demand rates of water use, 18 19, 25 27 Density, 40 Design of distribution systems, 1, 21, 33 34 of sprinkler systems, 44 Design curves, sprinkler system, 40 41, 41f. Design flow criteria, 17 23 demand rates of water use, 18 19 determining design flow, 21 22 distribution system appurtenances, 19 21 evaluation and design, 21 flow metering, 22 methods of distribution, 17 18 overview, 17 standby charges for fire protection systems, 22 water distribution analysis techniques, 22 Direct pumping systems, 28 Distribution piping values, 20t. Distribution systems. See also Design flow criteria appurtenances, 19 21 design of, 1, 21, 33 34 evaluations of, 21 looping, 19 methods of distribution, 17 18 ratings of, 56 57 reliability, 31 37 application of considerations, 33 34 determining level of, 31 33 major system components, 34 36 operations, 36 37 overview, 31 sizing of, 1 2 storage, 25 30 depletion of, 26t. elevated and ground storage, 27 functions of, 25 27 location of, 28 overview, 25 pumping for, 28 reliability of reservoirs, 34 reservoir overflow levels, 28 30 testing of, 52 for typical cities, 19f. water distribution analysis techniques, 22 Divergence, 53 54 Dual distribution systems, 15 Durations, flow, 3, 3t. Effective area (A i ), 4 5 Elevated water storage, 17 18, 27 28 Emergency services, 37 Evaluations, distribution system, 21 Exposure (X i ) factor, 5 7, 8t. 55
56 Fire Protection Exposure buildings, 11, 14f., 35 F (coefficient) construction class values, 4t. Factory FM Global laboratory, 48 Feeders, 19 Fire alarms, 37 Fire departments, 36 Fire flow requirements, 1 16 calculating, 2 13 comparison of methods, 11 13, 12f., 14f. flow durations, 3 Illinois Institute of Technology Research Institute method, 11 Insurance Services Office method, 3 7, 9t. Iowa State University method, 7 10 National Fire Academy method, 10 overview, 2 3 community governance of, 2 distribution storage and, 25 27 distribution system reliability and, 32 impact on distribution system design, 1 nonpotable water sources, 15 overview, 1 practical limits on, 13 15 understanding water use, 2 Fire hydrant flow tests, 21 22, 34, 56 57. See also Hydrants Fire protection agencies, 51 53 Fire protection plans, 2 Fire research laboratories, 52 Fire sprinkler systems. See Automatic fire sprinkler systems Fire Suppression Rating Schedule publication, 3, 9t., 51 52 Fire suppression systems, 13, 47 49 Fire Underwriters Survey (FUS), 49 Floor areas, 4 Flow durations, 3, 3t. Flow metering, 22 Flow tests, fire hydrant, 21 22, 34, 52 53 Fresno, California, 39 40 Fuel supply, pumping, 35 FUS (Fire Underwriters Survey), 49 Generators, 18 Governance, community, 2, 14 15 Grading schedules, 51 Gravity distribution, 17 Ground storage, 27 Guarantees of pressure, 44 Hazard classification schedule, 42t. Hazard classifications, sprinkler systems, 41 42 Hose streams, 40, 43 Hourly demand, 18, 21 22 Hydrants distribution of, 52 locations of, 20 21 private, 43 testing and maintenance of, 36 Hydraulically calculated systems, 42 43 Hydraulic gradient systems, 29 30f. Hydraulic models of distribution systems, 22 Hydropneumatic tanks, 28 IAO (Insurers Advisory Organization), 49 Illinois Institute of Technology Research Institute (IITRI) method, 11, 12f. Indirect pumping systems, 28 Individual fire protection systems, 34 Insurance Bureau of Canada, 49 Insurance organizations, 48 Insurance ratings, 51 54 Insurance Services Office Inc. (ISO), 3 7, 12f., 47 48, 54 Insurers Advisory Organization (IAO), 49 Interconnected utilities, 27 International Code Council, 49 Iowa State University (ISU) method, 7 10, 12f. ISO (Insurance Services Office Inc.), 3 7, 12f., 47 48, 54 Laboratories, fire research, 48 Laterals, 20 Limits, fire flow, 13 15 Linear method, 20 Local components, 33 Local distribution lines, 32 Looping distribution systems, 19, 32 Main capacity, 52 Maintenance of hydrants, 36 Major system components, 33 Major transmission facilities, 32 Manuals, AWWA, 59 60 Manufacturing occupancy classifications, 7 Maximum daily demand, 18, 21 22 Maximum hourly demand, 18, 21 22 Metering flows, 22 Models, distribution design, 22 National Fire Academy (NFA) method, 10, 12f. National Fire Protection Association (NFPA), 48 National Fire Service Association, 48 National Fire Sprinkler Association (NFSA), 48 49 National Research Council, 49 Needed fire flow (NFF) Illinois Institute of Technology Research Institute method, 11 Insurance Services Office method, 3 Iowa State University method, 7, 10 National Fire Academy method, 10 for one- and two-family buildings, 9t. NFA (National Fire Academy) method, 10, 12f. NFPA (National Fire Protection Association), 48 NFSA (National Fire Sprinkler Association), 48 49 Nonmanufacturing occupancy classifications, 6 Nonpotable water sources, 15
Index 57 Nonsprinklered buildings, 13 14 Occupancy classifications, 6 7f. Occupancy factors (O i ), 5, 5t. Operation of distribution systems, 33 34, 36 37 Out of service components, 32 Overflow elevation, 28 30 Overhead power lines, 35 P i (communication) factors, 5 7, 9t. Pipe schedule systems, 42 Piping systems breaks in, 34 cleanings of, 33 common values in, 20t. components of, 19 20 reliability of, 36 Plans, fire protection, 2 Power lines, 35 Power supply, pumping, 35 Primary feeders, 19 Private hydrants, 43 Public protection systems, 55 58 Pumping systems direct, 28 indirect, 28 reliability of, 34 35 for storage distribution, 27 Pumps, 17 18, 27 Rates of water use, 18 Ratings, insurance, 51 54 Records, maintenance, 36 Reliability of distribution systems, 31 37 application of considerations, 33 34 determining level of, 31 33 major system components, 34 36 operations, 36 37 overview, 31 Required fire flow, 1 16 calculating, 2 13 comparison of methods, 11 13 flow durations, 3 Illinois Institute of Technology Research Institute method, 11 Insurance Services Office method, 3 7 Iowa State University method, 7 10 National Fire Academy method, 10 overview, 2 3 community governance of, 2 distribution storage and, 25 27 distribution system reliability and, 32 impact on distribution system design, 1 nonpotable water sources, 15 overview, 1 practical limits on, 13 15 understanding water use, 2 Reservoirs overflow levels for, 28 30 pumping from, 17 18 Secondary feeders, 19 Sizing distribution systems, 1 2, 22 of pipes, 19 20 Sprinklered buildings, 15 Sprinkler system design curves, 41f. Sprinkler systems. See Automatic fire sprinkler systems Standby charges, 22 Standpipes, 43 Storage, distribution system, 25 30 depletion of, 26t. elevated and ground storage, 27 functions of, 25 27 location of, 28 overview, 25 pumping for, 28 reliability of reservoirs, 34 reservoir overflow levels, 28 30 Suction supplies, 15 Supply works capacity, 56 Tanks fuel, 35 ground, 27 hydropneumatic, 28 location of, 28 Testing distribution systems, 52 of hydrants, 21 22, 34, 36, 52 53 ULC (Underwriters Laboratories of Canada), 53 Underground power lines, 35 Underwriters Laboratories, 48 United States Fire Administration, 10 Underwriters Laboratories of Canada (ULC), 53 Upgrading systems, 33 Utilities, interconnected, 27 Valves, 19 20, 33 Water adequacy of supply, 51 54 daily use and storage depletion of, 26t. demand rates, 18 19 nonpotable sources of, 15 supply evaluation, 53f. supply requirements for sprinkler systems, 40 42 use of, 2 Water pressure in gravity distribution, 17 for sprinkler design, 44 Water systems, 52. See also Distribution systems; Fire flow requirements Water treatment plants, 35 36 Water utilities, 36 X i (exposure) factor, 5 7, 8t.
AWWA Manuals M1, Principles of Water Rates, Fees, and Charges, Fifth Edition, 2000, #30001PA M2, Instrumentation and Control, Third Edition, 2001, #30002PA M3, Safety Practices for Water Utilities, Sixth Edition, 2002, #30003PA M4, Water Fluoridation Principles and Practices, Fifth Edition, 2004, #30004PA M5, Water Utility Management Practices, Second Edition, 2006, #30005PA M6, Water Meters Selection, Installation, Testing, and Maintenance, Second Edition, 1999, #30006PA M7, Problem Organisms in Water: Identification and Treatment, Third Edition, 2004, #30007PA M9, Concrete Pressure Pipe, Second Edition, 1995, #30009PA M11, Steel Pipe A Guide for Design and Installation, Fifth Edition, 2004, #30011PA M12, Simplified Procedures for Water Examination, Fifth Edition, 2002, #30012PA M14, Recommended Practice for Backflow Prevention and Cross-Connection Control, Third Edition, 2003, #30014PA M17, Installation, Field Testing, and Maintenance of Fire Hydrants, Fourth Edition, 2006, #30017PA M19, Emergency Planning for Water Utility Management, Fourth Edition, 2001, #30019PA M20, Water Chlorination/Chloramination Practices and Principles, Second Edition, 2006, #30020PA M21, Groundwater, Third Edition, 2003, #30021PA M22, Sizing Water Service Lines and Meters, Second Edition, 2004, #30022PA M23, PVC Pipe Design and Installation, Second Edition, 2003, #30023PA M25, Flexible-Membrane Covers and Linings for Potable-Water Reservoirs, Third Edition, 2000, #30025PA M27, External Corrosion Introduction to Chemistry and Control, Second Edition, 2004, #30027PA M28, Rehabilitation of Water Mains, Second Edition, 2001, #30028PA M29, Fundamentals of Water Utility Capital Financing, Third Edition, 2008, #30029PA M30, Precoat Filtration, Second Edition, 1995, #30030PA M31, Distribution System Requirements for Fire Protection, Third Edition, 1998, #30031PA M32, Distribution Network Analysis for Water Utilities, Second Edition, 2005, #30032PA M33, Flowmeters in Water Supply, Second Edition, 2006, #30033PA M36, Water Audits and Leak Detection, Second Edition, 1999, #30036PA M37, Operational Control of Coagulation and Filtration Processes, Second Edition, 2000, #30037PA M38, Electrodialysis and Electrodialysis Reversal, First Edition, 1995, #30038PA M41, Ductile-Iron Pipe and Fittings, Second Edition, 2003, #30041PA M42, Steel Water-Storage Tanks, First Edition, 1998, #30042PA M44, Distribution Valves: Selection, Installation, Field Testing, and Maintenance, Second Edition, 2006, #30044PA M45, Fiberglass Pipe Design, Second Edition, 2005, #30045PA M46, Reverse Osmosis and Nanofiltration, Second Edition, 2007, #30046PA M47, Construction Contract Administration, First Edition, 1996, #30047PA M48, Waterborne Pathogens, Second Edition, 2006, #30048PA M49, Butterfly Valves: Torque, Head Loss, and Cavitation Analysis, First Edition, 2001, #30049PA M50, Water Resources Planning, Second Edition, 2007, #30050PA To order any of these manuals or other AWWA publications, cal lthe Bookstore toll-free at 1.800.926.7337. 59
60 Fire Protection M51, Air-Release, Air/Vacuum, and Combination Air Valves, First Edition, 2001, #30051PA M52, Water Conservation Programs A Planning Manual, First Edition, 2006, #30052PA M53, Microfiltration and Ultrafiltration Membranes for Drinking Water, First Edition, 2005, #30053PA M54, Developing Rates for Small Systems, First Edition, 2004, #30054PA M55, PE Pipe Design and Installation, First Edition, 2006, #30055PA M56, Fundamentals and Control of Nitrification in Chloraminated Drinking Water Distribution Systems, First Edition, 2006, #30056PA To order any of these manuals or other AWWA publications, cal lthe Bookstore toll-free at 1.800.926.7337.