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NFPA 16
Standard for the
Installation of Foam Water Sprinkler and Foam Water Spray
Systems
2007 Edition
Copyright © 2007 National Fire Protection Association. All Rights Reserved.
This edition of NFPA 16, Standard for the Installation of FoamW ater Sprinkler and FoamW ater Spray Systems, was prepared by the Technical Committee on Foam Water Sprinklers and released by the Technical Correlating Committee on Automatic Sprinkler Systems. It was issued by the Standards Council on December 1, 2006, with an effective date of December 20, 2006, and supersedes all previous editions.
This edition of NFPA 16 was approved as an American National Standard on December 20,
Origin and Development of NFPA 16
The first standard involving foam water sprinkler systems was published in 1954 by the National Board of Fire Underwriters (now American Insurance Association) and was titled Standard for Combined Foam and Water Spray Systems. The NFPA Technical Committee on Foam Water Sprinklers was established in 1959 with assistance from the NBFU. The first edition of this standard was published in 1962.
Various updates to the standard were completed in 1968, 1974, 1988, and 1990. Changes were made to recognize the use of new foam concentrates and to improve the language and format of the document.
The 1995 edition included clarification of the scope of the standard, improvements to the hydraulic design criteria, and recognition of a fourth proportioning method.
The 1999 edition combined NFPA 16 and NFPA 16A into one comprehensive document. Numerous editorial changes also were instituted.
The 2003 edition was reformatted to conform to the Manual of Style for NFPA Technical Committee Documents and was revised to recognize the use of different types and brands of foam concentrate.
The 2007 edition of the standard has been revised to coordinate definitions and requirements for fire department connections and underground pipe with those of other documents.
Technical Correlating Committee on Automatic Sprinkler Systems (AUT AAC)
John G. O’Neill, Chair The Protection Engineering Group, PC, VA [SE]
Christian Dubay, Nonvoting Secretary National Fire Protection Association, MA
José R. Baz, JRB Associates Group Incorporated, FL [M] Rep. NFPA Latin American Section
Kerry M. Bell, Underwriters Laboratories Incorporated, IL [RT]
Russell P. Fleming, National Fire Sprinkler Association, NY [M]
Scott T. Franson, The Viking Corporation, MI [M]
Michael J. Friedman, Friedman Consulting, Incorporated, MD [SE]
Raymond A. Grill, Arup Fire, DC [SE]
James B. Harmes, Grand Blanc Fire Department, MI [E] Rep. International Association of Fire Chiefs
Luke Hilton, Liberty Mutual Property, NC [I]
Alex Hoffman, Viking Fire Protection Incorporated, Canada [IM] Rep. Canadian Automatic Sprinkler Association
Roland J. Huggins, American Fire Sprinkler Association, Incorporated, TX [IM]
Sultan M. Javeri, SC Engineering, France [IM]
Andrew Kim, National Research Council of Canada, Canada [RT]
Joe W. Noble, Clark County Fire Department, NV [E] Rep. International Fire Marshals Association
Eric Packard, Local 669 JATC Education Fund, MD [L] Rep. United Association of Journeymen and Apprentices of the Plumbing & Pipe Fitting Industry of the United States & Canada
Chester W. Schirmer, Schirmer Engineering Corporation, NC [I]
Rep. TC on Sprinkler System Installation Criteria
Daniel Madrzykowski, U.S. National Institute of Standards & Technology, MD [RT] Rep. TC on Residential Sprinkler Systems
Bill Sheppard, General Motors Corporation, MI [U] Rep. TC on Private Water Supply Piping Systems
John J. Walsh, UA Joint Apprenticeship Committee, MD [SE] (Member Emeritus)
Christian Dubay, NFPA Staff Liaison
This list represents the membership at the time the Committee was balloted on the final text of this edition. Since that time, changes in the membership may have occurred. A key to classifications is found at the back of the document. NOTE: Membership on a committee shall not in and of itself constitute an endorsement of the Association or any document developed by the committee on which the member serves. Committee Scope: This Committee shall have overall responsibility for documents that pertain to the criteria for the design and installation of automatic, open and foamw ater sprinkler systems including the character and adequacy of water supplies, and the selection of sprinklers, piping, valves, and all materials and accessories. This Committee does not cover the installation of tanks and towers, nor the installation, maintenance, and use of central station, proprietary, auxiliary, and local signaling systems for watchmen, fire alarm, supervisory service, or the design of fire department hose connections.
Technical Committee on Foam Water Sprinklers (AUT FOW)
Robert M. Gagnon, Chair Gagnon Engineering, MD [SE]
Terry L. Victor, Secretary Tyco/SimplexGrinnell, MD [M]
Michael E. Aaron, The RJA Group, Incorporated, IL [SE]
Tracey D. Bellamy, TVA Fire and Life Safety, Incorporated, GA [SE]
William F. Blackmon, Pirelli North America, TN [U]
Pascal Caron, Montreal Fire Department, Canada [E]
Bruce G. Carpenter, AERO Automatic Sprinkler Company, AZ [IM ]
Kevin F. Carrier, Miami Dade County, FL [E]
David L. Dixon, Security Fire Protection, TN [IM]
Rep. National Fire Sprinkler Association
Larry J. Edwards, F. E. Moran, Incorporated, IL [IM]
Richard Greenberg, New Jersey Department of Community Affairs, NJ [E]
Robert Lee Holcombe, III, GE Insurance Solutions, SC [I]
Alan L. Holder, Louisiana Power & Light Company, LA [U] Rep. Edison Electric Institute
Gene L. Hortz, Rohm and Haas Company, PA [U]
Kirk W. Humbrecht, Phoenix Fire Systems, Incorporated, IL [IM] Rep. Fire Suppression Systems Association
Eldon D. Jackson, The Viking Corporation, MI [M] Rep. National Fire Sprinkler Association
Kevin P. Kuntz, Marsh USA Incorporated, NJ [I]
Scott L. Maxwell, Fireman's Fund Insurance Company, CO [I]
Robert C. Merritt, FM Global, MA [I]
Bob D. Morgan, Fort Worth Fire Department, TX [E]
Randy R. Nelson, PE, VFS Fire & Security Services, CA [IM] Rep. American Fire Sprinkler Association
Thomas A. Noble, City of Henderson Building & Fire Safety, NV [E]
Maurice M. Pilette, Mechanical Designs Limited, MA [SE]
Tommy L. Preuett, Ellicott City, MD [L] Rep. United Association of Journeymen & Apprentices of the Plumbing & Pipe Fitting Industry of the United States & Canada
Paul E. Rivers, 3M Fire Protection, MN [M]
Joseph L. Scheffey, Hughes Associates, Incorporated, MD [SE]
Thomas M. Suehr, Liberty Mutual Property, MA [I] Rep. Property Casualty Insurers Association of America
Jeffery W. Sutton, Global Risk Consultants Corporation, MN [SE ]
Standard for the Installation of Foam Water Sprinkler and Foam Water Spray Systems 2007 Edition
IMPORTANT NOTE: This NFPA document is made available for use subject to important notices and legal disclaimers. These notices and disclaimers appear in all publications containing this document and may be found under the heading “Important Notices and Disclaimers Concerning NFPA Documents.” They can also be obtained on request from NFPA or viewed at www.nfpa.org/disclaimers.
NOTICE: An asterisk (*) following the number or letter designating a paragraph indicates that explanatory material on the paragraph can be found in Annex A.
Changes other than editorial are indicated by a vertical rule beside the paragraph, table, or figure in which the change occurred. These rules are included as an aid to the user in identifying changes from the previous edition. Where one or more complete paragraphs have been deleted, the deletion is indicated by a bullet (•) between the paragraphs that remain.
A reference in brackets [ ] following a section or paragraph indicates material that has been extracted from another NFPA document. As an aid to the user, the complete title and edition of the source documents for extracts in mandatory sections of the document are given in Chapter 2 and those for extracts in informational sections are given in Annex C. Editorial changes to extracted material consist of revising references to an appropriate division in this document or the inclusion of the document number with the division number when the reference is to the original document. Requests for interpretations or revisions of extracted text shall be sent to the technical committee responsible for the source document.
Information on referenced publications can be found in Chapter 2 and Annex C.
Chapter 1 Administration
1.1 Scope.
1.1.1 This standard contains minimum requirements for the design, installation, and maintenance of foam water sprinkler and spray systems. These systems shall be designed with the required density for either foam or water application as the controlling factor, depending on the design purpose of the system. It is not the intent of this standard to specify where foam water sprinkler and spray protection is required. The determination of where foam water sprinkler and spray systems are required shall be made in accordance with such applicable standards as NFPA 30, Flammable and Combustible Liquids Code , and NFPA 409, Standard on Aircraft Hangars.
1.1.2* This standard shall apply only to systems using lowex pansion foam.
1.2 Purpose.*
The purpose of this standard is to provide a reasonable degree of protection for life and property from fire through installation requirements for foam water sprinkler and spray
systems based on sound engineering principles, test data, and field experience.
1.3 Application.
1.3.1* Because of the dual extinguishing agent discharge characteristic, these systems shall be selectively applicable to combination Class A and Class B hazards.
1.3.2 Foam water deluge systems are applicable to the protection of two dimensional flammable liquid hazards. They shall be permitted to be used for any of the purposes or combinations thereof detailed in 1.3.2.1 through 1.3.2.3.
1.3.2.1 Extinguishment. The primary purpose of such systems is the extinguishment of fire in the protected hazard. For this purpose, foam solution discharge densities shall be provided by system design, use of selected discharge devices, and provision of supplies of water at required pressures to accomplish the system design. Foam discharge rates shall be able to provide required rates of water discharge from the system until shut off during the design period and following depletion of foam concentrate supplies.
1.3.2.2 Prevention. Prevention of fire in the protected hazard is a supplemental feature of such systems. Manual operation of a system to discharge foam or water selectively from the discharge devices in case of accumulations of hazardous materials from spills in such occupancies as garages, aircraft hangars, petrochemical plants, paint and varnish plants, or from other causes in the protected area, will afford protection against ignition, pending cleanup measures. In such cases, manual system operation provides foam coverage in the area with water discharge manually available.
1.3.2.3 Control and Exposure Protection. Control of fire to allow controlled burning of combustible materials where extinguishment is not possible and exposure protection to reduce heat transfer from an exposure fire can be accomplished by water spray or foam, or both, from these special systems. The degree of accomplishment is related strongly to the fixed discharge densities provided by the system design.
1.3.3 Foam of any type is not an effective extinguishing agent on fires involving liquefied or compressed gases (e.g., butane, butadiene, propane), on materials that will react violently with water (e.g., metallic sodium) or that produce hazardous materials by reacting with water, or on fires involving electrical equipment where the electrical nonconductivity of the extinguishing agent is of primary importance.
1.3.4* Only alcohol type foam shall be used on fires in water soluble solvents and polar solvents. Manufacturers of foam concentrates that are manufactured for the protection of such hazards shall be consulted for applicability.
1.3.5* Consideration shall be given to potential contamination of water supplies, treating systems, and effluent by foam concentrate, foam, or foam solution runoff. The foam concentrate manufacturer and the appropriate authority having jurisdiction shall be consulted for guidance.
1.4 Retroactivity.
The provisions of this standard reflect a consensus of what is necessary to provide an
1.6.1 If a value for measurement as given in this standard is followed by an equivalent value in other units, the first stated shall be regarded as the requirement. A given equivalent value shall be considered to be approximate.
1.6.2 SI units have been converted by multiplying the quantity by the conversion factor and then rounding the result to the appropriate number of significant digits.
Chapter 2 Referenced Publications
2.1 General.
The documents or portions thereof listed in this chapter are referenced within this standard and shall be considered part of the requirements of this document.
2.2 NFPA Publications.
National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169 7471.
NFPA 11, Standard for Low , Medium, and High Expansion Foam, 2005 edition.
NFPA 13, Standard for the Installation of Sprinkler Systems, 2007 edition.
NFPA 14, Standard for the Installation of Standpipe and Hose Systems, 2007 edition.
NFPA 15, Standard for Water Spray Fixed Systems for Fire Protection, 2007 edition.
NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, 2007 edition.
NFPA 22, Standard for Water Tanks for Private Fire Protection, 2003 edition.
NFPA 24, Standard for the Installation of Private Fire Service Mains and Their Appurtenances, 2007 edition.
NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water Based Fire Protection Systems, 2002 edition.
NFPA 30, Flammable and Combustible Liquids Code, 2003 edition.
NFPA 70, National Electrical Code®, 2005 edition.
NFPA 72 ®, National Fire Alarm Code®, 2007 edition.
NFPA 409, Standard on Aircraft Hangars, 2004 edition.
NFPA 1963, Standard for Fire Hose Connections, 2003 edition.
2.3 Other Publications.
2.3.1 ASME Publications.
American Society of Mechanical Engineers, Three Park Avenue, New York, NY
ASME Boiler and Pressure Vessel Code , Section VIII, Division 1, Rules for Construction of Pressure Vessels, 1998.
2.3.2 ASTM Publications.
ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428 2959.
ASTM SI 10, Standard for Use of the International System of Units (SI): The Modern Metric System , 1997 edition.
2.3.3 Other Publications.
Merriam Webster’s Collegiate Dictionary, 11th edition, Merriam Webster, Inc., Springfield, MA, 2003.
2.4 References for Extracts in Mandatory Sections.
NFPA 11, Standard for Low , Medium, and High Expansion Foam, 2005 edition.
NFPA 13, Standard for the Installation of Sprinkler Systems, 2007 edition.
Chapter 3 Definitions
3.1 General.
The definitions contained in this chapter shall apply to the terms used in this standard. Where terms are not defined in this chapter or within another chapter, they shall be defined using their ordinarily accepted meanings within the context in which they are used. Merriam Webster’s Collegiate Dictionary , 11th edition, shall be the source for the ordinarily accepted meaning.
3.2 NFPA Official Definitions.
3.2.1 Approved.* Acceptable to the authority having jurisdiction.
3.2.2 Authority Having Jurisdiction (AHJ).* An organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.
3.2.3 Listed.* Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets appropriate designated standards or has been tested and found suitable for a specified purpose.
3.2.4 Shall. Indicates a mandatory requirement.
3.2.5 Should. Indicates a recommendation or that which is advised but not required.
opened sprinklers.
3.3.5.3 Foam Water Preaction System.* A sprinkler system employing automatic sprinklers or nozzles attached to a piping system containing air that might or might not be under pressure, with a supplemental detection system installed in the same area as the sprinklers. Actuation of the detection system opens a valve that permits water to flow into the sprinkler piping system and to be discharged from any sprinklers that have activated.
3.3.5.4 Foam Water Spray System.* A special system that is pipeco nnected to a source of foam concentrate and to a water supply. The system is equipped with foam water spray nozzles for extinguishing agent discharge (foam followed by water or in reverse order) and for distribution over the area to be protected. System operation arrangements parallel those for foam water sprinkler systems as described in the definition of Foam Water Sprinkler System.
3.3.5.5 Preprimed System.* A wet pipe system containing foam solution.
3.3.6 Foam Concentrate.* A concentrated liquid foaming agent as received from the manufacturer. [ 11, 2005]
3.3.6.1 Alcohol Resistant Foam Concentrate.* A concentrate used for fighting fires on water soluble materials and other fuels destructive to regular, AFFF, or FFFP foams, as well as for fires involving hydrocarbons. [ 11, 2005]
3.3.6.2 Aqueous Film Forming Foam Concentrate (AFFF).* A concentrate based on fluorinated surfactants plus foam stabilizers and usually diluted with water to a 1 percent, 3 percent, or 6 percent solution. [ 11, 2005]
3.3.6.3 Film Forming Fluoroprotein Foam Concentrate (FFFP).* A concentrate that uses fluorinated surfactants to produce a fluid aqueous film for suppressing hydrocarbon fuel vapors. [ 11, 2005]
3.3.6.4 Fluoroprotein Foam Concentrate.* A concentrate very similar to protein foam concentrate but with a synthetic fluorinated surfactant additive. [ 11, 2005]
3.3.6.5 Medium and High Expansion Foam Concentrate.* A concentrate, usually derived from hydrocarbon surfactants, used in specially designed equipment to produce foams having foam to solution volume ratios of 20:1 to approximately 1000:1. [ 11, 2005]
3.3.6.6 Other Synthetic Foam Concentrate.* A concentrate based on hydrocarbon surface active agents and listed as a wetting agent, foaming agent, or both. [ 11, 2005]
3.3.6.7 Protein Foam Concentrate.* Concentrate consisting primarily of products from a protein hydrolysate, plus stabilizing additives and inhibitors to protect against freezing, to prevent corrosion of equipment and containers, to resist bacterial decomposition, to control viscosity, and to otherwise ensure readiness for use under emergency conditions. [ 11, 2005]
3.3.6.8 Synthetic Foam Concentrate. Concentrate based on foaming agents other than hydrolyzed proteins and including aqueous film forming foam (AFFF) concentrates, medium and high expansion foam concentrates, and other synthetic foam concentrates. [ 11, 2005]
3.3.7 Foam Solution.* A homogeneous mixture of water and foam concentrate in the
correct proportions. [ 11, 2005]
3.3.8 Proportioning. The continuous introduction of foam concentrate at the recommended ratio into the water stream to form foam solution. [ 11, 2005]
3.3.9 Rate. The total flow of solution per unit of time, which is expressed in gpm (L/min) in this standard.
Chapter 4 General Requirements
4.1 General System Information.
4.1.1 Foam water deluge and preaction systems shall be provided with automatic and auxiliary manual tripping means in accordance with Section 5.12.
4.1.2 Manual operation only shall be permitted for foam water deluge systems where acceptable to the authority having jurisdiction.
4.2 Types of Systems.
Foam water systems shall be of the wet pipe, dry pipe, deluge, or preaction type.
4.3 Foam Discharge Duration.
4.3.1 Systems shall deliver foam to the hazards they protect for a specified period at given densities, either prior to water discharge or following water discharge, depending upon system design purpose.
4.3.2 Following completion of discharge of foam solution to the hazards protected, foam water sprinkler and spray systems shall discharge water until manually shut off.
4.4 Reserve Supply of Foam.*
4.4.1 The authority having jurisdiction shall be consulted as to the means by which a reserve supply of foam concentrate shall be made available.
4.4.2* The reserve supply shall be listed for use with system components.
4.5 Preprimed Systems.*
4.5.1 Wet pipe foam water systems shall be preprimed with foam water solution.
4.5.2 Systems shall not be required to be preprimed where recommended by the foam concentrate manufacturer and where approved by the authority having jurisdiction.
4.6 Approvals.
4.6.1 Prior to designing a system for consideration, the authority having jurisdiction shall be consulted.
4.6.2 All plans and specifications for the installation shall be approved by the authority having jurisdiction prior to installation, and such authority shall be consulted as to devices
5.4.1 Balanced pressure or positivepr essure injection shall be the preferred methods for introduction of foam concentrates into the water flowing through the supply piping to the system.
5.4.2* Balanced pressure injection methods shall be one of the following:
(1) A balance pressure proportioning system utilizing a foam concentrate pump discharging through a metering orifice into a proportioning controller with the foam concentrate and water pressures automatically maintained as equal by the use of a pressure balancing valve.
(2) A balanced pressure proportioning system utilizing a pressure proportioning tank with a diaphragm or bladder to separate the water and foam concentrate discharging through a metering orifice into a proportioning controller.
(3) An in line balanced pressure proportioning system utilizing a foam concentrate pump or bladder tank. A pressure regulating device placed in the pump return line shall maintain constant pressure in the foam concentrate supply line at all design flow rates. This constant pressure shall be greater than the maximum water pressure under all operating conditions.
(4) Foam concentrate pump discharging through a metering orifice into the protection system riser with the foam pressure at the upstream side of the orifice exceeding the water pressure in the system riser by a specific design value.
5.4.3 Other listed methods for foam proportioning shall be permitted as follows:
(1) Balanced positivepr essure injection systems utilizing a foam concentrate pump and drive motor that vary the foam concentrate pump output to match water flow rates while maintaining the correct percentage of foam concentrate
(2) Around thepum p proportioners
(3)* In line eductors (inductors)
5.4.4* Orifice plates shall have telltale indicators giving orifice diameters and indication of flow direction if flow characteristics vary with flow direction.
5.5 Foam Concentrate Pumps.*
5.5.1 Materials.
5.5.1.1* The design and materials of construction for foam concentrate pumps shall be approved for use with the type of foam concentrate used in the system.
5.5.1.2 Special attention shall be paid to the type of seal or packing used.
5.5.2 Rated Capacities.
5.5.2.1 Foam concentrate pumps shall have rated capacities at or in excess of the maximum system demand.
5.5.2.2 To ensure positive injection of foam concentrate, the discharge pressure ratings of pumps at the design discharge capacity shall be in excess of the maximum water pressure available under any condition at the point of foam concentrate injection.
5.5.3 Overpressurization.
5.5.3.1* Foam concentrate pumps capable of overpressurizing the system shall be provided with means of pressure relief from the discharge to the supply side of the pump to prevent excessive pressure and temperature.
5.5.3.2 Overpressure shall not exceed the working pressure of the foam concentrate piping system.
5.5.4 Flushing.
5.5.4.1* Foam concentrate pumps shall have means for flushing.
5.5.4.2 Foam concentrate pumps shall be provided with a drain cock or valve.
5.5.5 Foam concentrate pumps shall be automatics tarting upon system actuation.
5.5.6 Pumps shall be listed for this service in accordance with NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection.
5.6 Power Supply and Controller.
The power supply and controllers for the drivers of foam concentrate pumps shall be installed in accordance with NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection , and NFPA 70, National Electrical Code.
5.7 Foam Concentrate Storage Tanks.
5.7.1 Storage tanks for foam concentrates shall be constructed of materials compatible with the liquid, shall be solidly mounted, and shall be permanently located.
5.7.2 The storage temperatures for which foam concentrates are listed shall be considered the temperature limits for location of storage tanks.
5.7.3 AtmosphericType Storage Tanks.
5.7.3.1 Storage tanks shall have capacities to accommodate the needed quantities of foam concentrate plus space for thermal expansion.
5.7.3.2 Foam concentrate outlets from the tanks shall be located to prevent sediment from being drawn into the system.
5.7.3.3 When determining the quantity of foam concentrates, the volume of the sediment pocket shall be added to the quantity needed for system operation.
5.7.3.4* Tanks shall be equipped with conservation type vents, access handholes, or manholes that are located to provide for inspection of the following:
(1) Interior tank surfaces
of open basket area to inlet pipe size of at least 10:1 shall be used.
5.11.3.2 Strainers shall be capable of removing all solids of a size that would obstruct system components.
5.11.3.3 Perforations shall be no larger than the smallest orifice in the system and no less than in. (3.2 mm).
5.11.3.4 Strainers shall be installed so as to be accessible for cleaning (flushing) while maintaining system discharge during an emergency.
5.12 Automatic System Detection.
5.12.1 Detection required for foam water deluge systems shall be in accordance with NFPA 15, Standard for Water Spray Fixed Systems for Fire Protection.
5.12.2 Detection required for foam water preaction systems shall be in accordance with NFPA 13, Standard for the Installation of Sprinkler Systems.
5.13 Supervision.
5.13.1* Main water, foam concentrate, and foam solution valves shall be supervised by one of the following methods:
(1) Central station, proprietary, or remote station signaling service
(2) Local signaling service that will cause the sounding of an audible signal at a constantly attended location
(3) Valves locked in the open position
(4) Valves located within fenced enclosures under the control of the owner, sealed in the open position, and inspected weekly as part of an approved procedure
5.13.2 Detection and actuation circuitry shall be supervised through a listed panel in accordance with NFPA 72 , National Fire Alarm Code.
5.14 Test Connections.*
System test connections shall be sized to accommodate both the low flow of the proportioner and the maximum anticipated flow through the proportioner.
Chapter 6 Water Supplies
6.1 Water Quality.*
6.1.1 Water supplied to foam water systems shall be compatible with the foam concentrate to be used.
6.1.2 Water that contains solids likely to clog orifices in discharge devices but that is otherwise acceptable for making foam shall be permitted to be used after passing through line strainers.
6.2 Water Supply Capacity, Pressure, and Duration.
6.2.1 Water supplies for deluge foam water sprinkler systems and foam water spray systems shall be automatic.
6.2.1.1 Water supplies shall be of a capacity and a pressure that are capable of maintaining foam discharge or water discharge, or both, at the design rate for the required period of discharge over the entire area protected by systems expected to operate simultaneously.
6.2.2* Where the water supply is dependent on public water sources, attention shall be given to the pollution hazard introduced by the use of foam concentrate.
6.2.2.1 Cross connections shall be reviewed by public health agencies concerned.
6.2.3 Duration.
6.2.3.1* Water supplies shall be designed to supply the system at the design discharge rate and pressure for at least 60 minutes.
6.2.3.2 Water supplies for aircraft hangars shall be in accordance with NFPA 409, Standard on Aircraft Hangars.
6.2.4* Unless the requirements of 6.2.4.1 or 6.2.4.2 are met, the fire department connection(s) shall consist of two 2½ in. (65 mm) NH internal threaded swivel fitting(s) with connections using “2.5 7.5 NH standard thread,” as specified in NFPA 1963, Standard for Fire Hose Connections. [ 13: 6.8.1]
6.2.4.1 Where local fire department connections do not conform to NFPA 1963, Standard for Fire Hose Connections , the authority having jurisdiction shall be permitted to designate the connection to be used. [ 13: 6.8.1.1]
6.2.4.2 The use of threadless couplings shall be permitted where required by the authority having jurisdiction and where listed for such use. [ 13: 6.8.1.2]
6.2.4.3 Fire department connections shall be equipped with listed plugs or caps, properly secured and arranged for easy removal by fire departments. [ 13: 6.8.2]
6.2.4.4 Fire department connections shall be of an approved type. [ 13: 6.8.3]
6.2.5 Fire Department Connection.
6.2.5.1* When a fire department connection is required, it shall be installed on the supply side of the proportioner.
6.2.5.2 Where a fire department connection is provided, the following items shall be evaluated before installation or use:
(1) Overpressurizing of system components
(2) Imbalance of proportioning equipment
(3) Dilution of proportioned foam solution
