© 2016 Fire Protection Research Foundation

1 Batterymarch Park, Quincy, MA 02169-7417, USA Email: foundation@nfpa.org | Web: nfpa.org/foundation

Fire Department Connection (FDC) Inlet Flow Assessment FINAL REPORT BY:

Y. Pock Utiskul, Ph.D., Neil P. Wu, P.E., and Elizabeth Keller Exponent, Inc. Bowie, Maryland, USA January 2016

 

FOREWORD A Fire Department Connection (FDC) is “A connection through which the fire department can pump supplemental water into the sprinkler system, standpipe, or other system, furnishing water for fire extinguishment to supplement existing water supplies.” FDCs are required on all standpipe systems per NFPA 14, Standard for the Installation of Standpipe and Hose Systems, and sprinkler systems per NFPA 13, Standard for the Installation of Sprinkler Systems. In 2007, the Technical Committee for NFPA 14 added the requirement for one 2 ½ inch inlet per every 250 gallons per minute (gpm), but this requirement lacks supporting scientific documentation, so there was a need to conduct flow testing to determine the amount of water that is possible to flow into an FDC inlet.

The Fire Protection Research Foundation initiated this project to determine the actual flow that can be achieved for each 2 ½ inch inlet on an FDC to provide technical basis to the NFPA 14 Technical Committee for a possible change to the standard. The Fire Protection Research Foundation expresses gratitude to the report authors Y. Pock Utiskul, Ph.D., Neil P. Wu, P.E., and Elizabeth Keller who are with Exponent, Inc. The Foundation also expresses gratitude to the Maryland Fire and Rescue Institute (MFRI) where the tests were conducted. The Research Foundation appreciates the guidance provided by the Project Technical Panelists and all others that contributed to this research effort. Thanks are also expressed to the National Fire Protection Association (NFPA) for providing the project funding through the NFPA Research Fund. The content, opinions and conclusions contained in this report are solely those of the authors and do not necessarily represent the views of the Fire Protection Research Foundation, NFPA, Technical Panel or Sponsors. The Foundation makes no guaranty or warranty as to the accuracy or completeness of any information published herein.

 

About the Fire Protection Research Foundation

The Fire Protection Research Foundation plans, manages, and communicates research on a broad range of fire safety issues in collaboration with scientists and laboratories around the world. The Foundation is an affiliate of NFPA.

About the National Fire Protection Association (NFPA)

Founded in 1896, NFPA is a global, nonprofit organization devoted to eliminating death, injury, property and economic loss due to fire, electrical and related hazards. The association delivers information and knowledge through more than 300 consensus codes and standards, research, training, education, outreach and advocacy; and by partnering with others who share an interest in furthering the NFPA mission. All NFPA codes and standards can be viewed online for free. NFPA's membership totals more than 65,000 individuals around the world. Keywords: fire department connection, FDC, FDC inlet, flow testing, standpipe systems, NFPA 14

 

PROJECT TECHNICAL PANEL

Scott Futrell, Futrell Fire Consult & Design, Inc.

Dave Hague, Liberty Mutual

Jeff Hebenstreit, UL LLC

Steve Leyton, Protection Design & Consulting (AFSA representative)

Bob Morgan, Fort Worth Fire Department

Maurice Pilette, Mechanical Designs Ltd

Pete Schwab, Wayne Automatic Fire Sprinklers

Kyle Smith, Cobb County Fire and Emergency Services

Ronald Webb, S.A. Comunale Company, Inc. (NFSA representative)

Chad Duffy, NFPA Staff Liaison

PROJECT SPONSOR

National Fire Protection Association

Thermal Sciences

Fire Department Connection Inlet Flow Requirements: A Report on Full-scale Testing Results

1505254.000 7849

Fire Department Connection Inlet Flow Requirements: A Report on Full-scale Testing Results Prepared for Fire Protection Research Foundation One Batterymarch Park Quincy, MA 02169 Prepared by Y. Pock Utiskul, Ph.D., P.E., CFEI Neil P. Wu, P.E., IAAI-CFI, CBO Elizabeth Keller Exponent, Inc. 17000 Science Drive, Suite 200 Bowie, MD 20715 January 8, 2016 Exponent, Inc.

January 8, 2016

1505254.000 7849 ii

Contents

Page

List of Figures iv 

List of Tables vi 

Acronyms and Abbreviations vii 

Limitations viii 

Executive Summary ix 

1  Background 1 

1.1  Project History 1 

1.2  Research Objectives and Project Scope 1 

1.2.1  Review of Source Material for the Traditional Flow Requirement 2 

1.2.2  Development of Full-Scale Flow Test Plan 2 

1.2.3  Full-scale Flow Testing 3 

1.2.4  Report and Summary of Best Practices 3 

1.3  Project Assumptions 3 

2  Literature Review 4 

2.1  Current FDC Requirements 4 

2.2  History of the NFPA 14 Requirement 5 

2.3  Jurisdictional Adoptions and Procedures 6 

2.3.1  Code Adoptions 7 

2.3.2  Standpipe Firefighting Operations 10 

2.4  Existing FDC Flow Test Data 11 

2.5  Summary 12 

3  Testing Program Summary 14 

4  FDC Descriptions 16 

4.1  Single FDCs 16 

4.2  Siamese FDCs 17 

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4.3  Triamese FDC 17 

5  Test Setup 23 

5.1  Test Apparatus 24 

5.1.1  Water Flow Activities 24 

5.1.2  Supply Hose Line 28 

5.1.3  Flow Test Assembly 28 

5.1.4  Flow Rate Measurements 31 

5.1.5  Pressure Loss Measurements 32 

5.1.6  DAQ System 33 

5.1.7  Still Photography and High Definition Video 33 

5.2  Flow Test Protocols 33 

6  Test Results 35 

7  Analysis and Discussion 40 

7.1  Single FDC 40 

7.2  Siamese FDC 41 

7.3  Triamese FDC 43 

7.4  FDCs Pressure Loss Characteristics 44 

7.5  Section Summary 47 

8  Key Findings 48 

9  Acknowledgements 50 

Appendix A 51 

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List of Figures

Page

Figure 1 Map of municipalities included in survey 6 

Figure 2 Single FDCs 17 

Figure 3 Single flush FDC (FDC-1) 18 

Figure 4 Single flush FDC (FDC-2) 18 

Figure 5 Single flush FDC (FDC-3) 19 

Figure 6 Siamese freestanding FDC (FDC-4) 19 

Figure 7 Siamese freestanding FDC (FDC-4); view from bottom showing single clapper 20 

Figure 8 Siamese projecting FDC (FDC-5) 20 

Figure 9 Siamese projecting FDC (FDC-5); view through outlet showing double inlet clappers 21 

Figure 10 Triamese flush FDC (FDC-6) 21 

Figure 11 Triamese flush FDC (FDC-6); view through inlet showing clappers 22 

Figure 12 Fire department pumper apparatus 25 

Figure 13 Test facility and drafting basin at MFRI 26 

Figure 14 Test platform with single FDC and test apparatus secured to test platform 26 

Figure 15 Test platform with siamese FDC and test apparatus secured to test platform 27 

Figure 16 Test platform with triamese FDC and test apparatus secured to test platform 27 

Figure 17 Flow test schematic for single FDC 29 

Figure 18 Flow test schematic for siamese FDC 29 

Figure 19 Flow test schematic for triamese FDC 30 

Figure 20 Flow rate measurement with in-line averaging pitot tube 31 

Figure 21 Single FDC flow test 36 

Figure 22 Siamese FDC flow test 36 

Figure 23 Triamese FDC flow test 37 

Figure 24 Measurement layout 37 

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Figure 25 Single FDC pressure loss data 40 

Figure 26 Siamese FDC pressure loss data 42 

Figure 27 Triamese FDC pressure loss data 44 

Figure 28 FDC pressure loss characteristics 46 

Figure 29 Pumper control and pressure gauges 53 

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List of Tables

Page

Table 1 Test Matrix 15 

Table 2 FDC Descriptions 16 

Table 3 Test Measurement Results 38 

Table 4 FDC Pressure Loss Coefficients 45 

Table 5 Pressure Data 51 

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Acronyms and Abbreviations

CFC California Fire Code

DAQ data acquisition system

FDC fire department connection

FM FM Global

FPRF Fire Protection Research Foundation

ft feet

gpm gallons per minute

hz hertz

in inch

IBC International Building Code

ICC International Code Council

IFC International Fire Code

lb pound

MFRI Maryland Fire and Rescue Institute

NFPA National Fire Protection Association

NH American National Fire Hose Screw Threads

NPT National Pipe Threads

SCH schedule

SOP standard operating procedures

UL Underwriters Laboratories

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Limitations

At the request of the Fire Protection Research Foundation (FPRF), Exponent assessed fire

department connection (FDC) inlet flow requirements. This report summarizes a literature

review and full-scale flow testing of multiple types of FDCs. The scope of services performed

during this literature review and testing program may not adequately address the needs of other

users of this report, and any re-use of this report or its findings, conclusions, or

recommendations presented herein are at the sole risk of the user.

The full-scale flow test strategy and any recommendations made are strictly limited to the test

conditions included and detailed in this report. The combined effects (including, but not limited

to) of different environmental conditions, equipment, and scenarios are yet to be fully

understood and may not be inferred from these test results alone.

The findings formulated in this review are based on observations and information available at

the time of writing. The findings presented herein are made to a reasonable degree of scientific

and engineering certainty. If new data becomes available or there are perceived omissions or

misstatements in this report, we ask that they be brought to our attention as soon as possible so

that we have the opportunity to fully address them.

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Executive Summary

This report summarizes full-scale flow testing of multiple types of FDCs. For an automatic

standpipe, an FDC is defined as, “A connection through which the fire department can pump the

secondary water supply to an automatic standpipe system at the required system demand.

Supplemental water can also be provided into the sprinkler system or other system furnishing

water for fire extinguishment to supplement existing water supplies.”1 In the case of a manual

standpipe, the FDC is defined as, “A connection through which the fire department can pump

the primary water supply to a manual standpipe system at the required system demand.”2

Industry standards, such as National Fire Protection Association (NFPA) 14, Standard for the

Installation of Standpipe and Hose Systems, and NFPA 13, Standard for the Installation of

Sprinkler Systems, require FDCs be installed on standpipe systems and automatic sprinkler

systems, respectively.

Since 2007, NFPA 14 has required one (1) 2.5-inch diameter FDC inlet for every 250 gallons

per minute (gpm) of water flow to satisfy the standpipe system demand; however, there is

currently a lack of supporting scientific documentation to substantiate this flow limitation per

inlet. Flow testing to characterize the maximum actual flow rate that can be achieved for each

2.5-inch FDC inlet is required to support the current 250 gpm requirement or recommend a

change to the standard.

In summary, this project involved full-scale flow testing of multiple FDCs to determine actual

flow characteristics and pressure loss associated with various FDC assemblies. The tests

utilized suppression equipment consistent with real-world installations in structures and typical

procedures for emergency response to a structure fire, including the use of a fire department

pumper apparatus and hose to connect and flow water through the FDC assemblies.

1 NFPA 14-2013, Section 3.3.3.1.1. 2 NFPA 14-2013, Section 3.3.3.1.2.

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The overriding goal of this research project was to provide a technical basis to the NFPA 14

Technical Committee for a possible change to the standard. A full listing of project

observations as they relate to the current NFPA guidance is provided in Section 8 of this report.

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1 Background

1.1 Project History

For an automatic standpipe, a fire department connection (FDC) is defined as, “A connection

through which the fire department can pump the secondary water supply to an automatic

standpipe system at the required system demand. Supplemental water can also be provided into

the sprinkler system or other system furnishing water for fire extinguishment to supplement

existing water supplies.”3 In the case of a manual standpipe, the FDC is defined as, “A

connection through which the fire department can pump the primary water supply to a manual

standpipe system at the required system demand.”4 Industry standards, such as National Fire

Protection Association (NFPA) 14, Standard for the Installation of Standpipe and Hose

Systems, and NFPA 13, Standard for the Installation of Sprinkler Systems, require FDCs be

installed on standpipe systems and automatic sprinkler systems.

Since 2007, NFPA 14 has required one (1) 2.5-inch diameter FDC inlet for every 250 gallons

per minute (gpm) of water flow to satisfy the standpipe system demand; however, there is

currently a lack of supporting scientific documentation to substantiate this flow limitation per

inlet. Flow testing to characterize the maximum actual flow rate that can be achieved for each

2.5-inch FDC inlet is required to support the current 250 gpm requirement or recommend a

change to the standard.

1.2 Research Objectives and Project Scope

The overall project research objective was to provide a technical basis to the NFPA 14

Technical Committee for a possible change to the standard.

The scope of work included, but was not limited to, the following primary tasks:

1. A review of any source material for the traditional 250 gpm flow limitation for each 2.5-

inch diameter FDC inlet (see Section 2);

3 NFPA 14-2013, Section 3.3.3.1.1. 4 NFPA 14-2013, Section 3.3.3.1.2.

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1505254.000 7849 2

2. Development of a full-scale test plan for flow testing to characterize the flow of water

into a 2.5-inch diameter inlet(s) on an FDC (see Sections 3 through 5);

3. Full-scale flow testing per the full-scale flow testing plan developed above, including

three separate types of FDCs (see Section 6); and

4. Report of final results and summary of recommendation(s) to the NFPA 14 Technical

Committee for the actual flow expected into a 2.5-inch FDC inlet, as well as the pressure

loss characteristics of the FDC.

A more detailed description of the tasks performed by Exponent to fulfill the project objectives

is provided below.

1.2.1 Review of Source Material for the Traditional Flow Requirement

Exponent collected, reviewed, and summarized available source material for the traditional 250

gpm flow limitation for each 2.5-inch diameter FDC inlet. This task included a review of

historical records documenting any proposed additions or changes to the relevant industry

standards (e.g., NFPA 13 and NFPA 14) in relation with the 250 gpm and 2.5-inch diameter

FDC inlets, as well as a review of the current standard operating procedures (SOPs) and/or code

requirements for the number of FDCs required by municipalities in varying regions throughout

the United States (see Section 2).

1.2.2 Development of Full-Scale Flow Test Plan

Exponent, in conjunction with the Project Technical Panel, developed an comprehensive

program for full-scale flow testing to characterize the flow of water into a 2.5-inch diameter

inlet on an FDC following the SOP established in NFPA 13E, Recommended Practice for Fire

Department Operations in Properties Protected by Sprinkler and Standpipe Systems. The

testing utilized a fire department pumper and standard hose to connect to the inlet(s) of multiple

types of FDCs instrumented with flow measuring devices to determine how much flow can be

achieved as a function of the pressure loss.

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1.2.3 Full-scale Flow Testing

The full-scale flow testing involved testing of multiple FDCs installed on a test manifold. All

tests utilized actual suppression equipment and procedures, including a fire department pumper

apparatus and hose. All water flow activities were conducted by qualified active duty

firefighters. Exponent collaborated with the Maryland Fire and Rescue Institute (MFRI), who

provided their facilities and expertise. Their training staff was utilized to provide technical

insight on standard FDC connection procedures and to facilitate the tests. Active duty

firefighters from MFRI performed all water flow activities.

1.2.4 Report and Summary of Best Practices

Exponent collected and processed the test data from the full-scale testing program in this formal

research engineering report. This report provides:

1. An overview of the project work to date;

2. A summary of the full-scale test data;

3. Comparison with current NFPA guidance; and

4. Identification of future potential research.

1.3 Project Assumptions

The following are key assumptions and limitations related to the test program:

The FDCs procured for this test program are only a small set of samples intended to

provide a preliminary understanding of FDC hydraulic characteristics (i.e., flow and

pressure loss) in a broad range of FDC configurations. The test results from this study

are not intended to be representative of all FDCs available or used in systems.

FDC flow rate data obtained from this test is specific to the upstream supply line

configuration and components used in this test program (i.e., hoses and fittings).

These upstream supply components, including the fire department pumper, are typical

equipment used during fire department operations. Friction losses associated with the

upstream equipment are well documented.

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2 Literature Review

2.1 Current FDC Requirements

FDC requirements are currently defined by NFPA 14 for standpipe systems and NFPA 13 for

sprinkler systems. The purpose of a standpipe system is to eliminate the need for excessively

long runs of hose for manual firefighting inside a structure. Standpipes allow firefighters to

connect a hose to a permanently installed valve on the standpipe system inside a building and

fight a fire with a shortened amount of hose. FDCs allow firefighters to supplement, or fully

supply, the standpipe water flow from an external water source, such as a hydrant or pond,

through a pumper apparatus to the structure. The current (2013) edition of NFPA 14 requires

that the full standpipe system demand be available from FDCs, and states in Section 7.12.3:

Fire department connection sizes shall be based on the standpipe system demand and

shall include one 2 1⁄2 in. (65 mm) inlet per every 250 gpm (946 L/min).

In contrast, for sprinkler systems, the current (2013) edition of NFPA 13 states in Section 6.8.1,

that FDC(s) shall consist of two (2) 2.5-inch inlets, unless otherwise designated by the Authority

Having Jurisdiction (AHJ), or where piped to a 3-inch or smaller riser.5 Further clarification is

provided in the annex, which states that the purpose of the FDC is to supplement the water

supply, but not necessarily provide the entire sprinkler system demand. NFPA 13-2013 further

states that FDCs are not intended to deliver a specific volume of water.6

The FDC requirements in NFPA 14 are more explicit than the requirements in NFPA 13 and

specifically call for FDCs to have one (1) 2.5-inch diameter hose connection for each 250 gpm

of system demand. A typical standpipe system in a fully sprinkler protected facility may need

up to four (4) FDC inlets to satisfy the system demand. Where adopted, the requirements of

both standards must be met, including those requiring the more restrictive FDC capacity of 250

gpm for every 2.5-inch diameter inlet in a combined sprinkler/standpipe system.

5 NFPA 13-2013 Section 6.8.1 6 NFPA 13-2013 Section A.6.8.1

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NFPA 14 also requires manual standpipe systems be designed to provide 100 psi at the topmost

outlet, with hydraulic calculations terminating at the FDC.7 The intent of the standard is for a

fire department pump to be the source of flow and pressure8, however, pressure loss values for

the FDC itself are not provided in the standard and data from the manufacturers is currently

unavailable (see Section 2.4).

Although not directly related to FDC inlet flow, the 2016 edition of NFPA 20, Installation of

Stationary Pumps for Fire Protection, offers an interesting correlation of flow (pump rating in

gpm) to the number of hose valve outlets required. For pumps rated from 100 to 1,000 gpm, the

number of outlets required approximately follows a similar 250 gpm per 2.5-inch valve ratio as

prescribed in NFPA 14, however, there is more variability at certain higher flows (above 1,250

gpm), where greater than 250 gpm is allowed per each 2.5-inch diameter valve.9

2.2 History of the NFPA 14 Requirement

The current FDC requirement in Section 7.12.3 of NFPA 14 first appeared in the Report on

Proposals for the 2007 edition of the standard. The substantiation of the request states that the

proposal is the result of the Standpipe Task Group, which met in June 2004 and forwarded its

recommendations to the Technical Committee on Standpipes for action.10,11 Since it first

appeared in the 2007 edition of NFPA 14, Section 7.12.3 has resulted in proposals to remove the

restriction based on manual standpipe pumper tests that indicate 2.5-inch diameter inlets on an

FDC are capable of significantly more flow.12 One response to a proposal to modify the section

states that the restriction is intended to simplify and assist contractors in understanding how

many inlets to provide for firefighting operations, not just for testing.13 The 2.5-inch inlet flow

requirement of 250 gpm is understood to be a conservative value under ideal delivery conditions

and allows for redundancy for firefighting operations in the event that an FDC is lost.14 Other

7 NFPA 14-2013 Section 7.8.1.2. 8 NFPA 14-2013 Section A.7.8.1.2. 9 NFPA 20-2016 Table 4.27(a). 10 NFPA 14 Report on Proposals 2005, 14-58 Log #47. 11 Minutes have been requested for the June 2004 meeting of the Standpipe Task Group. 12 NFPA 14 Report on Proposals 2012, 14-70 Log #16. 13 NFPA 14 Report on Comments 2012, 14-35 Log #38. 14 NFPA 14 Report on Proposals 2012, 14-70 Log #16.

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reasons for the fixed inlet flow requirement include the anticipation of pressure loss possible

due to the location of fire hydrants and arrangement of supply hose from the hydrant to a

pumper and from the pumper to the FDC, including the distance traveled and elevation

changes.15

2.3 Jurisdictional Adoptions and Procedures

A survey of several major municipalities in varying regions throughout the United States was

conducted to determine their current code adoptions relative to standpipe systems and specific

requirements for number of FDC inlets serving standpipe systems, as shown in Figure 1. In

addition, literature was reviewed to determine the most common arrangement for equipment

supplying an FDC.

Figure 1 Map of municipalities included in survey

15 NFPA 14 Report on Comments 2012, 14-34 Log #9.

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2.3.1 Code Adoptions

2.3.1.1 Los Angeles, California

The 2014 City of Los Angeles Fire Code adopts portions of the California Fire Code (CFC) and

the 2012 edition of the International Code Council (ICC) International Fire Code (IFC).16

Section 905.2 states that standpipe systems shall be installed according to an amended version

of NFPA 14-2013. The amended portion does not affect the requirements of Section 7.12.3.17

The current Los Angeles Municipal Code (6th edition) outlines the amendments to NFPA 14 and

the amended portion does not affect the requirements of Section 7.12.3.18 In addition to Section

7.12.3, the previous edition of the Los Angeles Municipal Code also mandated the number of

FDCs based on the height of the highest outlet above the FDC and the number of the standpipe

risers.19 This requirement no longer applies to new construction after January 2014.

2.3.1.2 New York, New York

The 2014 New York City Fire Code, Section 905.2, states that standpipe systems shall be

installed in accordance with the construction codes, including the Building Code.20 The 2014

New York City Building Code, Section 905.2, states that standpipe systems shall be installed

according to an amended version of NFPA 14-2007. The amended portion deletes Section

7.12.3.21 Instead, the New York City Administrative Code, Section 27-940, requires at least one

siamese connection, an FDC with two-way inlets, for each 300 feet of exterior building wall.

2.3.1.3 Chicago, Illinois

The Municipal Code of Chicago, Title 15, Fire Prevention, Section 15-16-1020, requires at least

one siamese connection on each street exposure, to a limit of two street exposures. If any

16 http://www.ecodes.biz/ecodes_support/free_resources/2014LACityFire/14Fire_main.html, Section 101, as of

September 21, 2015. 17 2014 Los Angeles Fire Code Chapter 80, Referenced Standards. 18 City of Los Angeles Municipal Code, 6th Edition, Ordinance No. 182847, Section 94.2020.0, NFPA 14. 19 City of Los Angeles Municipal Code, 5th Edition, Ordinance No. 179324, Section 94.2020.8, Table 4.8.2 20 http://www.nyc.gov/html/fdny/apps/pdf_viewer/viewer.html?file=firecode_chap_09.pdf&section=firecode_2014,

as of September 21, 2015 21 2014 New York City Building Code Appendix Q, Modified National Standard for Automatic Sprinkler,

Standpipe, Fire Pump and Fire Alarm Systems.

January 8, 2016

1505254.000 7849 8

exposure is more than 250 feet long, two siamese connections are required, spaced at least 200

feet apart.22

2.3.1.4 Atlanta, Georgia

The state of Georgia adopts State Minimum Fire Safety Standards, based on the 2012 edition of

the IFC, with modifications. Section 905.1 states that standpipe systems shall be installed in

accordance with NFPA 14-2013, as amended. The amended portion does not affect the

requirements of Section 7.12.3, however, a new section (7.12.4) is added that states that the

location of FDCs shall be approved by the Fire Chief.23

2.3.1.5 Orlando, Florida

The Orlando Building Code incorporates the 2014 Florida Building Code24, which is based on

the 2012 edition of the ICC International Building Code (IBC). Section 905.2 states that

standpipe systems shall be installed in accordance with the Florida Building Code and NFPA

14-2010.25 In addition, the City of Orlando Fire Prevention Code adopts NFPA 1, Uniform Fire

Code, Chapter 13, Fire Protection Systems, and amends Section 13.2.2.1 to state that two (2)

siamese connections shall be provided in the path of fire department access, one at each end of

the building or as remotely located as possible.26

2.3.1.6 Kansas City, Missouri

The Kansas City, Missouri Code of Ordinances adopts the 2012 edition of the IBC, with

amendments.27,28 Section 905.2 of the 2012 IBC states that standpipe systems shall be installed

in accordance with NFPA 14-2010. The amended portion does not affect the requirements of

NFPA 14 Section 7.12.3.

22 http://www.amlegal.com/nxt/gateway.dll/Illinois/chicagobuilding/buildingcodeandrelatedexcerptsofthemunic?

f=templates$fn=default.htm$3.0$vid=amlegal:chicagobuilding_il; Current through March 18, 2015. 23 Georgia Minimum Fire Safety Standards (Chapter 120-3-3), effective January 1, 2015. 24 Orlando, Florida Code of Ordinances, Supplement 57, Update 2, Chapter 13, Building Code. 25 Florida Building Code, Building, 5th Edition (2014), Chapter 35, Referenced Standards. 26 Orlando, Florida Code of Ordinances, Supplement 57, Update 2, Chapter 24, Fire Prevention Code, Section

24.27. 27 Kansas City, Missouri Code of Ordinances, Article II, Sec. 18-40. 28 The Kansas City, Missouri Code of Ordinances further adopts the 2000 edition of the IFC, with amendments, in

Sec. 26-100, however, the 2012 edition of the IBC is the more recent and restrictive adoption of NFPA 14, and therefore prevails.

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2.3.1.7 Fort Worth, Texas

The Fire Code of the City of Forth Worth adopts the 2009 edition of the IFC, with

amendments.29 Section 905.2 of the 2009 IFC states that standpipe systems shall be installed in

accordance with NFPA 14-2007. The amended portion does not affect the requirements of

NFPA 14 Section 7.12.3.

2.3.1.8 Seattle, Washington

The Seattle Building Code adopts the 2012 edition of the IBC, with amendments.30 Section

905.2 of the 2012 IBC states that standpipe systems shall be installed in accordance with NFPA

14-2010.

2.3.1.9 District of Columbia

The 2013 District of Columbia Fire Code is based on the 2012 edition of the IFC.31 Section

905.2 states that standpipe systems shall be installed according to NFPA 14-2010, with

exceptions. The exceptions do not affect the requirements of Section 7.12.3.32

2.3.1.10 Las Vegas, Nevada

The Municipal Code of the City of Las Vegas adopts the 2012 edition of the IFC, along with the

Southern Nevada Fire Code Amendments.33 Section 905.2 of the 2012 IFC states that standpipe

systems shall be installed according to NFPA 14-2010. The Southern Nevada Fire Code

Amendments change the requirements of Section 7.12.3 to address the sprinkler system demand

(if a combined system); however, they do not affect the inlet flow requirement of 250 gpm. The

requirements of 7.8.1.1 are changed to require manual standpipe systems be designed to provide

125 psi (instead of 100 psi) at the topmost outlet.34

29 Fort Worth Ordinance Number 19607-03-2011. 30 Seattle Municipal Code, Supplement 2, Update 2, Title 22, Subtitle I, Building Code. 31 http://www.ecodes.biz/ecodes_support/Free_Resources/2013DistrictofColumbia/13Fire/13DCFire_main.html, ,

as of September 21, 2015 32 2013 District of Columbia Fire Code, Chapter 80, Referenced Standards. 33 Municipal Code of the City of Las Vegas, Supplement 23, Title 16, Chapter 16.16, International Fire Code. 34 2014 Southern Nevada Fire Code Amendments.

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2.3.2 Standpipe Firefighting Operations

A review of the literature revealed that there is scarce information currently published regarding

the arrangement and connection of hose from the water source, through a fire department

pumper apparatus, to an FDC. A research study by the U.S. Fire Administration recommends

that fire departments have water supply SOPs that establish which units are responsible for

supplying FDCs, possibly including special pumping procedures. The study cites one SOP that

includes details for water supply operations: Dallas, Texas specifies that two pumpers supply

the standpipe system for redundancy or in case higher pressure is required. Dallas also does not

allow the use of “large diameter hose” to connect the pumper to the standpipe.35

There are many studies detailing standpipe operations, however, they focus on the building

interior connections and the attack hose and nozzle configurations. A research study by the

Oakland Fire Department aimed at updating their high-rise firefighting procedures surveyed ten

(10) major municipalities and determined that a majority of the fire departments surveyed use a

2.5-inch hose with a 1 1/8-inch smooth bore nozzle for standpipe operations, however, some use

a 1 ¾-inch hose with a 7/8-inch smooth bore nozzle. The research study further determined that

a high-rise building standpipe system must be augmented by fire apparatus for effective

firefighting practices.36 A similar research study performed by the New Orleans Fire

Department surveyed 12 major municipalities and found that most departments surveyed only

have a casual reference to water supply operations in their SOPs, which instructs the first due

engine to connect to the FDC and supply the system with “appropriate pressure.” Field tests

conducted during the same research study determined that a 1,250 gpm dual stage pump in a

pumper apparatus could develop outlet pressures of 200 to 600 psi.37

The 2015 edition of NFPA 13E provides basic procedures and information for use in fire

department operations involved with automatic sprinkler and standpipe systems. Figure 4.3.4(b)

specifies a minimum 2.5-inch hose to supply the FDC from the pumper for supplementing an

35 U.S. Fire Administration/Technical Report Series, “Special Report: Operational Considerations for Highrise

Firefighting.” USFA-TR-082/April 1996. 36 Edwards, J. “High-Rise Firefighting: An Analysis of Procedures for Operational Effectiveness.” Oakland Fire

Department, Oakland, CA. 37 Savelle, G. “Fire Department High Pressure Pumping Operations at High-Rise Fires.” New Orleans Fire

Department, New Orleans, LA.

January 8, 2016

1505254.000 7849 11

automatic sprinkler system; however, a minimum hose diameter is not specified for standpipe

operations. Instead, Section 6.3.3 states that lines from a pumper should be connected and

charged to the pressure required to give the desired working pressure on the standpipe outlets

being used. In addition, Section 6.3.4.1 states that the pump operator should consider the

following factors in calculating the pump discharge pressure:

Friction loss in the hose supplying the FDC;

Friction loss in the standpipe system itself;

Pressure loss due to the elevation of the nozzles;

The number and details of the attack lines operating from the standpipe; and

The pressure desired at the nozzles.

Pressure losses for fire hoses of various lengths and diameters are well characterized and

documented38, allowing the supply hose diameter to be chosen based on the needs of the fire

department.

2.4 Existing FDC Flow Test Data

Data sheets from six (6) FDC manufacturers were reviewed for existing flow test data or friction

loss information. Of the approximately 30 models reviewed (most with multiple configurations,

i.e., clappers, inlet arrangement, etc.), none currently provide any flow test data or friction loss

information. Most provide (minimum) inlet flow capacities in line with the NFPA 14

requirement for one (1) 2.5-inch diameter inlet per 250 gpm of flow. Three manufacturers

provided pressure ratings on at least one FDC, ranging from 175 to 500 psi.

FDC data sheets generally referenced listings from Underwriters Laboratories (UL) and/or

approval by FM Global (FM). UL 405, Standard for Fire Department Connection Devices, was

reviewed and references NFPA 14 for the installation of FDCs for standpipe systems. UL 405

does not provide flow test data; however, it does specify that FDCs are tested to 300 psig for

38 Scheffey, J.L., et al., Determination of Fire Hose Friction Loss Characteristics, The Fire Protection Research

Foundation, October 2013.

January 8, 2016

1505254.000 7849 12

leakage and strength of body. 39 In addition, FM 1530, Approval Standard for Fire Department

Connections, was reviewed and also does not provide flow test data; however, it specifies that

the minimum rated working pressure shall be 175 psig.40

2.5 Summary

FDCs allow firefighters to supplement, or fully supply, the standpipe water flow from an

external water source, such as a hydrant or pond, through a pumper apparatus to a structure.

NFPA 14 requires that the full standpipe system demand be available from FDCs and requires

one (1) 2.5-inch diameter inlet for every 250 gpm of standpipe demand. The FDC requirements

in NFPA 14 are more prescriptive than those in NFPA 13. In a combined sprinkler/standpipe

system, the more restrictive requirements of NFPA 14 generally apply. In addition, NFPA 14

requires manual standpipe systems be designed to provide 100 psi at the topmost outlet, with

hydraulic calculations terminating at the FDC, however, pressure loss values for the FDC itself

are not provided in the standards and data from the manufacturers is currently unavailable.

Several major municipalities in varying regions throughout the United States were surveyed to

determine their current code adoptions relative to standpipe systems and specific requirements

for number of FDC inlets serving standpipe systems. Of the 10 municipalities surveyed, the

majority adopt NFPA 14 with no modification of the default NFPA 14 FDC inlet flow

requirements. Municipalities that do not adopt NFPA 14 requirements generally use the number

of exposures and length of the building exposure side to determine the number of FDCs

required.

While the current NFPA requirements do not include the number and the length of the building

exposure sides as a factor to determine the number of required FDCs, it is recognized that

certain jurisdictions highlight the need for redundancy of FDCs by taking the building exposures

into consideration. Based on this information, redundancy appears to be an important factor for

overall system reliability.

39 UL 405, 6th Edition, August 23, 2013. 40 FM 1530, August 1970.

January 8, 2016

1505254.000 7849 13

In addition, literature was reviewed to determine the most common arrangement for equipment

supplying an FDC. Although there is a lack of information specific to water supply operations

at high-rise structure fires, it was determined that pressure losses for fire hoses of various

lengths and diameters are well characterized and documented, allowing pressure loss of the

FDC component to be calculated independent of the upstream supply components.

January 8, 2016

1505254.000 7849 14

3 Testing Program Summary

Exponent, with guidance from the Project Technical Panel, conducted a series of flow tests on

common FDCs with the following goals: 1) to determine the maximum flow rate that can be

achieved for each 2.5 inch diameter inlet and 2) to measure the pressure losses associated with

the FDCs as a function of flow rate. Three common types of FDCs were acquired for this test

program, including single, siamese (two-way inlets), and triamese (three-way inlets). A more

detailed description of each acquired FDC is provided in Section 4.

A fire department pumper, Model 2011 Pierce Arrow XT, rated at 2,000 gpm capacity with a

minimum net pressure of 150 psi was utilized to supply water flow from a municipal fire

hydrant. Each FDC inlet was connected via a standard 2.5-inch diameter hose with a 100-foot

length (two 50-foot sections). A pressure transducer was instrumented upstream of each FDC

inlet. Downstream of the FDC outlet, an in-line averaging pitot tube was instrumented to obtain

the total flow rate as well as the pressure loss across the FDC assembly. With the exception of

pressure readings on the supply hoses from the fire department pumper and the differential

pressure on the in-line averaging pitot tube, all pressure measurements were recorded via a data

acquisition system to allow for real-time monitoring of the flow condition to ensure pressure

data during the steady state flow conditions were captured at a target flow rate.

For each flow test, water was charged to the FDC inlet(s) starting from a low flow condition to

develop bulk flow (no greater than 150 gpm), then gradually increased to a target flow rate for

the FDC assembly as outlined in the test matrix (see Table 1). Where multiple FDC inlets were

tested simultaneously, the flow was equally distributed to each inlet. At the respective target

flow rate, a minimum of 2 minutes was allowed for a steady state condition to develop. After a

maximum flow was reached, the flow was gradually decreased to a lower target flow rate and

the measurements were repeated. The achievement of the maximum flow was determined based

on the flow capacity available of from the hydrant, as well as the general safety observations

during the test. As a safety precaution, due to a potential for high velocity flow, it was

January 8, 2016

1505254.000 7849 15

determined that the theoretical maximum flow was approximately 750 gpm per each 2.5-inch

diameter FDC inlet (three times the current prescriptive requirement of 250 gpm).41

A detailed description of the test apparatus setup, measurements, and the test protocols is

provided in Section 5.

Table 1 Test Matrix

Test No.

FDC ID FDC Type Test ID* Flow to Inlet

Number Target Flow [gpm]

1 FDC-1 Single FDC-1-1 1 250, 500, Max

2 FDC-2 Single FDC-2-1 1 250, 500, Max

3 FDC-3 Single FDC-3-1 1 250, 500, Max

4 FDC-4 Siamese

FDC-4-1 1 250, 500, Max

5 FDC-4-2 1 and 2 500, 1000, Max

6 FDC-5 Siamese

FDC-5-1 1 250, 500, Max

7 FDC-5-2 1 and 2 500, 1000, Max

8

FDC-6 Triamese

FDC-6-1A 1 250, 500, Max

9 FDC-6-1B 2 (center inlet) 250, 500, Max

10 FDC-6-2 1 and 2 500, 1000, Max

11 FDC-6-3 1, 2, and 3 750, 1200, Max

* Test ID nomenclature used in this test program follows the format: XXX-X-Y, where “XXX-X” is FDC ID and “-Y” represents the number of charged inlet(s).

41 Water flow at 750 gpm through a 2.5-inch diameter conduit will result in a flow velocity of approximately 49

ft/s.

January 8, 2016

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4 FDC Descriptions

In conjunction with FPRF, Exponent procured a total of six (6) FDCs for testing. A description

of each FDC procured is provided in Table 2, below.

Table 2 FDC Descriptions

FDC ID FDC Type Description Figure Manufacturer

FDC-1 Single

Flush single inlet

Material: Brass

Size: 2.5-in x 2.5-in

Figure 3 A

FDC-2 Single

Flush single inlet

Material: Brass

Size: 2.5-in x 2.5-in

Figure 4 B

FDC-3 Single

Flush single inlet

Material: Brass

Size: 2.5-in x 2.5-in

Figure 5 C

FDC-4 Siamese

Freestanding siamese with single clapper two-way inlet

Material: Brass

Size: 4-in x 2.5-in x 2.5-in

Figure 6

Figure 7 B

FDC-5 Siamese

Projecting siamese with double clappers two-way inlets

Material: Brass

Size: 4-in x 2.5-in x 2.5-in

Figure 8

Figure 9 D

FDC-6 Triamese

Flush triamese with triple clappers three-way inlets

Material: Brass

Size: 6-in x 2.5-in x2.5-in x 2.5-in

Figure 10 B

4.1 Single FDCs

Three (3) single FDCs (FDC-1, FDC-2, and FDC-3) from three different manufacturers were

procured for testing. All three FDCs procured were flush type with a 2.5-inch American

National Fire Hose Screw Threads (NH) swivel female inlet and a 2.5-inch National Pipe

Thread (NPT) female outlet. The appearances and dimensions of all three single FDCs were

very similar, but FDC-1 was slightly longer, while FDC-2 and FDC-3 were almost identical.

All three single FDCs were equipped with rubber gaskets on the inlet side, although there were

January 8, 2016

1505254.000 7849 17

slight variations in gasket thickness and width among the three single FDCs. A comparison of

the single FDCs is provided in Figure 2. None of the single FDCs were equipped with clappers.

4.2 Siamese FDCs

Two (2) siamese FDCs (FDC-4 and FDC-5) from different manufacturers were obtained for

testing. Both siamese FDCs contained two (2) 2.5-inch NH swivel female inlets equipped with

rubber gaskets and a 4-inch NPT female outlet. FDC-4 was a freestanding type (integral 90°

orientation) with a single inlet clapper, as shown in Figure 6 and Figure 7. FDC-5 was a

projecting type with dual inlet clappers, as shown in Figure 8 and Figure 9. The clappers in

both siamese FDCs (FDC-4 and FDC-5) were not equipped with a spring-loaded closing

mechanism (snoot type clappers).

4.3 Triamese FDC

One triamese FDC (FDC-6) was procured for testing, as shown in Figure 10 and Figure 11. The

triamese FDC was a flush wall-mount type with three (3) 2.5-inch female NPT inlets with triple

inlet clappers and a 6-inch NPT female outlet. No rubber gasket was provided with the triamese

FDC and the clappers were not equipped with a spring-loaded closing mechanism.

Figure 2 Single FDCs

FDC-1 FDC-2 FDC-3

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Figure 3 Single flush FDC (FDC-1)

Figure 4 Single flush FDC (FDC-2)

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Figure 5 Single flush FDC (FDC-3)

Figure 6 Siamese freestanding FDC (FDC-4)

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Figure 7 Siamese freestanding FDC (FDC-4); view from bottom showing single clapper

Figure 8 Siamese projecting FDC (FDC-5)

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Figure 9 Siamese projecting FDC (FDC-5); view through outlet showing double inlet clappers

Figure 10 Triamese flush FDC (FDC-6)

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Figure 11 Triamese flush FDC (FDC-6); view through inlet showing clappers

January 8, 2016

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5 Test Setup

The FDC flow testing was performed at MFRI in College Park, Maryland.42 The overall intent

of the testing was to provide a repeatable scientific experiment that characterizes the flow

characteristics at the maximum actual flow rate for each 2.5-inch FDC inlet. The data generated

was then used to support the current 250 gpm requirement or recommend a change to the

standard. The following are key assumptions related to the testing:

The FDCs procured for this test program are only a small set of samples intended to

provide a preliminary understanding of FDC hydraulic characteristics (i.e., flow rate and

pressure loss). The test results from this study are not representative of all available

FDCs of similar types.

FDC flow rate data obtained from this test program is specific to the upstream supply

line configuration and components used in this test program (i.e., hoses and fittings).

These upstream supply components are commonly used during fire department

operations and their friction loss characteristics are well documented.

A series of flow tests were conducted on common FDCs with the following objectives: 1) to

determine the maximum flow rate that can be achieved for each 2.5 inch inlet and 2) to measure

the pressure losses associated with each type of FDC as a function of the flow rate. Data

collected during these tests included:

Total FDC discharge flow rates;

Pressure losses;

Test observations;

Still photography; and

High definition video.

42 MFRI provides a world class test facility for research, development, and testing of fire protection systems and

fire service technologies in live-fire conditions.

January 8, 2016

1505254.000 7849 24

MFRI provided the facility for the flow tests, the fire department apparatus and water supply,

and qualified personnel to conduct the actual water flow.

Exponent performed the following tasks:

Test observations and data monitoring;

Providing and installing the flow rate and pressure measurement devices and data

acquisition system (DAQ);

Still photography; and

High definition video recording;

5.1 Test Apparatus

The test apparatus setup is described herein as follows.

5.1.1 Water Flow Activities

Water flow activities were handled by MFRI. All tests were conducted by three active duty

firefighters utilizing a fire department pumper43, Model 2011 Pierce Arrow XT, rated at 2,000

gpm capacity and capable of charging water through up to six (6) 2.5-inch hose lines with a

minimum net pressure of 150 psi per NFPA 1901, Standard for Automotive Fire Apparatus.

The fire department pumper used in this test program is shown in Figure 12.

The test apparatus utilized water from a municipal hydrant producing a static pressure of 100 psi

and a residual pressure of 50 psi at a 3,757 gpm flow rate.44 Water was discharged into a

collection funnel, allowing the water to flow into a drafting basin with its drainage open during

testing (see Figure 13 and Figure 14).

43 Engine 122, College Park Volunteer Fire Department, Maryland. 44 Hydrant Test – Hydrant 62, dated 6/1/2013

January 8, 2016

1505254.000 7849 25

Figure 12 Fire department pumper apparatus

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Figure 13 Test facility and drafting basin at MFRI

Figure 14 Test platform with single FDC and test apparatus secured to test platform

January 8, 2016

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Figure 15 Test platform with siamese FDC and test apparatus secured to test platform

Figure 16 Test platform with triamese FDC and test apparatus secured to test platform

January 8, 2016

1505254.000 7849 28

5.1.2 Supply Hose Line

In all flow tests, 2.5-inch diameter double-jacket rubber-lined standard fire hoses with a total

length of 100 feet (two 50-foot length sections) were used to supply water to the FDC inlets.

The use of a 2.5-inch diameter hose eliminated the need for any hose adapters before connecting

to the FDC inlets and the 100-foot length was required given the location of the fire department

pumper and the test apparatus during the test.

While the total flow rate obtained from this test program is specific to the selected hose size and

configuration, the pressure loss for each FDC is a function of the flow rate and is independent of

the hose configuration or pressure losses from the upstream components. Pressure losses for

fire hoses with different lengths and diameters are well characterized and documented.45

5.1.3 Flow Test Assembly

During each flow test, the FDC assembly was secured to the test platform to allow for safely

discharging water into the drafting basin. A pressure transducer was instrumented upstream of

each FDC inlet. Downstream of the FDC outlet, an in-line averaging pitot tube was

instrumented to obtain the total flow rate, as well as the pressure drop across the FDC. The

inlets and outlet of the FDC were connected with steel pipes with appropriate lengths to allow

for accurate pressure measurements at approximately five times the pipe diameter (5D) length

upstream and up to ten times the pipe diameter (10D) length downstream of the FDC. With the

exception of pressure readings on the supply hoses from the fire department pumper and the

differential pressure on the in-line averaging pitot tube, all pressure measurements were

recorded via a data acquisition system to allow for real-time monitoring of the flow condition to

ensure pressure data during the steady state flow conditions were captured at a target flow rate.

Calibrated pressure transducers (Omega PX309) were used for the pressure measurements in

this test program. Figure 17 through Figure 19 provide the schematics for the flow test

assembly.

45 Scheffey, J.L., et al., Determination of Fire Hose Friction Loss Characteristics, The Fire Protection Research

Foundation, October 2013.

January 8, 2016

1505254.000 7849

29

Figure 17 Flow test schematic for single FDC

Figure 18 Flow test schematic for siamese FDC

Supply from Street

Hydrant

Single FDC

PU1,n

In-line Pitot

Manometer for Flow Rate Measurement

PD, t

Pressure Transducer

Pumper

Pp1

Discharge to Drafting

Basin 2.5” Hose Line 100 ft 1 ft (~5D)

2.5” Steel Pipe 2 ft (~10D)

2.5” Steel Pipe

NTS

Supply from Street

Hydrant

Siamese FDC

PU1, n

In-line Pitot

PD, t

Pressure Transducer

Pumper

Pp1

Discharge to Drafting

Basin

2.5” Hose Line

2.5” Steel Pipes 3 ft (~10D)

4” Steel Pipe

PU2, n

2.5” Hose Line

100 ft

Pp2

1 ft (~5D)

NTS

Manometer for Flow Rate Measurement

January 8, 2016

1505254.000 7849

30

Figure 19 Flow test schematic for triamese FDC

Supply from Street

Hydrant

Triamese FDC PU1, n

In-line Pitot

PD, t

Pressure Transducer

Pumper

Pp1

Discharge to Drafting

Basin

2.5” Hose Line

2.5” Steel Pipes

3 ft (~6D)6” Steel Pipe

PU2, n

2.5” Hose Line

100 ftPp2

1 ft (~5D)

PU3, n

Pp3

NTS

Manometer for Flow Rate Measurement

January 8, 2016

1505254.000 7849 31

5.1.4 Flow Rate Measurements

During the flow testing, the FDC flow rate was determined based on the measurements of the

differential pressure between the total pressure (stagnation pressure) and the normal pressure

using an in-line averaging pitot tube instrumented downstream of the FDC. Three different

models of in-line averaging pitot tubes (Dwyer DS-300-2-1/2, DS-300-4, and D-S400-6) were

used depending upon the type and outlet size of the FDC. A schematic for the in-line pitot tube

is shown in Figure 20.

Figure 20 Flow rate measurement with in-line averaging pitot tube

A calibrated digital manometer (Dwyer 477-7-FM) was used to measure the differential

pressures at the in-line pitot tube, which were then used to calculate the total discharge flow rate

based on the following expression46:

46 Dwyer Instruments, Inc. DS Flow Sensors – Installation and Operating Instructions Flow Calculations, FR72-

440451-01 Rev. 2, July 2004

Flow Direction

Connecting to digital manometer and

pressure transducer

Connecting to digital manometer

January 8, 2016

1505254.000 7849 32

5.668 ∙ ∆ / (1)

where Q is the flow rate expressed in gpm; K is the flow coefficient (0.62 for a 2.5-inch pipe,

0.67 for a 4-inch pipe, and 0.71 for a 6-inch pipe); D is the inside pipe diameter in inches; P is

the differential pressure in inches-of-water-column; and Sf is specific gravity of water at the

flowing condition.47

5.1.5 Pressure Loss Measurements

In general, pressure losses through the FDC can be theoretically estimated based on the

difference between the total pressures measured upstream and downstream of a hydraulic

component when the change in elevation is negligible. The total pressure (Pt) is given as a sum

of the normal pressure (Pn) and the velocity pressure (Pv):

(2)

The normal pressure is the pressure acting against, or perpendicular to the hydraulic component

wall. The velocity pressure is a measure of the energy required to keep the water in motion.

The velocity pressure always acts in the direction of water flow, while the normal pressure acts

perpendicular to the velocity pressure.48

For this test program, the pressure loss associated with each FDC was determined based on the

difference between the total pressure obtained from upstream and downstream of the FDC and

the pressure losses associated with the steel pipes upstream and downstream of the FDC. The

downstream total pressure was directly measured using the in-line averaging pitot tube, whereas

the upstream total pressure was estimated from the summation of the measured upstream

normal pressure and the calculated velocity pressure, which is given as49:

0.001123 / (3)

47 At the time of the test, water temperature was approximately 60°F corresponding to the specific gravity of 1. 48 NFPA, Automatic Sprinkler Systems Handbook, 10th Edition, p. 800 49 NFPA 13-2013, Section 23.4.2.2

January 8, 2016

1505254.000 7849 33

where Q is inlet flow rate in gpm and D is the inside pipe diameter in inches. For single FDCs,

the inlet flow rate is equal to the measured discharge flow rate. For the siamese and triamese

FDCs, the inlet flow rate is determined based on the assumption that the inlet flows are equally

divided and conservation of mass applies (i.e., the sum of the inlet flows equals the discharge

flow).

5.1.6 DAQ System

With the exception of pressure readings on the supply hoses from the fire department pumper

and the differential pressure on the in-line averaging pitot tube, all pressure measurements were

recorded via a Fluke 2638A Hydra Series III DAQ system to allow for real-time monitoring of

the pressures and flow conditions at one second intervals (1 Hz). The DAQ system was used to

capture the pressure data during steady state flow conditions, as well as to post process the

pressure data to minimize the potential effect of vibration and other measurement noise during

the flow testing.

5.1.7 Still Photography and High Definition Video

Still photography and high definition video were recorded during the flow testing. Still

photography was captured using a Nikon D3300 digital camera and high definition video was

captured using multiple Canon Vixia high definition camcorders.

5.2 Flow Test Protocols

The operation of the fire department apparatus and water flow activities were conducted by

MFRI and qualified personnel (i.e., active duty firefighters) in accordance with NFPA 13E.

Exponent instrumented the measurement devices, recorded observations, and monitored the data

collected during testing.

The test preparation protocol was as follows:

1. Connect the FDC inlet(s) and outlet to the upstream and downstream steel pipe sections

that were pre-instrumented with appropriate pressure transducers and an in-line pitot

tube.

January 8, 2016

1505254.000 7849 34

2. Secure the FDC and test apparatus to the test platform.

3. Connect the 2.5-inch supply hose lines to the inlet steel pipe sections and to the fire

department pumper.

4. Straighten the supply hose line as much as possible to minimize the pressure loss.

5. Ensure the drainage to the drafting basin and the general test assembly are in proper

operating condition.

6. Initialize and ensure proper operation of the fire department pumper (conducted by

MFRI) in accordance with NFPA 1901, NFPA 13E, and SOPs, as approved by MFRI

and the qualified operator(s).

The test protocol was as follows:

1. Start the DAQ system and allow for background data to be collected for a minimum of 1

minute.

2. Start high definition video recording simultaneously with data collection.

3. Charge water to the FDC inlet(s) with low flow condition (no greater than 150 gpm) and

ensure no or minimal leaks on the test assembly and proper discharge of water to the

drafting basin.

4. Monitor the flow rate on DAQ system and gradually increase the flow to the target flow

rates as outlined in the test matrix.

5. Record the pressure readings at the pumper for the upstream supply hose.

6. When the target flow rate is reached, allow a minimum of 2 minutes for steady state flow

conditions to develop.

7. Repeat Steps 4 and 5 to collect data at the next target flow rate.

8. After the maximum flow is reached and the data collected, gradually decrease to a lower

target flow rate and repeat the measurements.

9. Still photographs were recorded throughout the test as necessary.

10. After the completion of all data collection for all target flow rates, stop the fire

department pumper, and turn of all data collection equipment.

January 8, 2016

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6 Test Results

The following section is a presentation of the data collected during the flow tests along with a

brief discussion of the data processing to determine the flow rate achieved during the test and

ultimately the pressure losses associated with the FDCs.

The FDC flow testing was performed at the MFRI facility located at 4500 Paint Brach Parkway,

College Park, Maryland 20742 on October 26, 2015. A total of eleven (11) tests were

conducted; three (3) tests using three single FDCs (FDC-1 through FDC-3), four (4) tests using

two siamese FDCs (FDC-4 and FDC-5), and four (4) tests using one triamese FDCs (FDC-6).

Figure 21 through Figure 23 provide representative views of the flow testing for each FDC type.

As shown in Figure 24, the differential pressures were measured using a digital manometer at

the in-line pitot tube. Using Eq. (1) the differential pressures were then used to calculate the

total discharge flow rates presented in Table 3.

The pressure measurements in this test program included the total pressure measured

downstream of the discharge pipe ( , ) and the normal pressure(s) measured upstream of the

respective inlet pipe(s) ( , , , and , ). At their respective flow rates, the pressures

were recorded for a minimum of two minutes to ensure that steady state flow conditions were

established. The average pressure data over the steady state period are reported in Table 3.

Additionally, detailed pressure data recorded at the pumper for each test is provided in

Appendix A, for reference. The pressure losses associated with the FDCs were determined

directly based on the pressure measurement downstream of the hose lines, as discussed in this

section, independently from the pumper pressure data.

January 8, 2016

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Figure 21 Single FDC flow test

Figure 22 Siamese FDC flow test

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Figure 23 Triamese FDC flow test

Figure 24 Measurement layout

From Pumper

NTS

FDC

PU1, n

In-line Pitot

Manometer for Flow Rate Measurement

PD, t

Pressure Transducer

Discharge 2.5” Hose Inlet pipe Discharge pipe

Discharge pipe pressure loss

∆ , )

Inlet pipe pressure loss

∆ , )

FDC Pressure Loss

(∆ )

January 8, 2016

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Table 3 Test Measurement Results

Test ID FDC Type

Flow to

Inlet(s)

Manometer [inch-H2O]

Total Discharge Flow [gpm]

Average Pressure [psi]50 FDC Pressure Loss [psi] PD,t PU1,n PU2,n PU3,n

FDC‐1‐1 

Single 1 

160  271  3.4  2.0  ‐  ‐  0.2 

551  503  12.2  7.6  ‐  ‐  1.2 

1047  693  23.6  14.0  ‐  ‐  1.3 

FDC‐2‐1 

Single 1 

172  281  3.7  2.0  ‐  ‐  0.0 

495  478  10.3  5.7  ‐  ‐  0.6 

503  481  11.0  6.1  ‐  ‐  0.4 

926  652  24.7  15.6  ‐  ‐  0.6 

FDC‐3‐1 

Single 1 

118  233  3.5  2.3  ‐  ‐  0.0 

551  503  11.4  6.6  ‐  ‐  0.9 

962  664  20.7  13.9  ‐  ‐  3.3 

1167  732  26.4  17.6  ‐  ‐  3.5 

FDC‐4‐1 

Siamese 1 

53  448  1.2  1.1  ‐  ‐  5.5 

101  642  2.4  8.5  ‐  ‐  14.6 

109  618  2.7  5.8  ‐  ‐  16.7 

153  761  3.2  12.0  ‐  ‐  24.9 

FDC‐4‐2 

Siamese 2 

216  906  5.8  8.5  8.3  ‐  8.1 

304  1073  7.7  9.3  10.5  ‐  9.2 

401  1232  10.1  12.5  14.2  ‐  12.5 

478  1345  11.9  17.5  16.3  ‐  17.5 

588  1492  13.7  19.3  19.1  ‐  20.3 

FDC‐5‐1 

Siamese 1 

80  552  1.4  1.3  ‐  ‐  8.3 

129  700  3.1  6.5  ‐  ‐  17.1 

159  777  4.1  8.2  ‐  ‐  20.9 

FDC‐5‐2 

Siamese 2 

198  865  5.1  8.6  8.1*  ‐  8.4 

255  982  6.9  19.4  19.7*  ‐  18.8 

445  1298  10.5  22.2  23.8*  ‐  22.8 

551  1445  12.8  27.8  24.4*  ‐  28.9 

FDC‐6‐1A 

Triamese 1 

14  554  0.28  7.4  ‐  ‐  15.8 

15  566  0.35  11.4  ‐  ‐  20.1 

FDC‐6‐1B 

Triamese 1 

44  979  0.9  10.6  ‐  ‐  36.9 

46  1006  0.9  10.4  ‐  ‐  38.3 

53  1076  1.8  5.9  ‐  ‐  36.9 

FDC‐6‐2 

Triamese 2 

47  1012  1.1  2.3  0.2*  ‐  8.4 

63  1171  1.2  6.0  2.0*  ‐  14.4 

98  1467  1.8  10.4  10.4*  ‐  23.7 

135  1717  2.6  16.8  13.8*  ‐  35.0 

FDC‐6‐3 

Triamese 3 

92  1420  2.3  7.5  5.1  7.4*  11.5 

98  1462  1.9  5.6  5.6  4.5*  10.4 

139  1748  3.5  12.6  9.2  8.3*  18.6 

141  1755  3.5  10.7  9.2  9.1*  16.7 

151  1818  3.7  12.4  9.6  8.1*  18.9 

50 Note (*) Supplemental technique is used to determine certain upstream pressure due to cavitation created by hose orientations

during testing.

January 8, 2016

1505254.000 7849 39

The maximum flow for each test was based on the available flow capacity at the hydrant and

additional safety considerations. For this test program, the maximum flows were measured at

732 gpm for single FDCs. For the siamese and the triamese FDCs, the maximum flow rates

achieved were 1,492 gpm and 1,818 gpm, respectively, when all inlets were simultaneously

charged.

As presented in Table 3, the normal pressure(s) measured upstream of the inlet pipe(s) ( , ,

, ,and , ) for siamese and triamese FDCs are relatively similar at their respective flow

rates, with a variation of up to ±3 psi. This observation is supportive of the fact that the inlet

flows to the siamese and triamese FDCs are equally split. As such, only , was used to

further calculate the upstream normal pressure ( , ) based on Eq. (3) as follows:

, , 0.001123 / (4)

where is inlet flow (gpm), and is inside diameter of the inlet pipe (in). In addition, the

pressure loss associated with the FDC is given as:

∆ , ∆ , , ∆ , (5)

where ∆ , and ∆ , are the pressure losses associated with the inlet and outlet pipes

respectively. The pressure loss attributed to the fully developed, steady state, incompressible

flow through a pipe section is estimated based on the Darcy-Weisbach equation as follows:

∆ 0.000216 / , (6)

where is friction loss factor as provided by a Moody diagram, is length of pipe (ft), is water

density (lb/ft3), is flow in pipe (gpm), and is inside diameter of pipe (in). Following Eq. (4),

(5), and (6), the pressure losses that occur between the inlet and the outlet of the FDCs at a

given flow rate are estimated and summarized in the last column of Table 3.

January 8, 2016

1505254.000 7849 40

7 Analysis and Discussion

The following section is a discussion of the data and observations collected during the flow tests

and serves to supplement the presentation of the data in Section 6.

7.1 Single FDC

A total of three single FDCs (FDC-1, FDC-2, and FDC-3) were tested and their pressure losses

as a function of flow rates are presented in Figure 25. The error bars represent a single standard

deviation for the data collected during the steady state flow condition. Also included in Figure

25 are solid lines representing a fitted trend line for the pressure losses as a function of flow rate

based on the following expression:

∆ / , (7)

where is the average pressure loss coefficient for the FDC, is the total discharge flow,

and is the inside diameter of the FDC discharge outlet.

Figure 25 Single FDC pressure loss data

0

1

2

3

4

5

6

0 200 400 600 800

Pressure Loss [psi]

Flow Rate [gpm]

FDC‐1‐1

FDC‐2‐1

FDC‐3‐1

CFDC = 0.0041

CFDC = 0.0032

CFDC = 0.0014

January 8, 2016

1505254.000 7849 41

Based on the test results, the maximum flow rate for the single FDCs during testing was

approximately 730 gpm, 2.8 times the prescriptive requirement of 250 gpm per inlet provided in

NFPA 14. In addition, it is possible that a higher flow rate could have been achieved during the

single FDC testing given the capacity of the water supply and the pumper. However, a limit for

flow of no greater than 750 gpm per inlet was selected due to a safety consideration based on a

high velocity flow (approximately 49 ft/s).

Based on the test results, FDC-2 produced the lowest pressure losses, while FDC-3 provided the

greatest pressure loss among the three single FDCs. While slight differences in the pressure

losses were observed among the three single FDCs, especially at a higher flow rates, the

variation was small (within ±2 psi). The rubber gaskets used in each manufacturer’s FDC are

slightly different in size and thickness, which could account for the variation observed at higher

flow rates.

For the range of the tested flow rates, the pressure losses associated with all tested single FDCs

were generally small. While the error bars suggest a greater variability of the data taken at a

higher flow rate, the maximum pressure loss is expected to be low even at values approximately

three times that of the prescriptive flow rate.

7.2 Siamese FDC

Two siamese FDCs (FDC-4 and FDC-5) were tested, each with only one inlet charged and with

both inlets simultaneously charged. The pressure losses are presented in Figure 26. The error

bars represent a single standard deviation for the data collected during the steady state flow

condition. Also included in Figure 26 are solid lines representing a fitted trend line for the

pressure losses as a function of flow rate based on Eq. (7).

The total flow rate data provided in Figure 26 is the total discharge flow rate measured within

the discharge pipe. Based on the test results, the maximum flow that was achieved during

testing was 777 gpm when only one inlet was charged with water and 1,492 gpm when both

inlets were charged. Similar to the single FDC flow testing, the flow tests for the siamese FDCs

were concluded at the selected maximum flows based on safety considerations.

January 8, 2016

1505254.000 7849 42

As observed in this test program, the greatest pressure loss associated with the siamese FDC

was approximately 25 psi when only one inlet was charged at 761 gpm and 29 psi when both

inlets were charged with a total flow of 1,445 gpm. In general, at a respective total discharge

flow rate, the pressure losses associated with the siamese FDC is optimized (i.e., minimized)

when both inlets are charged.

Figure 26 Siamese FDC pressure loss data

Models of siamese FDCs with varying clapper designs were included in the testing. FDC-4 was

a freestanding type (integral 90° orientation) FDC with a single inlet clapper and FDC-5 was a

wall-mount type FDC with dual inlet clappers (see Figure 6 through Figure 9). When only one

inlet was charged (FDC-4-1 and FDC-5-1 tests), both FDC-4 and FDC-5 produced similar

pressure loss characteristics, with FDC-4 producing slightly higher pressure loss values at a

given flow rate. When both inlets were simultaneously charged (FDC-4-2 and FDC-5-2 tests),

FDC-4 hydraulically performed better, with lower pressure losses compared to FDC-5. Based

on these test results, the presence of an internal clapper can influence the pressure loss

characteristics of the FDC.51 The results also indicated that when only one inlet was charged,

there was no noticeable difference in the pressure losses experienced between FDCs with one or

51 The orientation of the freestanding siamese FDC (FDC-4) during testing may have had some impact on clapper

behavior, but such impact is expected to be minimal.

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200 1400 1600

Pressure Loss [psi]

Total Flow Rate [gpm]

FDC‐4‐1

FDC‐4‐2

FDC‐5‐1

FDC‐5‐2CFDC = 0.0341

CFDC = 0.0397

CFDC = 0.0095

CFDC = 0.0154

January 8, 2016

1505254.000 7849 43

two inlet clappers. The difference in pressure loss was noticeable in the two-clapper model

when both inlets were charged, as both clappers likely interfered with the flow, creating higher

pressure losses. None of the clappers in the FDCs tested utilized a spring-loaded closing

mechanism.

Further, the results also suggest that the difference in the geometry and shape of FDC-4 and

FDC-5 (i.e., freestanding versus projecting) is less influential to the pressure loss performance

than the presence of the clappers. The geometry of the freestanding model is expected to

inherently contain a greater flow restriction compared to that of the projecting model (i.e., a

convergence plus a sharp, 90° turn versus a convergence alone). However, the fact that the

freestanding model with one clapper (FDC-4) showed better hydraulic performance than the

projecting model with two clappers (FDC-5) indicates that the clappers have a greater impact to

the pressure losses than the geometry of the FDC.52

7.3 Triamese FDC

One triamese FDC (FDC-6) equipped with non-spring-loaded inlet clappers was tested and the

pressure loss data is presented in Figure 27 below, along with error bars for the standard

deviation and the trend lines following Eq. (7). Four separate tests were performed on the

triamese FDC, including two tests with only one inlet charged (FDC-6-1A and FDC-6-1B); one

test with two inlets charged (FDC-6-2) and one test with all three inlets charged (FDC-6-3).

52 This observation is specific to the FDCs tested and may not be universally applicable to all FDCs.

January 8, 2016

1505254.000 7849 44

Figure 27 Triamese FDC pressure loss data

Based on the test results, the maximum flow rate that was achieved was 1,076 gpm when only

one inlet was charged (FDC-6-1B), with the corresponding pressure loss at approximately 40

psi. A maximum flow rate of 1,717 gpm was achieved when two inlets were charged (FDC-6-

2) with a corresponding pressure loss of 35 psi and a maximum flow rate of 1,818 gpm was

achieved when all three inlets were charged (FDC-6-3) with a corresponding pressure loss of 19

psi. For tests FDC-6-2 and FDC-6-3, the tests concluded with their maximum flow rate when

the water supply reached its maximum capacity, i.e. when the hydrant residual pressure reduced

below 20 psi.53 In general, at a respective total discharge flow rate, the pressure loss associated

with the triamese FDC reduced with more inlets connected, similar to the observations made for

the siamese FDCs.

7.4 FDCs Pressure Loss Characteristics

The pressure loss associated with water flow through FDCs can be expressed as a direct

function of a squared flow rate, , a characteristic length (i.e., pipe diameter) to the fifth

power, , and a pressure loss coefficient, , as previously shown in Eq. (7), which follows

53 NFPA, Fire Protection Handbook, 20th Edition, Section 15, Chapter 2, p. 15-24.

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200 1400 1600 1800 2000

Pressure Loss [psi]

Total Flow Rate [psi]

FDC‐6‐1A

FDC‐6‐1B

FDC‐6‐2

FDC‐6‐3

CFDC = 0.0815

CFDC = 0.0456

CFDC = 0.3496

January 8, 2016

1505254.000 7849 45

the form of the Darcy-Weisbach equation. In general, the pressure loss coefficient is strongly

dependent on the geometry of the component considered and the greater the coefficient, the

greater the pressure loss.54 The FDC pressure loss coefficient, , based on the test results

from this test program are as provided in Table 4.

Table 4 FDC Pressure Loss Coefficients

FDC ID Test ID Flow to Inlets FDC Pressure Loss Coef.

( )

FDC-1 FDC-1-1 1 0.00032

FDC-2 FDC-2-1 1 0.00014

FDC-3 FDC-3-1 1 0.00041

FDC-4 FDC-4-1

FDC-4-2

1

2

0.0396

0.0095

FDC-5 FDC-5-1

FDC-5-2

1

2

0.0341

0.0154

FDC-6

FDC-6-1 (A&B)

FDC-6-2

FDC-6-3

1

2

3

0.3496

0.0815

0.0456

Given that the pressure losses obtained from this test program track reasonably well with the

pressure loss expression in Eq. (7), using the FDC pressure loss coefficient, extrapolated data

based on the pressure loss coefficients for all tested FDCs are presented in Figure 28.

54 Munson et al, Fundamentals of Fluid Mechanics, 5th Edition, 2006, p.437

January 8, 2016

1505254.000 7849 46

Figure 28 FDC pressure loss characteristics

The pressure losses across single FDCs are the lowest in comparison to that of siamese and

triamese FDCs. This observation is consistent with the geometry of the single FDCs that is

typically smooth, clapper-less, and contains very little resistance in comparison to that of the

siamese or the triamese FDCs, where inherent flow restrictions including turns, bends, and

clappers are incorporated as part of their designs.

Based on the pressure loss characteristics of the FDCs obtained in this study, when only one

inlet is charged with a flow rate of 500 gpm, two times that of the current NFPA 14

requirement, a resultant pressure loss of approximately 10 psi or less is expected. This level of

pressure loss is equivalent to a pipe pressure loss created by flowing 500 gpm of water through

an approximately 14-foot length of 2.5-inch schedule (SCH) 40 steel pipe.55 In addition, when

multiple inlets are charged with a flow rate of 500 gpm per inlet, substantial flow rates can be

achieved for siamese and triamese FDCs, while the pressure loss across the FDC is only 55 Based on the Darcy-Weisbach formula for friction loss

0

5

10

15

20

25

30

35

40

45

0 200 400 600 800 1000 1200 1400 1600 1800 2000

Pressure Loss [psi]

Total Flow Rate [gpm]

FDC-3-1 CFDC = 0.0041

FDC-1-1 CFDC = 0.0032

FDC-2-1 CFDC = 0.0014

FDC-6-3 CFDC = 0.0456

FDC-6-2 CFDC = 0.0815

FDC-6-1 CFDC = 0.3496

FDC-4-2 CFDC = 0.0095

FDC-4-1 CFDC = 0.0397

FDC-5-2 CFDC = 0.0154

FDC-5-1 CFDC = 0.0341

250 gpm

NFPA 14 500 gpm

January 8, 2016

1505254.000 7849 47

expected to increase to approximately 15 psi, which is equivalent to flowing 500 gpm through a

21-foot length of 2.5-inch SCH 40 steel pipe.

For a flow rate of 800 gpm per inlet, approximately 3.2 times that of the current NFPA 14

requirement, the pressure loss associated with the FDC is expected to be up to 27 psi when one

inlet is charged and 37 psi when multiple inlets are simultaneously charged. This level of

pressure loss can have a potential impact to the hydraulic performance of the automatic fire

suppression and/or standpipe when relying on the FDC for the water supply.

7.5 Section Summary

Three single FDCs were tested at a maximum flow rate of approximately 730 gpm and resulted

in a corresponding pressure loss of less than 5 psi. Two siamese FDCs were tested at a

maximum flow rate of 777 gpm with one inlet charged and 1,492 gpm with both inlets charged

and resulted in a corresponding pressure loss of less than 30 psi for both configurations. One

triamese FDC was tested at a maximum flow rate of 1,076 gpm with one inlet charged, 1,717

gpm with two inlets charged, and 1,818 gpm with all three inlets charged and resulted in

corresponding pressure losses of 40 psi, 35 psi, and 19 psi, respectively. The tested siamese and

triamese FDCs were provided with clappers, but none were equipped with a spring-loaded

closing mechanism.

The pressure losses across single FDCs were the lowest in comparison to that of siamese and

triamese FDCs.

For a flow rate of 250 gpm per inlet, the pressure loss associated with the FDC was found to be

insignificant (i.e., less than 5 psi). At a flow rate of 500 gpm per inlet (two times current NFPA

14 requirement), the pressure loss was found to be up to approximately 10 psi when only one

inlet was charged and up to 15 psi when multiple inlets were each flowing 500 gpm (i.e. a total

of 1,000 gpm for the siamese and a total of 1500 gpm for the triamese). At a flow rate of 800

gpm per inlet (3.2 times the current NFPA 14 requirement), the pressure loss up to 27 psi when

one inlet was charged and up to 37 psi when multiple inlets were each flowing 800 gpm,

potentially impacting the hydraulic performance of the systems.

January 8, 2016

1505254.000 7849 48

8 Key Findings

Based on the literature review and the full-scale FDC flow testing conducted in this test

program, the key findings are presented as follows.

NFPA 14 currently requires that the full standpipe system demand be available from FDCs and

requires one (1) 2.5-inch diameter inlet for every 250 gpm of standpipe demand. The majority

of surveyed municipalities adopt NFPA 14 with no modification of the default NFPA 14 FDC

inlet flow requirements. Municipalities that deviate from the NFPA 14 requirements generally

use the number of exposures and length of the building exposure side to determine the number

of FDCs required. In addition, NFPA 14 requires manual standpipe systems be designed to

provide 100 psi at the topmost outlet, with hydraulic calculations terminating at the FDC,

however, pressure loss characteristic for the FDC itself are not provided in the standard, and

data from the manufacturers is currently unavailable. The lack of the scientific basis for the

required flow rate and the unavailability for the FDC pressure loss information are the main

driving forces of this study.

FDC full-scale flow testing indicates that a flow rate of approximately 730 gpm, nearly three

times that of the prescriptive requirement in the current edition of NFPA 14, can be achieved

through a single FDC with a 2.5-inch inlet with a pressure loss of less than 5 psi. For siamese

and triamese FDCs, flowing through one 2.5-inch inlet with a comparable flow rate yields a

pressure loss up to approximately 25 psi, five times that of the single FDC. When more than

one 2.5-inch inlet is charged with water simultaneously, a greater flow rate can be achieved with

a lower pressure loss through the FDCs. For siamese FDCs, the maximum flow rate achieved

was 1,492 gpm when both inlets were charged, which resulted in a pressure loss of less than 30

psi. For the triamese FDC, the maximum flow rate achieved was 1,818 gpm when all three

inlets were charged, which resulted in a pressure loss of 19 psi pressure loss.

January 8, 2016

1505254.000 7849 49

Based on the pressure loss characteristics of the FDCs obtained in this study, the following

conclusions are made:

For a flow rate of 250 gpm per 2.5-inch diameter inlet (current NFPA 14 requirement),

the pressure loss associated with the FDC is insignificant (i.e., less than 5 psi).

For a flow rate of 500 gpm per 2.5-inch diameter inlet (two times the NFPA 14

requirement), the FDC pressure loss is expected to be up to 10 psi when one inlet is

charged and up to 15 psi when multiple inlets are each flowing 500 gpm.

For a flow rate of 800 gpm per 2.5-inch diameter inlet (3.2 times the NFPA 14

requirement), the FDC pressure loss is expected to be up to 27 psi when one inlet is

charged and up to 37 psi when multiple inlets are each flowing 800 gpm, potentially

creating an impact on system hydraulic performance.

The current NFPA 14 prescriptive requirement of 250 gpm per 2.5-inch diameter inlet is

very conservative, and a flow rate of 500 gpm per 2.5-inch diameter inlet is expected to

have a minimal impact on the hydraulic performance of the system.

If the current flow per FDC inlet is increased so as to allow for reduction in the required

number of FDC inlets for standpipe systems, consideration for the total number of FDC

inlets, each capable of supplying the hydraulic demand, should be given to structures

where redundancy in FDC locations and/or access may be critical. The allowable

number of inlets should also be subject to approval by the local authorities due to site

and access specific conditions.

January 8, 2016

1505254.000 7849 50

9 Acknowledgements

The authors would like to thank the MFRI crews for their significant efforts in setting up,

instrumenting, and conducting the full-scale flow tests.

The authors further thank:

Casey Grant, Research Director of the FPRF

Kathleen Almand, Executive Director of the FPRF

Amanda Kimball, Research Project Manager of the FPRF

Peter Schwab, Wayne Automatic Fire Sprinklers Inc.

Jim Widmer, Morris Group International, Potter Roemer

College Park Volunteer Fire Department

The Project Technical Panel

We would also like to thank a number of our colleagues at Exponent who provided assistance,

input, and advice.

January 8, 2016

1505254.000 7849

51

Appendix A

Table 5 Pressure Data

Test ID FDC Type

Flow to Inlet(s)

Total Discharge

Flow [gpm]

Pumper Pressure Data [psi] Average Pressure [psi] (b) FDC

Pressure Loss [psi]

Intake Pressure

Set Pressure (a)

Pump Pressure

Discharge Pressure

Pp1

Discharge Pressure

Pp2

Discharge Pressure

Pp3 PD,t PU1,n PU2,n PU3,n

FDC‐1‐1 Single 

1 

271  80  Idle  130  30  ‐  ‐  3.4  2.0  ‐  ‐  0.2 

503  70  Idle  140  90  ‐  ‐  12.2  7.6  ‐  ‐  1.2 

693  60  147  150  140  ‐  ‐  23.6  14.0  ‐  ‐  1.3 

FDC‐2‐1 Single 

1 

281  75  Idle  130  50  ‐  ‐  3.7  2.0  ‐  ‐  0.0 

478  70  Idle  120  80  ‐  ‐  10.3  5.7  ‐  ‐  0.6 

481  70  90  120  80  ‐  ‐  11.0  6.1  ‐  ‐  0.4 

652  75  155  165  145  ‐  ‐  24.7  15.6  ‐  ‐  0.6 

FDC‐3‐1 Single 

1 

233  80  Idle  130  40  ‐  ‐  3.5  2.3  ‐  ‐  0.0 

503  70  Idle  120  90  ‐  ‐  11.4  6.6  ‐  ‐  0.9 

664  60  130  135  125  ‐  ‐  20.7  13.9  ‐  ‐  3.3 

732  75  165  180  155  ‐  ‐  26.4  17.6  ‐  ‐  3.5 

FDC‐4‐1 Siamese 

1 

448  75  Idle  125  60  ‐  ‐  1.2  1.1  ‐  ‐  5.5 

642  60  110  120  105  ‐  ‐  2.4  8.5  ‐  ‐  14.6 

618  60  130  130  120  ‐  ‐  2.7  5.8  ‐  ‐  16.7 

761  70  180  180  165  ‐  ‐  3.2  12.0  ‐  ‐  24.9 

FDC‐4‐2 Siamese 

2 

906  65  90  90  90  70  ‐  5.8  8.5  8.3  ‐  8.1 

1073  60  120  120  110  95  ‐  7.7  9.3  10.5  ‐  9.2 

1232  50  150  150  138  115  ‐  10.1  12.5  14.2  ‐  12.5 

1345  40  170  170  155  135  ‐  11.9  17.5  16.3  ‐  17.5 

1492  20  200  200  178  160  ‐  13.7  19.3  19.1  ‐  20.3 

FDC‐5‐1 Siamese 

1 

552  65  Idle  120  85  ‐  ‐  1.4  1.3  ‐  ‐  8.3 

700  75  140  145  134  ‐  ‐  3.1  6.5  ‐  ‐  17.1 

777  70  180  180  164  ‐  ‐  4.1  8.2  ‐  ‐  20.9 

January 8, 2016

1505254.000 7849

52

Test ID FDC Type

Flow to Inlet(s)

Total Discharge

Flow [gpm]

Pumper Pressure Data [psi] Average Pressure [psi] (b) FDC

Pressure Loss [psi]

Intake Pressure

Set Pressure (a)

Pump Pressure

Discharge Pressure

Pp1

Discharge Pressure

Pp2

Discharge Pressure

Pp3 PD,t PU1,n PU2,n PU3,n

FDC‐5‐2 Siamese 

2 

865  66  90  80  85  65  ‐  5.1  8.6  8.1*  ‐  8.4 

982  68  120  120  110  95  ‐  6.9  19.4  19.7*  ‐  18.8 

1298  50  170  170  154  135  ‐  10.5  22.2  23.8*  ‐  22.8 

1445  45  200  200  180  160  ‐  12.8  27.8  24.4*  ‐  28.9 

FDC‐6‐1A Triamese 

1 554  N/A  N/A  N/A  N/A  ‐  ‐  0.28  7.4  ‐  ‐  15.8 

566  N/A  N/A  N/A  N/A  ‐  ‐  0.35  11.4  ‐  ‐  20.1 

FDC‐6‐1B Triamese 

1 

979  N/A  N/A  N/A  N/A  ‐  ‐  0.9  10.6  ‐  ‐  36.9 

1006  N/A  N/A  N/A  N/A  ‐  ‐  0.9  10.4  ‐  ‐  38.3 

1076  N/A  N/A  N/A  N/A  ‐  ‐  1.8  5.9  ‐  ‐  36.9 

FDC‐6‐2 Triamese 

2 

1012  70  90  90  85  80  ‐  1.1  2.3  0.2*  ‐  8.4 

1171  50  120  125  114  110  ‐  1.2  6.0  2.0*  ‐  14.4 

1467  40  170  170  155  155  ‐  1.8  10.4  10.4*  ‐  23.7 

1717  30  200  195  180  177  ‐  2.6  16.8  13.8*  ‐  35.0 

FDC‐6‐3 Triamese 

3 

1420  45  80  85  80  80  90  2.3  7.5  5.1  7.4*  11.5 

1462  40  90  80  80  85  85  1.9  5.6  5.6  4.5*  10.4 

1748  28  100  102  95  80  95  3.5  12.6  9.2  8.3*  18.6 

1755  20  120  120  109  80  110  3.5  10.7  9.2  9.1*  16.7 

1818  10  127  125  118  100  118  3.7  12.4  9.6  8.1*  18.9 

Note: (a) For certain tests, the flow was throttled to achieve a low flow condition (approximately < 90 gpm). (b) A supplemental technique was used to determine certain upstream pressure due to cavitation created by hose orientations during testing (noted by “*”). (c) “N/A” indicates that pumper data was not recorded. (d) “Idle” denotes the idle engine (approximately 700 rpm) as indicated on the pressure set at the pumper control.

January 8, 2016

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Figure 29 Pumper control and pressure gauges

Intake  Pump 

Pp1  Pp3 Pp2 Set