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2014 Ngo, Alan University of British Columbia 6/16/2014 Evaluation of Fire Flow Methodologies and Sprinklering Parkade Studies for UBC

Fire Flow Methodologies and Sprinklering Parkade Studies-R03

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2014

Ngo, Alan

University of British Columbia

6/16/2014

Evaluation of Fire Flow Methodologies and Sprinklering Parkade Studies for UBC

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Table of Contents

EXECUTIVE SUMMARY .................................................................................................................................. 2

1. INTRODUCTION ......................................................................................................................................... 3

1.2 Background ................................................................................................................................... 3

1.3 Current Concerns .......................................................................................................................... 4

2. LITERATURE REVIEW (RESEARCH AND REVIEW) ....................................................................................... 6

2.1 Existing Fire Flow Methodologies ................................................................................................. 6

2.1.1 Insurance Service Office Method – ISO (US) ............................................................................. 7

2.1.2 Fire Underwriters Survey – FUS (Canada) ................................................................................. 7

2.1.3 International Fire Code (IFC) and National Fire Protection Agency (NFPA 1)(US) .................... 7

2.1.4 Ontario Building Code – OBC (Canada) ..................................................................................... 8

2.1.5 Särdqvist, Thomas, and Baldwin Methods (UK, UK, US) ........................................................... 8

2.1.6 Iowa State University Method - ISU (US) .................................................................................. 9

2.1.7 Illinois Institute of Technology Research Institute Method - IITRI (US) .................................... 9

2.1.8 National Fire Academy Method - NFA (US)............................................................................... 9

2.1.9 3D Firefighting Method – 3D (US) ........................................................................................... 10

2.1.10 American Water Works Association Method – AWWA – M31 (US) ....................................... 10

2.1.11 National Fire Protection Agency Method – NFPA 5000 (US) .................................................. 10

3. ASSESSMENT OF THE FIRE FLOW METHODOLOGIES .............................................................................. 11

3.1 Comparison of Selected Calculation Methods ............................................................................ 11

3.2 Fire Flow Requirements .............................................................................................................. 13

3.3 Calculating Fire Flow Requirements ........................................................................................... 14

4. CONCLUSION AND RECOMMENDATION ................................................................................................ 16

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EXECUTIVE SUMMARY

The estimation of fire flow needs for campus fire protection has been done using conservative methodologies. Concerns have arisen as to whether the above ground parkades require fire sprinkling and whether fire fighting supply estimation has been overly conservative. A review of the calculations done to date indicates that the assumptions made were excessively conservative and do not reflect the nature of building design on campus. Building Code does not require sprinkling for the above ground parkades.

A number of estimation methods were examined and a preferable methodology has been found. It has also been found that a more reasonable method of determining the parkade fire fighting needs is available. It is recommended that University of British Columbia Point Grey Campus (UBCPGC) should:

1. Adopt the AWWA – M31 method in determining required fire flow on Sprinklered and non-sprinklered buildings within the UBCPGC.

2. Review and update the required fire flow (RFF) on all major buildings and boundaries of each fire zone within UBCPGC (i.e. reduce the number of fire zones if possible).

3. Double check to ensure that no unprinklered buildings that dominate in any of the fire flow zones.

4. Update the hydraulic water distribution computer model by applying AWWA – M31 method. 5. Re-assess the required upgrades (recommended by the consultants) on the water distribution

system to support development growth throughout campus to year 2030. 6. Apply NFPA 1 method when determining RFF on open parking structures (parkades).

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1. INTRODUCTION

The basic method for controlling building fires by fire departments is by applying manual hose line or water monitors through the use of water. This water can come from a municipal water supply, a private water supply, or from the fire department itself (i.e., water tenders). Water applied to a fire accomplishes two things. First, it alleviates, and subsequently removes the heat produced by the fire, thereby preventing that heat from raising the temperature of unignited material to the ignition point. Second, water not converted to steam by the heat of the fire is available to cool material not yet ignited (Hughes, 2014). In order to effectively fight a fire, the water supply available must be adequate for the threat from the building and contents. The water requirements (or required fire flow) for firefighting include the rate of flow, the residual pressure required at that flow, the flow duration, and the total quantity of water required. As described in the National Fire Protection Agency (NFPA) Handbook, the American Water Works Association (AWWA) defines the required fire flow (RFF) as “the rate of water flow, at a residual pressure of 138kPa (20 psi) and for a specified duration, that is necessary to control a major fire in a specific structure”.

1.1 Purposes of the Study There are a number of methods currently used to calculate required water flow rates for sprinklered and non-sprinklered properties. These methods are, in general, based on decades-old criteria derived using data from actual fires and a few of the methods originated with American University research projects, funded by the insurance industry. Over the years, building construction methods, building contents, and fire suppression equipment and tactics have changed. Each fire flow methodology may define the objective of the RFF differently. The purposes of this report are to review and assess the appropriateness of currently required fire flow methodologies, and to provide recommendations to senior management based on the best practice and the most acceptable methods with the least risk from all the findings, and for making an informed decision on whether fire flow should be applied to parkades within the University of British Columbia Point Grey Campus (UBCPGC).

1.2 Background The last set of comprehensive utility master plans was completed by University of British Columbia (UBC) in 2001. Since then, UBC has undertaken many of the servicing improvements proposed in the original plan. In 2010, UBC Campus and Community Planning (C&CP), with the recommendations from UBC Utilities, had engaged an engineering consultant to complete the Integrated Water Master Plan (IWMP), as a strategy to support its commitment to sustainability, and to reduce its demand on infrastructure by increasing the efficiency of how water is used on campus. This plan focused on the three current water based utility functions within UBCPGC – portable water distribution system, sanitary sewer collection system, and stormwater collection system. It evaluated the capacity of these systems to service the growth of the campus over the next 20 years as outlined in the 2030 Campus Plan and identified upgrades that are required. As part of the portable water distribution system analysis, both the maximum daily demand (for consumption) and required fire flows (RFF) were analyzed. The maximum daily demands were calculated based on the gross square metres (GSM) of the buildings and population density; whereas the RFF for the portable water distribution system were analyzed from the

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three (3) different RFF studies conducted by the Fire Underwriters Survey (FUS), a subsidiary of SCM Risk Management Services, and formerly CGI and Insurers’ Advisory Organization, in 1996, 2003, and 2010.

In 1996, FUS conducted a comprehensive set of RFF calculation for the UBCPGC and another RFF analysis in 2003; however, due to the lack of funding, the 2003 analysis was not completed. Since the 1996 and 2003 studies, a significant number of new buildings have been constructed; as a result, fire zone boundaries and associated RFFs have changed accordingly. During preparation of the IWMP, the FUS method was used to update the RFF and boundaries of each fire zone. Due to limited time and budgetary constraints, a comprehensive analysis could not be completed for the IWMP. The fire zones and associated RFFs were estimated on a “governing buildings” approach. Seventeen (17) Fire Flow Demand Zones (FFDZs) were identified and grouped in these studies (See Appendix A). Each fire zone was reviewed to determine which building(s) had the highest required fire flow(s). The RFF for the governing building(s) in each zone was used as the minimum fire flow criteria in determining required water system upgrade works within the University of British Columbia Point Grey Campus (Urban Systems, 2010).

1.3 Current Concerns Through the IWMP it was determined that the parkades, which are currently unsprinklered represent the largest fire flow requirement on campus and significantly exceed current fire zone ratings. It was identified that there was a significant difference in fire flow requirements for parkades, with and without sprinklers. Table 1 below outlines the six (6) existing parkades with their respective RFFs.

Table 1 UBC Existing Parkade Fire Flow Requirements

Parking Structures Fire Flow Zone

FUS Estimated for Unsprinklered

Structure (L/s)

Fire Flow Requirements by

zone (L/s)

Fire Flow Requirement with

Sprinklers (L/s) Fraser River Parkade K 370 200 200 Health Sciences parkade D 470 383 267

Rose Garden Parkade* F 233 233 233

Thunderbird Parkade D 500 383 250 North Parkade B 450 250 250 West Parkade L 500 267 267

*Sprinklers already present.

Upon completion of the IWMP, the consultant had convinced C&CP to look more closely at the fire flow requirements for each of the parkades and complete a business case study by providing two optional solutions to achieve the fire flow requirements where deficiencies exist. Option 1 is to construct infrastructure required to provide adequate fire flow to all unsprinklered parkades via surrounding hydrants; and option 2 is to retrofit parkades with sprinkler systems to provide adequate fire protection (Urban Systems, 2011).

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A detailed analysis in this study concluded that infrastructure upgrades were needed to satisfy the unsprinklered fire flow requirements to two of the six existing parkades - the Health Sciences and Thunderbird Parkades. It was determined that available fire flow in the zones (zones B, F, K and L) containing Fraser River, North and West parkades far exceeds the estimated 2030 fire flow requirements; therefore, the unsprinklered RFFs at the Fraser River, North and West parkades can be achieved without any additional upgrades. Table 2 below presents the parkades that do not satisfy the unsprinklered 2030 fire flow requirements.

Table 2 UBC Parkade Upgrade Requirements

Parking Structure Upgrades Required Description

Fraser River Parkade No Non sprinklered fire flow achieved without upgrades.

Health Sciences Parkade Yes Minimum residual pressure under 138 kPa (20 psi).

Rose Garden Parkade No Sprinklers already present.

Thunderbird Parkade Yes Minimum residual pressure under 138 kPa (20 psi).

North Parkade No Non sprinklered fire flow achieved without upgrades.

West Parkade No

Minimum residual pressure under 138 kPa (20 psi), however, above 128 kPa (18.6 psi).

The cost of water system upgrades to achieve the unsprinklered fire flow requirements for both Health Sciences and Thunderbird parkades was estimated to be approximately $3,300,000, whereas the cost of sprinklered system installation was approximately $1,200,000. These were 2011 estimations, and life cycle costs for these upgrades were not included in this study.

The consultant recommended C&CP to retrofit both the Health Sciences and Thunderbird parkades with sprinkler system based on the cost comparison above (Urban Systems, 2011).

There have been concerns regarding the use of the FUS method in analyzing RFF to buildings due to the followings:

a. Very conservative approach – FUS had made the assumptions that all UBC buildings were non-fire resistant, and exposure assumptions made were very subjective and conservative.

b. Outdated empirical formula from FUS 1999 document –fire protection engineers demonstrated that the FUS calculations were out of date and resulted in water quantities far in excess of what is actually needed. When the Code experts (including several fire chiefs) expanded the sprinklering provisions in the 1998 Code, they dropped FUS from the BCBC Appendix note A-3.2.5.7.(1).

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c. Contradictory to the intent of Building Code and Fire Protection Standards throughout North America – the FUS method recommends extremely high minimum flows for sprinklered buildings which may be up to ten times the flow recommended by the NFPA/Building Code for sprinklered buildings.

2. LITERATURE REVIEW (RESEARCH AND REVIEW)

2.1 Existing Fire Flow Methodologies As part of the literature research and review, twelve existing fire flow calculation methods have been identified. Seven were examined and are described in subsequent sections. The methods identified come from Canada, the US, and UK. Two types of methods were evaluated – those for building planning (building and/or fire code requirements), and those for on-scene fire service use. The building planning methods account for a range of variables in determining RFF (i.e., building construction, occupancy, fire size, etc.). This allows for building professionals to assess current or future buildings against the existing or planned water supply and adjust accordingly. The on-scene fire flow calculation methods consist of one equation with only one variable (usually the subject area or the enclosed volume) used to determine the fire flow. This allows the firefighters on scene to assess whether they need more hose lines or apparatus to fight the fire. A couple other methods were also reviewed, mainly for the discussion on the parkade sprinklering concerns. The twelve methods researched and identified in this report, along with their countries of origin, are listed below:

Building Planning Methods

1. Insurance Service Office Method – ISO (US) 2. Fire Underwriters Survey – FUS (Canada) 3. International Fire Code –IFC (US) 4. National Fire Protection Agency Methods – NFPA 1 (US) 5. Ontario Building Code Method – OBC (Canada)

On-scene Methods

6. Särdqvist, Thomas and Baldwin Methods (UK, UK and US, respectively) 7. Iowa State University Method – ISU – (US) 8. Illinois Institute of Technology Research Institute Method – IITRI (US) 9. National Fire Academy Method – NFA (US) 10. 3D Firefighting Method – 3D (US, UK, Australia)

Other Methods(Building Planning)

11. American Water Works Association Method – AWWA M31 (US) 12. National Fire Protection Agency Method – NFPA 5000 (US)

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2.1.1 Insurance Service Office Method – ISO (US) The ISO method has been developed as an aid in estimating the amount of water that should be available for municipal fire protection, otherwise known as the required fire flow (RFF). ISO uses the RFF at various buildings within a community in order to evaluate the adequacy of the water supply and delivery system for the purpose of establishing insurance premiums. It also determines the firefighting apparatus, size of apparatus fire pumps, and special firefighting equipment needed in the community. The ISO procedure for establishing fire flows evolved from the original National Board of Fire Underwriters (NBFU) formula, which was used for years to determine the fire flow required in downtown business districts of municipalities. The ISO developed the RFF calculation method through a review of large-loss fires but does not reference any specific data. It was reported that the fire flows arose from ISO field engineers counting the number of hose lines used at actual fire scenes and assuming that one 63.5 mm (2-1/2”) hose supplied 15.8 L/s (250 gpm). This method is only applicable to non-residential, non-sprinklered buildings and residential buildings which are sprinklered or non-sprinklered. The ISO method considers factors such as building construction, occupancy, adjacent buildings and fire communication paths between buildings.

2.1.2 Fire Underwriters Survey – FUS (Canada) Fire Underwriters Survey – FUS, is financed by the Canadian Insurance industry and utilizes technical staff of CGI Risk Management Services (formerly the Insurers’ Advisory Organization Inc.). Its purpose is to survey fire protection conditions in Canadian communities and municipalities, providing data and advisory services to fire insurance underwriters and public officials concerns.

In this method, the total floor area in square metres (including all storeys, but excluding basements at least 50% below grade) in the building being considered while evaluating RFF.

For fire-resistive buildings, there are two options in determining the affected areas – (a) consider the two largest adjoining floors plus 50% of each of any floors immediately above them up to eight will be considered, or (b) consider only the area of the largest floor plus 25% of each of the two immediately adjoining floors, depending on whether the vertical openings are adequately protected. Depending on the type of construction (wood frame, non-combustible and fire-resistive), type of occupancies, exposure, and sprinklering or non-sprinklering, surcharges and deductions will be applied to the RFF evaluation of the building.

A reduction of the fire flow up to 50% will be considered for complete automatic sprinkler protection in the FUS method (FUS, 1999).

It appeared that the FUS guidelines for fire flow calculation and the coefficients/factors (type of construction, occupancies, and exposure) were developed from the Insurance Service Office (ISO) method, with some adjustment and modification to fit in with the Fire Underwriters Survey version.

2.1.3 International Fire Code (IFC) and National Fire Protection Agency (NFPA 1)(US) The International Fire Code (IFC) and NFPA 1, the National Fire Protection Association (NFPA) Fire Code, have very similar methods for determining the RFF. Both codes use tabulated values of the RFF which were based on a simplified ISO method.

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The RFF for buildings other than one- and two-family dwellings and one- and two-family dwellings greater than 465 square metres (NFPA 1) or 334 square metres (IFC) are tabulated in tables B105.1 and 18.4.5.1.2 for the IFC and NFPA 1, respectively (Appendix E). The RFF are based on the type of construction of the building as determined by each code and the calculated fire flow area. Fire flows ranging from 95 L/s (1,500 gpm) to 505 L/s (8,000 gpm) at 138 kPa (20psi) residual pressure. Flow durations between 2 and 4 hours are required based on the fire flow.

In general, the fire flow area is the total floor area of all floor levels of a building. For fire resistive buildings, the fire flow area is the area of the three largest successive floors.

For both IFC and NFPA 1, installation of an approved sprinkler system can reduce the fire flow by up to 50% for one- and two-family dwellings and up to 75% for all other buildings.

2.1.4 Ontario Building Code – OBC (Canada) The Ontario Building Code provides a method for calculating the required water supply quantity and flow rate for fire fighting in non-sprinklered buildings. For sprinklered buildings, only the hose stream demands and durations required by NFPA 13, Standard for the Installation of Sprinkler Systems, are required to be provided. The minimum requirements for water supply quantity are relevant to buildings not serviced by a municipal water supply system. Requirements for buildings serviced by municipal water supply systems, where the water supply duration is not a concern, focus on water supply flow rate (i.e. fire flow) and minimum pressure.

The minimum RFF rates are tabulated based on the minimum water supply as shown in Table 3. For municipal water supplies, the RFF rate must be provided for a minimum of 30 minutes and at a pressure of 138 kPa (20 psi).

Table 3 Ontario Building Code Fire Flow Rate (based on minimum water supply)

Minimum water supply, Q (Litres)

Minimum water supply, Q (gallons) Fire flow rate (L/s) Fire flow rate (gpm)

* * 30 476 ≤ 108,153 ≤ 28,571 45 714

108,153 < Q ≤ 135,192 28,571 < Q ≤ 35,714 60 952 135,192 < Q ≤ 162,231 35,714 < Q ≤ 42,857 75 1,190 162,231 < Q ≤ 190,274 42,857 < Q ≤ 50,265 90 1,429 190,274 < Q ≤ 270,388 50,265 < Q ≤ 71,429 105 1,667

Q > 270,388 Q > 71,429 150 2,381 (*) One-story building with building area not exceeding 600 square metres.

2.1.5 Särdqvist, Thomas, and Baldwin Methods (UK, UK, US) Three studies of actual fire flow used during residential and/or non-residential firefighting operations were conducted in the 1950s, 1970s, and 1990s in the UK and the US. The required fire flow equations from Särdqvist, Thomas and Baldwin have the same correlation except different value in constants. The fire area was likely the entire involved area encountered at the fire scene; building height is not

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considered in these equations. Table 4 below summarizes the fire flow equations from Thomas, Baldwin, and Särdqvist.

Table 4 Fire Flow Equations from Thomas, Baldwin, and Särdqvist

Researcher Fire flow equation (gpm) Location of fires Number of fires

analyzed

Size of fire areas analyzed

(square feet) Thomas (1959) 24.2*A0.5 UK 48 2,150 – 650,000 Baldwin (1972) 4.09*A0.66 Illinois 134 214 – 130,000 Särdqvist (1998) 4.17*A0.57 UK 307 Up to 10,720

The Särdqvist, Thomas and Baldwin methods did not appear to have taken construction types, occupancy types, exposure, and sprinkler system into account.

2.1.6 Iowa State University Method - ISU (US) The Iowa State University (ISU) method is a commonly used method based on the amount of water needed to deplete the oxygen in a confined area, when the water is vapourized into steam by the heat of the fire. This method is unique in that it does not consider occupancy hazard, only the volume of the building to be filled with steam.

A limitation of this method is a result of the assumption that the entire space must be involved in fire. Thus, for a large, open parking structure or other non-compartmented building, use of this method yields RFFs which will be quite large.

2.1.7 Illinois Institute of Technology Research Institute Method - IITRI (US) The IITRI technique was developed from a survey by collecting the data from 134 fires in several occupancy types in the Chicago area to determine the water application rate needed for control as a function of fire area. Reported fires were of differing levels of magnitude, so not to concentrate solely on large-loss fires. Water application rates for the studied fires were calculated through a knowledge of length and diameter of hose used and calculated nozzle pressure. Two RFF formulas were developed based on the curve-fitting analysis of available data points on a graph from the survey results – residential occupancies and other occupancies.

For large, over 2,973 square metres (> ~ 32,000 square feet) non-residential buildings, this method becomes invalid as the fire flow tends to decrease for larger areas due to the negative coefficient on one term in the equation.

2.1.8 National Fire Academy Method - NFA (US) National Fire Academy (NFA) method is a modification of the Iowa State University method (ISU). This method was intended to be used by fire fighters at an incident as a tool to aid in determining the amount of water necessary to fight the fire or for preplanning fire flow requirements for major structures. This basic quick calculation formula only accounts for the length and the width of the involved floor. However, if more than one floor of a multistory building is involved, this formula can be

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expanded to include multiple floors by adding the fire flows for each floor (modified by the percent involvement if less than 100%) to determine the total RFF for the building.

The NFA suggests that the formula is only reliable if four or fewer floors are involved.

2.1.9 3D Firefighting Method – 3D (US) 3D Firefighting (3D) method is a training manual on firefighting techniques and tactics published by the Oklahoma State University Press. This manual was put together by four experienced fire service professional from the US, the UK, and Australia. The manual includes a fire flow calculation method for use by on-scene fire commanders. The tactical flow rate presented in this manual accounts for fire flow required by indirect fire attack, direct fire attack, and water fog attack methods. It is proposed that a minimum tactical flow rate of 0.0062 L/s (0.098 gpm) per 0.093 square metre (one square foot) of compartmental fire involvement (or 0.067 L/s per square metre).

2.1.10 American Water Works Association Method – AWWA – M31 (US) The RFF (or NFF – needed fire flow) listed in Table 5 below is recommended to be used for non-sprinklered one-and two-family dwellings not exceeding two stories in height. For other habitable buildings not listed in Table 5, a maximum required fire flow of 221 L/s (3,500 gpm) is recommended. For a building protected by automatic sprinklers, the RFF is that needed for the sprinkler system, plus hose stream converted to 138 kPa (20 psi) residual pressure, with a minimum of 32 L/s (500 gpm).

Table 5 Required Fire Flow for One- and Two-family Dwellings §

Distance Between Buildings Required Fire Flow (m) (ft) (L/s) (gpm)

more than 30.5 (More than 100) 31.5 (500) 9.5 – 30.5 (31 – 100) 47.3 (750) 3.4 – 9.2 (11 – 30) 63.1 (1,000)

Less than 3.4 (Less than 11) 94.6 (1,400) § Dwellings not to exceed two stories in height.

2.1.11 National Fire Protection Agency Method – NFPA 5000 (US) The origin and development of NFPA 5000 was in 2002 and was the first model building code developed using the full open consensus-based procedures accredited by the American National Standards Institute. The first edition marked the culmination of NFPA’s more than 100 years of experience in developing voluntary consensus-based codes and standards related to the built environment. NFPA codes and standards, as well as the codes and standards of other consensus-based standards development organizations, have addressed almost every aspect of the built environment. In addition, the Code is updated in response to, and, in some cases, in anticipation of, emerging technologies, or as society looks to code developers to address new hazards. NFPA 5000 refers to NFPA 1 and NFPA 13 for Fire Code (2009 edition) and Standard for the Installation of Sprinkler Systems (2007 edition), respectively.

All formulas and equations for the aforementioned RFF methods are provided in Appendix D.

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3. ASSESSMENT OF THE FIRE FLOW METHODOLOGIES

3.1 Comparison of Selected Calculation Methods Seven of the twelve RFF methodologies were examined in details. The building planning methods were calculated by applying the information (involved area, exposure factor, construction type, and occupancy types, etc.) which were used by the Fire Underwriters Survey Public Fire Protection Specialist on the UBCPGC parkades (specifically on Thunderbird and Health Sciences Parkades); whereas the on-scene fire fighting methods, only areas were used for the calculation. The selected seven methods were then summarized graphically by plotting the fire flow as a function of area between 1,000 and 60,000 square metres. The fire flow methodologies produced ranges of flow rates that were sometimes an order of magnitude different from each other (see figures 1 through 3 below). It is expected that the other international approaches not discussed would produce similar differences. On figures 1 and 2, the Baldwin and Thomas methods produced the largest ranges of values for the same size non-sprinklered buildings. However, the range of fire flows required by the International Fire Code (IFC), National Fire Protection Agency (NFPA 1), Fire Underwriters Survey (FUS) and Insurance Service Office were found to be within the 500 L/s to 800 L/s for the effective building area of 60,000 square metres. This was based on the assumptions that these buildings were non fire-resistive, non-combustible occupancies, non-sprinklered, low exposure and that every floor of the entire building was on fire simultaneously.

When comparing the Thomas, Baldwin, and Särdqvist methods, it is found that these three methods are very similar. In general, the Särdqvist method produced lower flow rates than the other methods, up to a factor of three differences for larger fire areas. Baldwin method appeared to be generating the highest flow rates among these three methods.

Both IFC and NFPA 1 methods are very much identical, as such, their fire flows range from 95 L/s (1,500 gpm) to 505 L/s (8,000 gpm) at 138 kPa (20 psi) residual pressure. For construction Types IA and IB (fire resistive, high-rise buildings and mid-rise office, respectively), the maximum RFF is recommended to be 379 L/s (6,000 gpm) for buildings from 27,490 m2 and up.

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Figure 1 Seven RFF Methodologies applied on Thunderbird Parkade (assuming non-fire resistive)

Figure 2 Seven RFF Methodologies applied on Health Sciences Parkade (assuming non-fire resistive)

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Besides the IITRI method, the on-scene methods appear to yield reasonable RFF when a smaller area (~2,000 -3,000 m2) is used; however, for buildings over 3,000 m2, the RFF will be over 200 L/s. These methods tended to provide fire flows are lower than the building planning methods for non-sprinklered buildings for smaller areas. Most of the on-scene methods do not account for sprinkler protection in their calculations, and usually only the individual fire cells (or portion of the building floors) are considered. The IITRI method appears to yield the highest fire flow requirement. However, for large, non-residential buildings over 3,000 m2, this method becomes invalid as the fire flow tends to decrease for larger areas. As such, this method was only for discussion purposes, it was not plotted on the graphs. Figure 3 below shows the differences in magnitude with respect to the RFFs from the on-scene methods for small and larger areas compared to the building planning methods.

Figure 3 On-scene Fire Fighting Methods with small and larger areas versus building planning methods

3.2 Fire Flow Requirements As discussed in the previous sections, all existing UBCPGC parkades possess an extremely high fire flow requirement as calculated by FUS with the exception of Rose Garden Parkade (Rose Garden Parkade is sprinklered). It was determined, through a business case for sprinklering parkades study, that upgrades are needed to satisfy the unsprinklered fire flow requirements to both Health Sciences and Thunderbird Parkades. In the study, it was noted that infrastructure upgrades would only prevent the pressure from dropping below the 138 kPa (20 psi) requirement, but would not provide any other significant benefits to the operation of the water system, during fire flow events at both the Health Sciences and Thunderbird Parkades. The RFFs for both Health Sciences Parkade and Thunderbird Parkade were found to be 470 L/s and 500 L/s, respectively.

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3.3 Calculating Fire Flow Requirements During the reviewing of the literatures, it was discovered that the FUS Public Protection Fire Specialist (FUS Specialist) had made a mistake on total floor area used on Thunderbird Parkade. According to the records provided by Facilities and Capital Planning Department, the actual total floor area (TFA) for Thunderbird Parkade is 59,350 square metres, whereas FUS Specialist used 38,816 square metres in their RFF calculation (35% less than the actual floor area). Conversely, if the correct TFA for Thunderbird Parkade was used by FUS Specialist, the RFF would have been 621 L/s. The following Table 6 shows the Thunderbird Parkade RFF comparison between FUS Specialist (with wrong TFA) calculations and this reports calculations (with the correct TFA using different coefficients on construction type). The calculations are based on FUS method with similar assumptions applied by FUS Specialist.

Table 6 Comparison of Thunderbird Parkade RFF between FUS and This Report

Thunderbird Parkade FUS Specialist (non fire-resistive)

Report (non fire-resistive)

Report (Fire resistive)

Total Effective Area (m2) 38,816 59,350 14,838

Construction Type Coefficient 0.8 0.8 0.6

Occupancies Factor -15% (Low Hazard) -15% (Low Hazard) -15% (Low Hazard) Sprinklered System No No No Exposure Factor +2% +2% +2% Required Fire Flow (L/s) 500 621 233

Similarly, Table 7 below shows the different RFFs from the Health Sciences Parkade from FUS Specialist and this report.

Table 7 Comparison of Health Sciences Parkade RFF between FUS and This Report

Health Sciences Parkade FUS Specialist (non fire-resistive)

Report (Fire resistive)

Total Effective Area (m2) 26,997 9,444 Construction Type Coefficient 0.8 0.6 Occupancies Factor -15% (Low Hazard) -15% (Low Hazard) Sprinklered System No No Exposure Factor +15% +15% Required Fire Flow (L/s) 470 212

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The results from Tables 6 and 7 are graphically shown in Figures 4 and 5 below, respectively.

Figure 4 Comparison of different Coefficients used on Thunderbird Parkade

Figure 5 Comparison of different Coefficients used on Health Sciences Parkade

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4. CONCLUSION AND RECOMMENDATION

There are a number of methods currently used to calculate RFFs for sprinklered and non-sprinklered properties. These methods are, in general, based on decades-old criteria derived using data from actual fires. Over the years, building construction methods, building contents, and fire suppression equipment and tactics have changed. The overall objectives of this report are to review and assess the appropriateness of currently RFF methodologies, and to provide recommendations to senior management based on the best practice and the most acceptable methods with the least risk from all the findings, and for making an informed decision on whether fire flow should be applied to parkades within the University of British Columbia Point Grey Campus.

The required fire flow (RFF) is a number used to evaluate the water system for fire insurance purposes. Actual flow used in fire fighting depends on the nature of the fire and how the fire department approaches the fire. There is no evidence that indicates a marginal shortfall in meeting the RFF can be related to an increase in loss. Inability of the distribution system to fully deliver FUS RFF should not be considered as failure of the system.

Twelve fire flow methodologies were reviewed in this report and seven (7) of them were graphically presented in the previous sections. Similar graphs can be found in Appendix F. While there are no firm rules to follow when comparing the calculations derived from these methods, there are some reasonable conclusions that can be made by comparing the building planning methods and the on-scene fire fighting methods. In general, the building planning methods were more complicated and involved multiple steps and sub-calculations. These methods also typically account for many more variables (i.e , building construction, occupancy, fire size, etc.). The benefit of including more variables related to the building is that if the water supply for a given situation is found to be inadequate (i.e. water supply < minimum required fire flow), adjustments could be made to the building construction or protection features (e.g., adding a sprinkler system) to reduce the RFF. The building planning calculation methods also generally regulate other water supply features such as hydrant quantity and replacement, water supply location, water supply duration, etc.

The on-scene fire flow calculation methods are much simpler. These methods consist of one equation with one variable, either the volume or area of the fire, making them easy and quick to use. This allows the firefighters on scene to assess whether they need more hose lines or apparatus to fight the fire. Other than as a first order approximation, the on-scene methods do not appear to lend themselves for use in codifying requirements.

Both the building planning and on-scene methods provide a large range of possible RFFs for both the Thunderbird and Health Sciences Parkades which were evaluated in this report. Some methods demonstrate reasonable recommendations on the application of the RFFs to sprinklered and non-sprinklered buildings. The AWWA-M31 method appeared to be preferable to other methods due to its reasonable and well-documented procedure for determining the fire flow requirement, and that it is widely accepted by many communities not only across the US, but also Canada.

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Further to the review of the currently available RFF calculation methods, as part of this report, fire flow applied to the parkades is also reviewed. All building structures are generally adhered to a building code, and parkades are considered as building structures, but inhabitable. According to National Fire Protection Agency, an International Codes and Standards Organization, the NFPA 5000 2009 Edition manual (Building Construction and Safety Code) Chapter 2 (Referenced Publications) refers NFPA 1, Fire Code, for all building structures. According to the NFPA 1 – 2012, reference 18.4.5.2.3, it states that the “Required fire flow for open parking structures that are not protected throughout by an approved automatic sprinkler system shall be reduced by 75 percent where all of the following conditions are met:

1. The open parking structure shall comply with NFPA 5000, Building Construction and Safety Code. 2. The open parking structure shall be of Type I (Fire Resistive Non-combustible) or Type II

(Protected Non Combustible) construction. 3. The resulting fire flow shall not be less than 63 L/s (1,000 gpm or 3,785 L/min).” (NFPA 1, 2012)

The supporting rationale for the NFPA 1, Fire Code, is that NFPA 88A, Standard for Parking Structures, 2011 edition, does not require automatic sprinklers in open parking structures of Type I and Type II construction. Accordingly, NFPA 101, Life Safety Code, 2012 edition; and NFPA 5000, Building Construction Safety Code, 2012 edition also do not require automatic sprinklers in open parking structures. NFPA 88A, NFPA 101, NFPA 5000, and ICC International Building Code and its legacy codes all recognize a fire in a non-sprinklered open parking structure will not consume/involve more vehicles than that which could be reasonably extinguished with a few hose lines by the fire department, therefore allowing multi-level, unlimited area open parking structures without automatic sprinklers. This is supported by full-scale fire test data and decades of fire incident data that has shown an automobile fire in an open parking structure is typically limited to the area of origin and few adjacent vehicles (NFPA 1, 2012).

Supported by the findings and conclusions of this study, based on the results obtained from the RFF calculations and analysis on both Thunderbird and Health Sciences Parkades, it is recommended that the University of British Columbia Point Grey Campus should:

1. Adopt the AWWA – M31 method in determining RFF on Sprinklered and non-sprinklered buildings within UBCPGC.

2. Review and update the RFF on all major buildings and boundaries of each fire zone within UBCPGC (i.e. reduce the number of fire zones if possible).

3. Double check to ensure that no unprinklered buildings that dominate in any of the fire flow zones.

4. Update the hydraulic water distribution computer model by applying AWWA – M31 method. 5. Re-assess the required upgrades on the water distribution system to support development

growth throughout campus to year 2030. 6. Apply NFPA 1 method when determining RFF on open parking structures (parkades).