39 – fire engineering report

39

39 – Fire Engineering Report

NSW Department of Education Waitara Public School Redevelopment

Schematic Design Report

Fire Engineering Brief Rev B

21-26108-WA February 2018

GHD | Report for NSW Department of Education - Waitara Public School Redevelopment, 2126108 | i

Executive summary This report is subject to, and must be read in conjunction with, the limitations set out in section

1.5 and the assumptions and qualifications contained throughout the Report.

GHD Pty Ltd has been commissioned, by the NSW Department of Education to develop a

Performance Solution that addresses the nominated design variations from the Deemed-to-

Satisfy (DtS) Provisions of the Building Code of Australia 2016 (BCA) for the project. Furthermore

to demonstrate that the Performance Solution detailed in the Fire Engineering Brief (FEB)

complies with the relevant Performance Requirements of BCA.

The variations from the Deemed-to Satisfy Provisions of the BCA for the proposed demountable

building that are to be assessed are summarised in table 3 below.

The following list primarily relates to the fire safety strategy proposed under the Performance

Solution and does not provide a comprehensive list of fire safety measures required by the DtS

provisions of the BCA. The fire safety measures shall be read in conjunction with the DtS

provisions of the BCA.

Omission of a ceiling with the resistance to the incipient spread of fire of 60 minutest to

Level 4 and the provision of glazed skylights to the roof.

The roof to have a non-combustible covering.

Permit the exit stairways be located adjacent to the northern external wall, Stairway 1 at

grid reference (1, A/B), Stairway 2 at grid reference (4/5, A/B) and Stairway 2 at grid

reference (8/9, A/B).

Provision of a fire rated self closing door set with an FRL of -/60/30 to protect the door

opening between the Back of House area (grid 7/8, A) and Stair 3. Permit the fire isolated

door set to swing against the direction of egress.

Enclosure of the Back of House area with construction that complies with the requirements

of Clause D2.6 of the BCA to create a smoke lobby.

Protection of the door openings to the Back of House area leading to the stage and the

performance store by self-closing door sets that comply with the requirements of Clause 3

of Specification C3.4 of the BCA.

No materials or goods shall be stored within the Back of House area.

All other provisions are to be in accordance with the BCA DtS provisions unless addressed

by a performance solution.

Ensure egress paths and exits to be kept free of obstructions at all times;

All active and passive fire safety measures for the subject building shall comply with the

BCA DtS provisions and relevant Australian Standards with the exception permitted by the

performance solution documented in this Report.

ii | GHD | Report for NSW Department of Education - Waitara Public School Redevelopment, 2126108

Table of contents 1. Introduction..................................................................................................................................... 1

1.1 Project Description ............................................................................................................... 1

1.2 Scope of the Report ............................................................................................................. 2

1.3 Relevant Stakeholders ......................................................................................................... 2

1.4 Referenced Documentation ................................................................................................. 2

1.5 Scope and Limitations.......................................................................................................... 3

2. Non-compliance Issues to be Assessed ........................................................................................ 4

2.1 Building Regulatory Objectives ............................................................................................ 4

2.2 Variations from Deemed-to-Satisfy Provisions .................................................................... 4

2.3 Compliance with the NCC .................................................................................................... 4

2.4 Meeting the Performance Requirements ............................................................................. 4

2.5 Performance Solutions......................................................................................................... 5

2.6 Assessment Methods........................................................................................................... 5

3. Building and Occupant Characteristics .......................................................................................... 6

3.1 Principal Building Characteristics ........................................................................................ 6

3.2 Dominant Occupant Characteristics .................................................................................... 9

4. Hazard Assessment and Fire Protection Measures .................................................................... 10

4.1 Nature of Building Use and Hazard Assessment .............................................................. 10

4.2 Fire Safety Measures ......................................................................................................... 10

4.3 Fire Stations ....................................................................................................................... 12

5. Assessment Methodology and Acceptance Criteria .................................................................... 13

5.1 General .............................................................................................................................. 13

5.2 Spread of Fire .................................................................................................................... 13

6. Trial Design for Performance Solution No 1: Omission of a fire rated ceiling to Level 4 ............. 15

6.1 Prescriptive Requirements ................................................................................................. 15

6.2 Proposed Performance Solution ........................................................................................ 15

6.3 Methodology and Acceptance Criteria ............................................................................... 16

6.4 Analysis .............................................................................................................................. 17

6.5 Outcomes ........................................................................................................................... 20

7. Trial Design for Performance Solution No 2: Distance between exits ......................................... 22




7.4 Approach ............................................................................................................................ 23

7.5 Conclusion and Consideration of Performance Requirement ........................................... 23

8. Trial Design for Performance Solution No 3: A doorway opens directly into a fire-

isolated stairway on Level 1 from a back of house area .............................................................. 25



GHD | Report for NSW Department of Education - Waitara Public School Redevelopment, 2126108 | iii


8.4 Approach ............................................................................................................................ 26

8.5 Conclusion and Consideration of Performance Requirement ........................................... 27

9. Fire Safety Measures ................................................................................................................... 28

Table index Table 1 Stakeholders ........................................................................................................................ 2

Table 2 Architectural Drawings ......................................................................................................... 2

Table 3 Variations from DtS Requirements ...................................................................................... 4

Table 4 BCA Building Parameters .................................................................................................... 6

Table 5 Occupants Characteristics ................................................................................................... 9

Table 6 Relevant Sub-Systems ...................................................................................................... 11

Table 7 Fire Stations near the subject building ............................................................................... 12

Table 8 Acceptance Criteria of Heat Flux for Fire Spread (kW/m2) ................................................ 14

Table 9 Fire Scenarios .................................................................................................................... 19

Table 10 Radiation Levels ................................................................................................................ 20

Figure index

Figure 1 Location of Proposed New Classroom Building .................................................................. 1

Figure 2 Waitara Public School Site Plan .......................................................................................... 6

Figure 3 Waitara Public School Site Plan .......................................................................................... 7

Figure 4 Myra Street View .................................................................................................................. 7

Figure 5 Elevations ............................................................................................................................ 8

Figure 6 Separating distances between Classroom Building, Building 5HB & the Library .............. 16

Figure 7 Location of the Classroom Building, Building M & Library ................................................. 18

Figure 8 Elevations of the Classroom Building, Building M & Library .............................................. 18

Figure 9 Exit Stairway 3 & back of House area ............................................................................... 26

Appendices Appendix A – Architectural Drawings

Appendix B – Calculation Sheets

1 | GHD | Report for NSW Department of Education - Waitara Public School Redevelopment, 2126108

1. Introduction 1.1 Project Description

GHD Pty Ltd has been commissioned, by the NSW Department of Education to develop a

Performance Solution that addresses the nominated design variations from the Deemed-to-

Satisfy (DtS) Provisions of the Building Code of Australia 2016 (BCA) for the project. Furthermore

to demonstrate that the Performance Solution detailed in the Fire Engineering Brief (FEB)

complies with the relevant Performance Requirements of BCA.

The proposed development consists of:

The demolition of the Kindergarten Building, Before & After School Care Building, Special

Program Building and Hall & Canteen Building;

Removal of the demountable buildings no. 1-8 and 10-14;

To construct a new four (4) storey classroom building (the “Classroom Building”) including

learnings spaces, hall, library and OSHC facilities and amenities.

The following figure 1 shows the location of the Classroom Building within the boundaries of

Waitara Public School.

Figure 1 Location of Proposed New Classroom Building

Proposed four (4) storeys classroom building


1.2 Scope of the Report

This report documents the fire engineering analyses associated with design variation detailed in

Section 2.2 and has been prepared in accordance with performance-based fire engineering

principles as outlined in the International Fire Engineering Guidelines (IFEG)1.

This report is limited to address the design variation associated with the new Classroom Building.

Any existing buildings at Waitara Public School have been specifically excluded from the scope

of this report.

1.3 Relevant Stakeholders

The relevant stakeholders for the project include the following in the table below.

Table 1 Stakeholders

Description Details

Client NSW Department of Education

Consultant Authority Hornsby Shire Council

Project Manager TSA Management

BCA Consultant Metro Building Consultancy

Architect GHD Woodhead

Fire Safety Engineer GHD

1.4 Referenced Documentation

The fire engineering analysis is based on the following information:

Building Code of Australia 2016 Schematic Design / DA Stage Review Report from Metro

Building Consultancy dated 18 August 2017 (Report Reference: 17165R02-Waitara BCA);

Architectural Drawings from GHD Woodhead as detailed in Table 2 and attached in

Appendix A.

Table 2 Architectural Drawings

Drawing No Drawing Titles Revision

21-26108-WD-SD-AR-0000 Cover Sheet, Locality Plan & Drawing List F

21-26108-WD-SD-AR-0200 Site Demolition Plan E

21-26108-WD-SD-AR-1000 Site Set-out Plan F

21-26108-WD-SD-AR-2000 General Arrangement – Level 1 G

21-26108-WD-SD-AR-2001 General Arrangement – Level 2 C



21-26108-WD-SD-AR-2004 General Arrangement – Roof Plan G

21-26108-WD-SD-AR-3000 Building Elevations – Sheet 1 G

21-26108-WD-SD-AR-3001 Building Elevations – Sheet 2 G

21-26108-WD-SD-AR-3100 Building Sections – Sheet 1 G

21-26108-WD-SD-AR-3101 Building Sections – Sheet 2 G

1 Australian Building Codes Board, International Fire Engineering Guidelines, 2005, Canberra: Australian Building Codes Board.


1.5 Scope and Limitations

This report has been prepared by GHD for NSW Department of Education and may only be used and relied on by NSW Department of Education for the purpose agreed between GHD and the NSW Department of Education as set out in section 1.1 of this report.

GHD otherwise disclaims responsibility to any person other than NSW Department of Education arising in connection with this report. GHD also excludes implied warranties and conditions, to the extent legally permissible.

The services undertaken by GHD in connection with preparing this report were limited to those specifically detailed in the report and are subject to the scope limitations set out in the report.

The opinions, conclusions and any recommendations in this report are based on conditions encountered and information reviewed at the date of preparation of the report. GHD has no responsibility or obligation to update this report to account for events or changes occurring subsequent to the date that the report was prepared.

The opinions, conclusions and any recommendations in this report are based on assumptions made by GHD described in this report. GHD disclaims liability arising from any of the assumptions being incorrect.

GHD has prepared this report on the basis of information provided by NSW Department of Education and others who provided information to GHD (including Government authorities), which GHD has not independently verified or checked beyond the agreed scope of work. GHD does not accept liability in connection with such unverified information, including errors and omissions in the report which were caused by errors or omissions in that information.

This report does not consider prescribed fire safety matters that fall within the jurisdiction of the relevant fire service. The report provides a review of documentation to determine the extent of compliance for the nominated fire safety issues. It does not include operational checks of fire safety equipment, verification of construction techniques, fire resistance levels or the witnessing of fire drills or exercises, and should therefore not be treated as a full compliance or conformance audit for any fire safety system. The operational status of systems, items of equipment and staff training should be addressed as part of the enforcement, maintenance, testing, training and management procedures for the building.

This assessment is consistent with the objectives and limitations of the BCA and therefore does not consider

arson (other than as a source of initial ignition), multiple simultaneous ignition sources, use of accelerants,

acts of terrorism, protection of property (other than adjoining property), business interruption or losses, or

personal or moral obligations of the owner/occupier. These issues can be considered, but have been

specifically excluded from the scope of this report.


2. Non-compliance Issues to be Assessed 2.1 Building Regulatory Objectives

The proposed building works are to comply with the BCA 2016 which has the following objectives.

Protect building occupants;

Facilitate the activities of the emergency services personnel;

Protect other buildings from being effected by a fire in the subject building.

The specific objectives in relation to this report are those associated with the relevant

Performance Requirements applicable to the variation from DtS provisions for the proposed

building work.

There is no specific request from the client regarding protection of property, other than adjoining

property as required by the BCA.

2.2 Variations from Deemed-to-Satisfy Provisions

The variations from the Deemed-to-Satisfy (DtS) provisions of the BCA for the subject

development that is to be assessed are summarised in table 3. These issues are to be addressed

using the fire engineering assessment under the Performance Solutions to demonstrate

compliance with the relevant Performance Requirements of the BCA.

Table 3 Variations from DtS Requirements

Relevant BCA Sections and Clauses

DtS Variations Identified Performance Requirements/ Assessment Methods

1 Clause 3.5 of Specification C1.1 Roof: concession

Omission of a ceiling with the resistance to the incipient spread of fire of 60 minutes to Level 4.

CP2 A0.3(a)(i) A0.5(b)(ii)

2 D1.5 Distance between alternative exits

All exit stairs are located on the northern side of Levels 2-4

DP4 & EP2.2 A0.3(a)(i) A0.5(b)(ii)

3 D1.7 Travel via fire-isolated exits

A doorway from a back of house area opens directly into a fire-isolated stairway on Level 1

DP5 A0.3(a)(i) A0.5(b)(ii)

2.3 Compliance with the NCC

Compliance with the NCC (BCA) is achieved by satisfying the Performance Requirements in

accordance with Clause A0.1 of the BCA.

2.4 Meeting the Performance Requirements

Clause A0.2 of the BCA, namely Meeting the Performance Requirements, states that:

The Performance Requirements can only be satisfied by a-

(a) Performance Solution: or

(b) Deemed-to-Satisfy Solution; or

(c) combination of (a) and (b).


The proposed building works are to achieve compliance with the BCA using a combination of the

Deem-to-Satisfy (prescriptive) Provisions and Performance Solution in accordance with A0.2(c).

This report assesses the Performance Solution for the building features that do not meet the DtS

provisions of the BCA, as identified in section 2.2.

2.5 Performance Solutions

Clause A0.3 of the BCA, namely Performance Solutions, states-

(a) A Performance Solution must-

(i) comply with the Performance Requirements; or

(ii) be at least equivalent to the Deemed-to-Satisfy Provisions,

and be assessed according to one or more of the Assessment Methods.

(b) A Performance Solution will only comply with the NCC when the Assessment Methods used

satisfactorily demonstrate compliance with the Performance Requirements.

The Performance Solution will be demonstrated to comply with relevant Performance

Requirements identified according to Clause A0.7.

It is understood that all other features of the subject building comply with the DtS Provisions of

the BCA or as permitted by the relevant certifier and/or consent authority.

2.6 Assessment Methods

Clause A0.5 of the BCA, namely Assessment Methods, states-

The following assessment methods, or any combination of them, can be used to determine that

a Performance Solution or a Deemed-to-Satisfy Solution complies with the performance

requirements, as appropriate:

(a) Evidence to support that the use of a material or product, form of construction or design meets

a Performance Requirement or a Deemed-to-Satisfy Provision as described in A2.2.

(b) Verification Methods such as:

(i) the Verifications Methods in the NCC; or

(ii) such other Verification Methods as the appropriate authority accepts for determining

compliance with the Performance Requirements

(c) Expert Judgement.

(d). Comparison with the Deemed-to-Satisfy Provisions.

The assessment methods of A0.5(b)(ii) will be used to determine compliance with the

Performance Requirement of the BCA as identified in Section 2.2.

The analysis will incorporate the absolute/comparative manners with qualitative/quantitative

methodologies to assess the Performance Solution for compliance with the relevant Performance

Requirements of the BCA.


3. Building and Occupant Characteristics 3.1 Principal Building Characteristics

Waitara Public School is located at Edgeworth David Avenue, Wahroonga, which is a suburb on

the Upper North Shore Sydney in NSW, 22 km northwest of the Sydney CBD as shown in Figure

2.

Figure 2 Waitara Public School Site Plan

The building parameters for the proposed building in accordance with the BCA, are detailed in

Table 4 below.

Table 4 BCA Building Parameters

Description Details

Class 5 (Staff administration) & 9b (Classrooms, hall)

Rise in Storeys (BCA C1.2) Four (4)

Effective Height (BCA A1.1) 10.5 m

Type of Construction A

Floor area 7,027 m2

The Classroom Building will have an effective height less than 25 m.

The Classroom Building will incorporate four storeys including administration, a school hall,

special program rooms, storage and back of house facilities located on the ground floor (Level 1).

The upper floors (levels 2, 3 & 4) will include library areas, common areas, home base learning

areas, an amphitheatre located at level 3, amenities and back of house areas.

The building structure will include reinforced concrete floor slabs, concrete columns and a steel

framed roof structure with metal roof sheeting. The external walls will include lightweight walling

and glazing panels.

The building will be provided with the following services and equipment:

Hydrant and hose reel system (hose reel system to all areas apart from Class Rooms &

associated corridors);

Portable fire extinguishers;

Automatic smoke detection and alarm system;

Waitara Public School


Passenger lift;

Emergency lighting and exit signage

The following figure 3 shows a site plan of the school and the location of the new Classroom

Building and the adjacent Building 5HB and the Library

Figure 3 Waitara Public School Site Plan

The following figure 4 shows a perspective view of the Myrtle Street elevation of the Classroom

Building.

Figure 4 Myra Street View

Building 5HB

Library

Proposed four (4) storey Classroom Building


The following figure 5 shows elevations of the Classroom Building and the glazed high lights to

Level 4.

Northern & Southern Elevations

Eastern & Western Elevations

Figure 5 Elevations

Glazed high lights

Glazed high lights


3.2 Dominant Occupant Characteristics

Occupant characteristics of the Classroom Building are assumed as follows.

Table 5 Occupants Characteristics

Characteristics Details

Distribution and occupants roles

Occupants in the building are expected to be primary school children, teachers and staff.

State and activity at the outbreak of fire

Occupants are generally expected to be awake and alert during the day and as such expect to respond to any cues indicating that an emergency is present.

Physical and mental attributes Teachers, staff and pupils are assumed to be able to perceive a fire risk, interpret fire cues and implement decisions independently in a potential emergency situation. It is expected that teachers and staff will manage the evacuation of the building. Teachers and staff members have been assumed to be of sound mind and body.

Level of assistance required and available

In this analysis occupants with a disability in the building are assumed to be capable of evacuating to an exit either by themselves or with the assistance of others, in particular teachers and staff.

Emergency training and familiarity with the building

It has been assumed that teachers and staff members are familiar with the building’s egress routes and expected to assist pupils and visitors to exit the building in a fire emergency in accordance with a Fire Evacuation Procedure.


4. Hazard Assessment and Fire Protection Measures 4.1 Nature of Building Use and Hazard Assessment

As previously described, the building will form part of a primary school facility and will include

teaching areas, common open areas, storeroom, OOSH kitchen and sanitary facilities.

The most likely source of a fire hazard is expected to be combustibles located within the

teaching areas and the store rooms. The sanitary facilities are more sterile areas in terms of fuel

load, making them less of a fire hazard, it is not expected that flammable and combustible

liquids will be stored within the building

Although classified as 9b building, the fire hazard associated with the use of the building can be

considered to be similar to the fire hazard of a Class 5 tenancy.

The statistical data supporting the above analysis can be found in the NSWFB report that during

the year of 2001/2002 for building types of 'Shop, store, office, storage; the area of fire origin

has been recorded to be: Garage, carport, vehicle storage area 13.4%; Kitchen, cooking area

10.3%; Office 5.9%; Sales, showroom area 5.7%; and Waste or rubbish area, container 5.4%.

It is considered that the most likely source of ignition for a fire within the building will be the

teaching and office areas.

The smoke generated from a potential fire will be to some extent managed by the passive

compartmentation of the building. In the areas with full height partitions, there will be immediate

fire cues only for the occupants in the room of origin and for the rooms directly adjacent.

Occupants in rooms remote from the area of origin will be alerted by the activation of the smoke

detection and alarm system.

It is expected that students will require assistance from the teachers and staff members to

evacuate the building.

4.2 Fire Safety Measures

4.2.1 General

The fire safety measures shall comply with DtS requirements applicable to the Classroom

Building. It shall be the responsibility of the NSW Department of Education to assure that fire

safety systems are regularly maintained.

4.2.2 Passive Fire Protection

Fire rating is required to be provided by construction that will satisfy the requirements of Type A

construction in accordance with the DtS provisions of the BCA.

4.2.3 Active Fire Protection and Fire Fighting Provisions

Fire services and equipment including fire hydrant system, fire hose reel system, portable

extinguishers, automatic smoke detection system with occupant warning, emergency lighting

and exit signs are required to be provided and shall be in accordance with prescriptive

requirements of BCA and applicable Australian Standards.

4.2.4 Fire Safety Subsystems

The preventative and protective measures provided to the sub-systems (as defined in

International Fire Engineering Guidelines) that are affected by the DtS variations are outlined

below.


Table 6 Relevant Sub-Systems

Subsystem Considerations

Sub-system A Fire Initiation and Development and Control

Fire hazard properties of construction materials used within the building are expected to comply with BCA Spec C1.10.

Sub-system B Smoke Development and Spread and Control

Smoke spread is expected to be limited by wall partitions and fire separations in the building.

Subsystem C Fire Spread and Impact and Control

This was considered in the qualitative analysis

Sub-system D Fire Detection, Warning and Suppression

Fire detection provisions are assumed to be in accordance with the DtS Provisions.

Subsystem E Occupant Evacuation and Control

This was considered in the qualitative analysis

Sub-system F Fire Services Intervention

The subject building is considered to have reasonable Fire Brigade access. Appropriate means for Fire Brigade intervention in accordance with the DtS Provisions of the BCA.

The most relevant sub-system is considered to be Subsystem C ‘Fire Spread and Impact and

Control’


4.3 Fire Stations

There are overall philosophical Fire Brigade objectives throughout Australia to protect life,

property and the environment from fire according to the Fire Brigade Intervention Model

(FBIM)2.

Over and above the requirements of the BCA, the Fire Brigade has functions with regard to

property protection and considerations of occupational health and safety for its employees

which are commensurate with the Fire Safety Strategy to be incorporated.

In the absence of specific times, the Fire Engineering Guidelines3 recommends a ten (10) minutes

fire brigade arrival time with a further twenty (20) minutes setup time for city environment. This

result in a total of thirty (30) minutes from ignition to commencement of extinguishment, however,

in most cases the actual fire brigade intervention time is expected to be less than thirty (30)

minutes.

The nearest NSW Fire Brigades are Hornsby and Gordon and the table below describes the

expected fire brigade travel and intervention times.

Table 7 Fire Stations near the subject building

Station location according to FRNSW website accessed November 2017

Approximate distance (km) to the subject building using Google map

Expected travel time (min)

Expected fire brigade intervention time including search & rescue (min)

Hornsby Fire Station 2 Bridge Street, Hornsby

2.3 km 6 min 16 min

Gordon Fire Station 966 Pacific Highway, Gordon

7.1 km 11 min 21 min

2 Australasian Fire Authorities Council, 1997 – Fire Brigade Intervention Model – Version 2.2 – November 2003 3 Fire Engineering Guidelines First Edition, Chapter 13. Fire Code Reform Centre Limited. March 1996.


5. Assessment Methodology and Acceptance Criteria

5.1 General

The objective of fire engineering analysis is to demonstrate compliance with the relevant

Performance Requirements of BCA. The methods of analysis are proposed to be in accordance

with the IFEG is predominantly used to determine compliance with the identified Performance

Requirements.

Due to the nature of the non-compliance issues, a combination of quantitative and qualitative

approach is primarily used to determine the compliance with the identified Performance

Requirements.

5.2 Spread of Fire

5.2.1 The Approach

The proposed methodology for the assessment of the potential for fire spread to or from an

adjoining building is to be based on the calculated radiant heat emitted to or received by the

subject building. The basis of the assessment is that the potential of fire spread should be within

the limits for critical heat flux for typical building materials.

5.2.2 Temperature of Emitting Surface from the Subject Building

Peak external plume temperatures of 900°C, maintained for short periods of time, are reported

by Fire Code Reform Centre4 and Babrauskas5. This temperature is also considered

appropriate for the virtual radiant panel created by an opening on the subject building in post

flashover phase. A uniform temperature of 900°C is adopted for an emitter for a fire spread

scenario.

5.2.3 Acceptance Criteria

IFEG1 Chapter 3.3 Table 3 contains a listing of heat flux required for radiant ignition of plastics

and wood materials. Minimum flux levels for piloted ignition are categorically above 10kW/m2.

The Guide to the BCA also gives some typical examples of the amount of radiant heat

necessary to ignite common materials used in buildings and their construction. The heat flux

levels for unpiloted ignition are 35 kW/m2 and 20 kW/m2 for timber and curtain materials

respectively. For piloted ignition these values are quoted as 20 kW/m2 and 10 kW/m2

respectively.

In the radiant heat assessment, a heat flux level of 20kW/m2 is considered as the ignition criteria

for unpiloted ignition for fire spread by radiation between buildings. A heat flux level of 10kW/m2

is considered as the ignition criteria for piloted ignition.

Table CV2 of the BCA, provides a description of distance between buildings and heat flux

criteria for fire spread between buildings. The acceptance criteria used in the assessment are

listed along with values from BCA Verification Methods in accordance with Table CV2 in the

table below.

4 Alam, T. and Beever, P., ‘Flashover Fires – An Experimental Program’, Centre for Environmental Safety and Risk Engineering,

Victoria University of Technology, CESARE Report 96-002, FCRC Project 4 Technical Report 96-07, October 1996 5 Dr Vytenis Babrauskas, ‘Temperatures in flames and fires’, Fire Science and Technology Inc, February 2006


Table 8 Acceptance Criteria of Heat Flux for Fire Spread (kW/m2)

Radiant Heat Assessment Table CV2 -

between buildings on the same allotment

Unpiloted - 20 kW/m2 at the receiver

Piloted - 10 kW/m2 at the receiver

On boundary 80 kW/m2 2 m from boundary 40 kW/m2 6 m from boundary 20 kW/m2

12 m from boundary 10 kW/m2

The acceptance will be achieved if the calculated heat flux is less than the critical heat flux.

Where a comparative assessment is provided, the heat flux estimated for the proposed

alternative shall be no more than that of a comparable BCA DtS arrangement.


6. Trial Design for Performance Solution No 1: Omission of a fire rated ceiling to Level 4 6.1 Prescriptive Requirements

The relevant DtS Provision, namely Table 3 and Clause 3.5 of Specification C1.1 of the BCA,

says that-

3. Type A Fire-Resisting Construction

3.5 Roof: Concession

A roof need not comply with Table 3 if its covernign is non-combustible and the building-

(a) has a sprinkler system complying with Specification E1.5 installed throughout; or

(b) has a rise in storeys of 3 or less; or

(c) is of Class 2 or 3; or

(d) has an effencive height of not more than 25 m and the ceiling immeately below the roof has a

resistance to the incipient spread of fire to the roof space of not less than 60 minutes.

6.2 Proposed Performance Solution

The provision of a fire rated ceiling has been designed to prevent the spread of fire from the

subject building to the roof space and to adjacent buildings. The provision of a non-combustible

roof covering will protect the subject building from incoming fire from adjacent buildings.

The proposed methodology for the assessment of the potential for fire spread from the

Classroom Building, Building 5HB or the Library will be based on the calculated radiant heat

received to or from the Classroom Building, Building 5HB and the Library.

The basis of the assessment is that the potential of fire spread should be within the limits for

critical heat flux for typical building materials and Table CV2 of the BCA.

The following figure 6 shows the separating distances between the Classroom Building and

Building 5HB and the Library being 6 m.


Figure 6 Separating distances between Classroom Building, Building 5HB & the Library

The performance solution has been designed to address the requirment to provide a ceiling

immediately below the roof with a resistance to the incipient spread of fire to the roof space of

not less than 60 minutes and the provisiojn of glazed sky lights, it is proposed that:


Level 4 and the provision of glazed sky lights to the roof.







6.3 Methodology and Acceptance Criteria

Compliance with the BCA will be achieved by formulating a Performance Solution that complies

with the Performance Requirements of the BCA, as detailed in Section 2.2. The analysis

associated with the assessment of the omission of a fire rated ceiling to Level 4 involves a

combination of absolute and comparative manners with qualitative methodology.

It is to be demonstrated that the omission of a fire rated ceiling resistant to the incipient spread of

fire of not less than 60 minutes to the roof space on Level 4 and the provision of glazed sky lights

will not impact on the possible spread of fire to an adjacent building.

The proposed solution for this alternative solution will be assessed against the relevant

performance requirements as noted in Section 2.2 of this report.

Classroom Building

6 m

6 m

Building 5HB

Library


6.4 Analysis

The proposed methodology for the assessment of the potential for fire spread from the

Classroom Building, Building 5HB or the Library will be based on the calculated radiant heat

received by the Classroom Building, Building 5HB and the Library.

The basis of the assessment is that the potential of fire spread should be within the limits for

critical heat flux for typical building materials.

The radiation programme of Firewind V3.6 is used to estimate the radiant heat flux between

buildings. Below is a brief description of the programme.

The following assumptions have been made for the above values:

Emissivity of the emitter is assumed to have a value of 1 and entered as the opening

being 100% open.

Configuration view factor, built into the program takes into account the intensity of

radiation received by a surface remote from the emitters and its geometrical relationship.

The temperatures proposed for the emitting surfaces are depended on a number of

factors and detailed below.

This report will model a fire within the roof of the Classroom Building and estimate the potential

radiation received at Building 5HB and the Library as scenarios 1 and 2. The report will also

model fires within Building 5HB and the Library as scenarios 3 and 4.

Fire within the roof of the Classroom Building

This report will model a fire at the roof of the Classroom building and estimate the potential

radiation received at the roof of Building M and the Library Building (Fire scenario 1 and 2).

Fire within the roof of Building M

This report will model a fire at the roof of Building M and estimate the potential radiation

received at the Classroom Building (Fire scenario 3).


Fire within the roof of the Library Building

This report will model a fire at the roof of Library Building and estimate the potential radiation

received at the Classroom Building (Fire scenario 4).

Figure 7 Location of the Classroom Building, Building M & Library

The following elevations in figure 8 show the location of the roofs to the Classroom Building,

Building M and the Library which form potential radiators for the spread of fire between

buildings.

Figure 8 Elevations of the Classroom Building, Building M & Library

Building M

Classroom Building

Library

Roof to Building M

Roof to Library

Roof to Classroom Building

Roof to Classroom Building


The following Table 8 describes the proposed fire scenarios.

Table 9 Fire Scenarios

Scenario Radiation Source Radiation Received

1 Classroom Building Building M

2 Classroom Building Library

3 Building M Classroom Building

4 Library Classroom Building

The following parameters apply to the radiation modelling:

Scenario 1: Classroom Building

Horizontal Radiator: Roof perimeter 6 m (w) x 1 m (h) Temperature of radiator: 900 OC (average) Horizontal distance to receptor: 6 m (worse scenario) Horizontal offset of exposed window to centre of radiator: 0 m (worse scenario) Vertical offset from centre of radiator: -3.9 m The calculated level of radiation received at: Building M 3.018 kW/m2.

Scenario 2: Classroom Building

Radiator: Roof perimeter 6 m (w) x 1 m (h) Temperature of radiator: 900 OC (average) Horizontal distance to receptor: 6 m Horizontal offset of exposed window to centre of radiator: 0 m (worse scenario) Vertical offset from centre of radiator: -7 m The calculated level of radiation received at: Library 1.472 kW/m2.

Scenario 3: Building M

Horizontal Radiator: Roof panel 6 m (w) x 6 m (l) Temperature of radiator: 900 OC (average) Horizontal distance to receptor: 0 m (worse scenario) Horizontal offset of exposed window to centre of radiator: 0 m (worse scenario) Vertical offset from centre of radiator: 3.9 m The calculated level of radiation received at: Classroom Building 5.489 kW/m2.

Scenario 4: Library Building

Horizontal Radiator: Roof panel 6 m (w) x 6 m (l) Temperature of radiator: 900 OC (average) Horizontal distance to receptor: 0 m (worse scenario) Horizontal offset of exposed window to centre of radiator: 0 m (worse scenario) Vertical offset from centre of radiator: 1.5 m The calculated level of radiation received at: Classroom Building 5.991 kW/m2.


The predicted radiation levels have been summarised in the following Table 9.

Table 10 Radiation Levels

Scenario Radiation Source Radiation Received Radiation kW/m2

Acceptance Criteria kW/m2

Satisfactory

1 Classroom Building

Building M 3.018 20 Yes

2 Classroom Building

Library 1.472 20 Yes

3 Building M Classroom Building 5.489 20 Yes

4 Library Classroom Building 5.991 20 Yes

Calculation sheets have been attached to Appendix B.

6.5 Outcomes

Fire Spread from the adjacent buildings

The radiant heat flux from a fire within the Classroom Building has been calculated to be 3.018

and 1.472 kW/m2 to Building M and the Library. Conversely, the radiant heat flux for a fire within

Building M and the Library to the Classroom Buildings has been calculated to be 5.489 and

5.991 kW/m2.

The metal roof sheeting roof the Classroom Building including the glazed highlights could

withstand the calculated heat flux and meet the acceptance criteria detailed in Section 5.2.4.

The roof and external walls to Building M and the Library could also withstand the calculated

heat flux.

The calculated heat flux levels for fire spread from or to the adjoining building and meets the

acceptance criteria.

6.6 Conclusion and Consideration of Performance Requirements

In order for the Performance Solution to comply with the Performance Requirements of the

BCA, the solution must demonstrate that each of the DtS variations identified in Section 2.2

complies with the corresponding Performance Requirement clauses. The proposed use of the

Classroom Building has been found to comply with the Performance Requirements of CP1 and

CP2 as follows.

Performance Requirements CP1 Considerations

A building must have the elements which will to the degree necessary, avoid the spread of fire-

(a) the function or use of the building; and This was considered relevant for the engineering analysis

(b) the fire load; and

(c) the potential fire intensity; and

(d) the fire hazard; and

(e) the height of the building; and This has been considered similar to a DtS building.

(f) its proximity to other property; and This was considered relevant for the engineering analysis for separating distances to side boundaries.


(g) any active fire safety systems installed in the building; and

This has been considered similar to a DtS building.

(h) the size of any fire compartment; and

(i) fire brigade intervention; and

(k) the evacuation time

Performance Requirements CP2 Considerations

(a) A building must have the elements which will to the degree necessary, avoid the spread of fire-

(a)(i) to exits; and This was considered not relevant for the engineering analysis

(a)(ii) to sole occupancy units and public corridors

Not applicable to a Class 9b building.

(a)(iii) between buildings; and This was considered relevant for the engineering analysis

(a)(iv) in a building.

(b) Avoidance of the spread of fire referred to in (a) must be appropriate to-

(b)(i) The function or use of the building; and

(b)(ii) the fire load; and

(b)(iii) the potential fire intensity; and This was considered relevant for the engineering analysis to calculate levels of radiant heat flux.

(b)(iv) the fire hazard; and This was considered relevant for the engineering analysis

(b)(v) the number of storeys in the building; and

(b)(vi) its proximity to other property; and This was considered relevant for the engineering analysis for separating distances between buildings.

(b)(vii) any active fire safety systems installed in the building; and

This has been considered similar to a DtS building.

(b)(viii) the sized of any fire compartment; and

(b)(ix) fire brigade intervention; and

(b)(x) other elements they support; and

(b)(xi) the evacuation time.


7. Trial Design for Performance Solution No 2: Distance between exits 7.1 Prescriptive Requirements

The relevant DtS Provision, namely Clause D1.5 says:


Under a Performance Solution in respect of the DtS Provision of the BCA identified in Section 2.2,

it is proposed:




Ensure egress paths and exits are kept free of obstructions at all times.







Due to the nature of the non-compliances, a qualitative approach is primarily used to determine

compliance with the identified Performance Requirements.

Compliance with the BCA is to be achieved by formulating the Performance Solutions which

comply with the Performance Requirements of the BCA, as detailed in Section 2.2.

The Performance Solution associated with the location of the fire isolated stairway exits is

assessed using a qualitative approach. The associated acceptance criteria are that an

acceptable level of safeguards is provided to maintain adequate escape routes for the building.


7.4 Approach

The exit system for the building incorporates three fire isolated stairways which are located

along the northern wall of the building. The stairways provide alternative exits for levels 2, 3 and

4 and are located approximately 21.6 m apart.

Clause D1.5 (a) says in part “Exits that are required as alternative means of egress must be (a)

distributed as uniformly as practicable within or around the storey served…”. Clause D1.5 (a)

provides a degree of flexibility in the location of alternate exits.

However, Clause D1.5 (b) and (c) (iii) and (d) goes on to provide a specification for the location

of two or more exits in relation to a minimum and maximum separation distance between exits.

Such that each exit is not less than 9 m apart and a maximum separating distance of 60 m and

“so that alternative paths of travel do not converge such that they become less than 6 m apart”.

The location of the three fire isolated stairway exits comply with these requirements of the BCA.

It is considered that the location of the fire isolated stairway exits satisfy the performance

requirements of DP4 and EP2.2.

7.5 Conclusion and Consideration of Performance Requirement

Based on the above assessment the proposed fire safety measures for the Performance

solution have been found to comply with the Performance Requirement of DP4 and EP2.2.

Performance Requirement DP4 Considerations

Exits must be provided from a building to allow occupants to evacuate safely, with their number, location and dimensions being appropriate to

(a) the travel distance; and Considered in the assessment

(b) the number, mobility and other characteristics of occupants; and

Considered in the assessment

(c) the function or use of the building; and Considered in the assessment

(d) the height of the building; and Considered in the assessment

(e) whether the exit is above or below ground level.


Performance Requirement EP2.2 Considerations

(a) In the event of a fire in a building the conditions in any evacuation route must be maintained for the period of time occupants take to evacuate the part of the building so that -

(i) the temperature will not endanger human life; and (ii) the level of visibility will enable the evacuation route to be determined; and (iii) the level of toxicity will not endanger human life


(b) The period of time occupants take to evacuate the referred to in (a) must be appropriate to -

(i) the number, mobility and other characteristics of occupants; and (ii) the function or use of the building; and

These were considered in the egress assessment.


(iii) the travel distance and other characteristics of the building; and

(iv) the fire load; and (v) the potential fire intensity; and (vi) the fire hazard; and

These were considered in the assessment.

(vii) any active fire safety systems installed in the building; and

(viii) fire brigade intervention.


8. Trial Design for Performance Solution No 3: A doorway opens directly into a fire-isolated stairway on Level 1 from a back of house area 8.1 Prescriptive Requirements

The relevant DtS Provision, namely Clause D1.7 says:


Under a Performance Solution in respect of the DtS Provision of the BCA identified in Section 2.2,

it is proposed that:

Provision of a fire rated door set with an FRL of -/60/30 to protect the door opening between

the Back of House area (grid 7/8, A) and Stair 3.

Permit the fire isolated door set to swing against the direction of egress.




performance store by door sets that comply with the requirements of Clause 3 of

Specification C3.4 of the BCA.



Due to the nature of the non-compliances, a qualitative approach is primarily used to determine

compliance with the identified Performance Requirements.

Compliance with the BCA is to be achieved by formulating the Performance Solutions which

comply with the Performance Requirements of the BCA, as detailed in Section 2.2.

The Performance Solution associated with the fire isolation of Stairway 3 is assessed using a

qualitative approach. The associated acceptance criteria are that an acceptable level of

safeguards is provided to maintain the fire isolation of Stairway 3.


8.4 Approach

A fire isolated stairway allows occupants to evacuate from a building via a relatively safe area

and secondly the fire isolated stairway also provides an area for fire fighting operations. The

intent of the BCA is to ensure that a door opening into a fire isolated stairway leads from a

public area.

The proposed performance solution has been designed to maintain the fire isolation and

integrity of Stairway 3 by the use of the Back of House area as a smoke lobby and the

protection of the opening between the back of House area and Stairway 3 by a self closing fire

rated door set with an FRL of -/60/30.

The following figure 9 provides a part floor plan of Stair 3 and the adjacent Back of House area

and the proposed works encompassed by the Performance Solution.

Figure 9 Exit Stairway 3 & back of House area

The purpose of the smoke lobby is to provide a buffer zone to prevent smoke and hot gases

from a fire situation entering the fire isolated stairway.

It is considered that the location of the fire isolated stairway exits satisfy the performance

requirements of DP5.

Protect opening with self closing fire rated door set with an FRL of -/60/30, opening against the direction of egress

Protect openings to the Back of House area with self closing door sets that comply with the requirements of Clause 3 of Specification C3.4 of the BCA.

Enclosure of the Back of House area with

construction that complies with the

requirements of Clause D2.6 of the BCA to

create a smoke lobby


8.5 Conclusion and Consideration of Performance Requirement

Based on the above assessment the proposed fire safety measures for the Performance

solution have been found to comply with the Performance Requirement of DP5.

Performance Requirement DP5 Considerations

To protect evacuating occupants from a fire in the building exits must be fire isolated to the degree necessary, appropriate to-

(a) the number of storeys connected by the exits; and


(b) the fire safety system installed in the building; and

(c) the function or use of the building; and

(d) the number of storeys passed through by the exits; and

(e) fire brigade intervention.


9. Fire Safety Measures This report has been prepared in accordance with performance-based fire engineering principles

as outlined in the International Fire Engineering Guidelines to demonstrate that the Performance

Solutions outlined in this report, comply with the Performance Requirements of BCA. All other

building parameters are understood to meet the DtS requirements of the BCA or as permitted by

the BCA consultant and/or relevant consent authority.

Fire safety strategy for the proposed development is to be provided by a combination of the

prescriptive and alternative fire safety measures in order to provide an acceptable level of fire

safety within the subject building.

The following list primarily relates to the fire safety strategy proposed under the Performance

Solution and does not provide a comprehensive list of fire safety measures required by the DtS

provisions of the BCA. The fire safety measures shall be read in conjunction with the DtS

provisions of the BCA.


Level 4 and the provision of glazed skylights to the roof.





Provision of a fire rated self closing door set with an FRL of -/60/30 to protect the door

opening between the Back of House area (grid 7/8, A) and Stair 3. Permit the fire isolated

door set to swing against the direction of egress.




performance store by self-closing door sets that comply with the requirements of Clause 3

of Specification C3.4 of the BCA.




Ensure egress paths and exits to be kept free of obstructions at all times;




Appendices

Appendix A – Architectural Drawings

Appendix B – Calculation Sheets

Fire Scenario 1

Fire Scenario 2

Program Radiation

(All dimensions are in meters)

X-sources:Radiation temperature 900°°

Distance Offset Size of source Opening X Yx Zx Y Z % 6 0 -3.9 6 1 100

RADIATION MAP XY

PX

Y -4.00

-4.00

4.00

4.00 Radiation flow, kW/m²:

1.500

2.150

2.800

3.450

4.100

Nodal radiation data, kW/m²:

Y \ X 4.00 2.00 0.00 -2.00 -4.00

4.00 2.188 2.602 2.209 1.726 1.331

2.00 3.353 3.584 2.784 2.042 1.509

0.00 3.846 3.999 3.018 2.166 1.577 -2.00 3.353 3.584 2.784 2.042 1.509

-4.00 2.188 2.602 2.209 1.726 1.331

Orientation of maximum radiation flow

at point P(0,0,0):

Program Radiation

(All dimensions are in meters)

X-sources:Radiation temperature 900°°

Distance Offset Size of source Opening X Yx Zx Y Z % 6 0 -7 6 1 100

RADIATION MAP XY

PX

Y -4.00

-4.00

4.00


0.900

1.000

1.100

1.200

1.300


Y \ X 4.00 2.00 0.00 -2.00 -4.00

4.00 0.711 1.108 1.186 1.094 0.946

2.00 0.892 1.347 1.392 1.243 1.047

0.00 0.966 1.443 1.472 1.299 1.085

-2.00 0.892 1.347 1.392 1.243 1.047 -4.00 0.711 1.108 1.186 1.094 0.946


at point P(0,0,0):

Fire Scenario 3

Fire Scenario 4

Program Radiation

(All dimensions are in meters)Z-sources:

Radiation temperature 900°°

Distance Offset Size of source Opening Z Xz Yz X Y %

3.9 9 0 6 6 100

RADIATION MAP XY

PX

Y -3.90

-3.90

3.90


3.00

6.50

10.00

13.50

17.00


Y \ X 3.90 1.95 0.00 -1.95 -3.90

3.90 12.51 7.366 4.419 2.776 1.830

1.95 16.85 9.180 5.188 3.127 2.003

0.00 18.64 9.914 5.489 3.260 2.067

-1.95 16.85 9.180 5.188 3.127 2.003

-3.90 12.51 7.366 4.419 2.776 1.830


at point P(0,0,0):

Program Radiation

(All dimensions are in meters)Z-sources:

Radiation temperature 900°°

Distance Offset Size of source Opening Z Xz Yz X Y %

7 9 0 6 6 100

RADIATION MAP XY

PX

Y -3.90

-3.90

3.90


4.00

5.75

7.50

9.25

11.00


Y \ X 3.90 1.95 0.00 -1.95 -3.90

3.90 9.889 7.166 5.046 3.550 2.532

1.95 11.77 8.287 5.675 3.900 2.731

0.00 12.52 8.718 5.911 4.029 2.803

-1.95 11.77 8.287 5.675 3.900 2.731

-3.90 9.889 7.166 5.046 3.550 2.532


at point P(0,0,0):

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39 – fire engineering report

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