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BUSH FIRE PROTECTION FOR EXISTING DEVELOPMENT

A Guide for Fire Agencies and Land Managers

Note: This Guide does not apply to proposed development on bush fire prone land. For matters relating to bush fire protection requirements for proposed development on bush fire prone land refer to Planning for Bush Fire Protection.

NSW RURAL FIRE SERVICE – Bush Fire Protection for Existing Development 2 of 46

Doc um e n t c on tro l

Re le a s e h is to ry Vers ion Date Au thor Summary of chang es

Draft 1 04/03/15 Mark Hawkins and Patrick Schell

Draft 1.1 22/06/15 Patrick Schell Incorporation of grassland provisions, page referencing and general edits

Draft 2 1/4/2016 Jon Gaibor Modifications made to alternate approach as well reformatting of document

Draft 3 30/5/2016 Jon Gaibor Incorporation of comments from internal staff and external agencies

Re viewe d b y Name Title Date

Jon Gaibor Bush Fire Planning Officer 06/10/15

Patrick Schell Supervisor Bush Fire Planning 7/4/2016

Patrick Schell Supervisor Bush Fire Planning 8/6/2016

Ap pro ve d b y This document must be approved by the project sponsor and relevant director.

Name Title Date

Re la te d doc um e n ts Document name Vers ion

Discussion Paper - Bush Fire Protection for Existing Development


Con te n ts 1 Introduction .................................................................................................................................... 4

1.1 Background ......................................................................................................................... 4

1.2 Dictionary and definitions ..................................................................................................... 5

1.3 Purpose ............................................................................................................................... 6

1.4 Aim ...................................................................................................................................... 6

1.5 Scope .................................................................................................................................. 6

1.6 Limitations ........................................................................................................................... 61.6.1 Bush Fire Science ............................................................................................................7

1.6.2 Fire Scenarios ..................................................................................................................7

1.6.3 Fuel loads ........................................................................................................................7

1.6.4 Human behaviour ............................................................................................................7

1.6.5 Maintenance ....................................................................................................................7

1.7 Legislation and Policy .......................................................................................................... 7

1.8 Review of this Guide ............................................................................................................ 8

2 Applying This Guide ..................................................................................................................... 10

2.1 Property Protection Level Matrix ........................................................................................ 12

3 Assessing Existing Development .................................................................................................. 14

3.1 Classify Development Type ............................................................................................... 14

3.2 Undertake Site Assessment ............................................................................................... 14

4 Acceptable Approach for Risk Treatments ................................................................................... 16

4.1 Existing Residential Development ...................................................................................... 16

4.2 Existing Special Fire Protection Purpose Development (SFPP) ......................................... 17

4.3 Existing Major Buildings ..................................................................................................... 17

5 Alternate Approach for Risk Treatments ....................................................................................... 19

5.1 Existing Residential Development ...................................................................................... 19

5.2 Existing SFPP Development .............................................................................................. 22

5.3 Existing Major Buildings ..................................................................................................... 25

6 Dictionary ..................................................................................................................................... 26

7 References ................................................................................................................................... 28

Appendix 1 – APZ Tables for Existing Residential Development .......................................................... 29

Appendix 2 – APZ Tables for SFPP Development ............................................................................... 35

Appendix 3 – APZ Tables for Major Buildings ...................................................................................... 41


1 Introduction Bush fire management in NSW is a shared responsibility which involves fire authorities, landowners, land managers, planning authorities, local councils and the community. The interface between bushland and urban or rural development is an important aspect of bush fire management. Research continues to emphasise the need to employ a suite of risk treatments in interface areas in order to effectively reduce the bush fire risk (see Section 1.2).

In August 2002, legislative provisions came into effect to proactively address the bush fire risk to life and property in interface areas throughout NSW. These provisions require proposed developments in bush fire prone areas to comply with Planning for Bush Fire Protection. As such, developments that have been assessed and approved under these planning and building requirements should incorporate a range of measures that operate in combination to provide protection against bush fire.

However, many developments located in bushland interface areas in NSW pre-date the August 2002 legislation and have not been designed in accordance with Planning for Bush Fire Protection. Generally, these developments offer little or no protection against bush fire. In many cases, these properties will contain assets that have inadequate separation from potential bush fire hazards and construction standards that do not adhere to current bush fire building requirements. In addition, other aspects of the development such as access arrangements, water and power supply may also be inappropriate from a bush fire protection perspective. For the purposes of this Guide, a building or part of a building that has not been assessed and approved in accordance with Planning for Bush Fire Protection is referred to as ‘existing development’.

Existing development can be more susceptible to the impact of bush fire. Establishing a robust methodology that allows for the consistent application of risk treatments to these properties across the State is critical. When developing this methodology, it is important to recognise the limitations of implementing risk treatments for existing development. Limitations may include environmental and topographical issues surrounding interface areas which can restrict the clearing of vegetation. In addition, it is often impractical to retrofit all development with protection measures, such as building construction standards and access provisions, to provide a level of bush fire protection that is comparable to that afforded through Planning for Bush Fire Protection.

This Guide incorporates a standard process for determining the risk treatments for existing residential dwellings, Special Fire Protection Purpose (SFPP) developments and major buildings. The risk treatments formulated in accordance with the methodology are considered to be the minimum requirements. Where appropriate and practical, the application of measures that extend beyond these minimum requirements is supported by the NSW Rural Fire Service (RFS).

It is important to note that the occurrence and impact of bush fires are difficult to predict due to the nature of fire behaviour and weather conditions. As such, the implementation of risk treatments as per this Guide does not guarantee that buildings or people will survive a bush fire event.

1.1 Background Bush fire research in the last decade has identified a number of key elements in managing the impact of bush fires on communities, particularly along the bushland interface. It has highlighted the value of undertaking risk treatment strategies in interface areas in order to protect life and property from bush fire. Common risk treatment strategies discussed in recent literature is fuel management which, in NSW, generally includes the establishment of Asset Protection Zones (APZ) through mechanical or physical means and prescribed burning activities.


Research undertaken by the Bushfire CRC (2010) into house losses during the 2009 Victorian ‘Black Saturday’ bush fires indicate that in the townships of Marysville and Kinglake, up to 60% of the houses that were lost were within 10 metres of bushland (Chen & McAneney 2010). Additional research by Gibbons et al. (2012) suggests that the implementation of a fuel reduced zone up to 40 metres from houses has potential to reduce house loss by 43%. In both cases, the research suggests that buildings in close proximity (less than 40 metres) to bushland were impacted by a combination of bush fire attack mechanisms, with flame, radiant heat and embers playing a role in house loss.

Recent work undertaken by the University of Wollongong (Price & Bradstock 2013) also reinforces the concept that separation of assets from unmanaged vegetation is an essential part of reducing the risk of life and property loss from bush fire.

It is also important that the nature of ember attack is taken into account when considering the protection of existing development from bush fire. Analysis of past bush fire events indicate that embers and wind-borne debris are the most prevalent attack mechanism on houses in Australian bush fires and is responsible for over 90% of houses lost (Potter & Leonard 2010). Work in this area indicates that embers can travel significant distance (up to 700m) from bushland areas and cause damage to buildings (Chen & McAneney 2010). Therefore, whilst maintaining separation between assets and bush fire hazards is an important treatment, it must be coupled with appropriate building improvements in order to protect against embers and effectively reduce the bush fire risk.

It has been well documented that weather is an important factor that influences bush fire behaviour and intensity. Studies show that fuel treatment by prescribed burning will have negligible effects on fire suppression during Severe to Catastrophic fire weather conditions (Price & Bradstock 2012). Fuel ages of up to 5–10 years in an area may reduce the intensity of the fire but not sufficiently to increase the chance of suppression under these weather conditions. This study further supports the concept of employing a combination of risk management treatments and not placing sole reliance on fuel management, particularly prescribed burning.

In summary, the research referenced above reinforces the following principles in managing bush fire risk to communities: • Providing separation between assets and bush fire hazards is an important aspect of

reducing the risk of life and property losses from bush fire; • Ember attack can cause damage to buildings over significant distances (up to 700m)

and is responsible for a large portion of house ignitions. Combining fuel management with improved construction standards will provide increased protection against bush fires;

• Fuel management treatments alone will not always be effective during Severe to Catastrophic fire weather conditions; and

• Treatment strategies such as suppression, ignition management, preparedness, community education, planning and building improvements will assist in further reducing the bush fire risk to life and property.

The above principles have been used to provide a basis for the approach outlined in this Guide.

1.2 Dictionary and definitions Expressions defined in Section 100A and definitions within the Dictionary of the Rural Fires Act 1997 also apply to this Guide. Specific terms that are used in this Guide are defined in Section 6.


1.3 Purpose The purpose of this Guide is to outline a standard methodology for assessing and treating existing residential, SFPP development and major buildings at risk of bush fire. It has been developed to support consistent decision making when implementing bush fire risk treatments to address existing obligations required by Section 63 of the Rural Fires Act 1997. This includes treatment actions described in a Bush Fire Risk Management Plan, identified in a Community Protection Plan, or generated as a result of a Hazard Complaint.

1.4 Aim The aim of this Guide is to provide communities of NSW with a reasonable level of bush fire protection to improve life safety (including fire fighters) and to reduce the risks of impacts on property from the threat of bush fire, while taking into account existing development constraints, on-site amenity and protection of the environment.

More specifically, the objectivesi. Afford occupants of buildings with reasonable protection from exposure to a bush

fire;

are to:

ii. Provide for a defendable space to be located around occupied buildings; iii. Provide appropriate separation between a hazard and buildings which, in

combination with other measures, provides for reasonable protection against bush fire attack, having due regard to the potential for flame contact, radiant heat and embers;

iv. Provide for ongoing management and maintenance of bush fire risk treatments, including fuel loads in APZs; and

v. Promote the concept of shared responsibility for bush fire risk management between land managers, fire authorities and the community.

1.5 Scope This Guide applies to existing residential, SFPP or major building assets that have not been assessed and approved under Planning for Bush Fire Protection. Buildings that have been designed and constructed to these standards will not require additional treatment beyond the conditions of consent for the development.

1.6 Limitations Due to certain limitations, the measures contained in this document do not guarantee that loss of life, injury and/or property damage will not occur during a bush fire event. Limitations of this document include, but are not limited to, uncertainties in the following areas:

› Bush Fire Science › Fire scenarios; › Fuel loads; › Human behaviour; and › Maintenance


1.6.1 Bush Fire Science

The methodology provided for in this Guide is based on established science available at the time. It is recognised that current bush fire behaviour models and risk assessment processes contain assumptions that may limit the accuracy of results in some circumstances. Further research and development in this area, particularly in relation to the quantification of bush fire risk and treatment effectiveness, is likely to assist in the refinement of the methodology in the future.

1.6.2 Fire Scenarios It is possible that the bush fire scenario experienced on a given day may exceed those planned for in this Guide (i.e. a higher Fire Danger Index). Under these circumstances, the performance of risk treatments designed in accordance with this document may be inadequate due to increased levels of radiant heat exposure, flame contact, ember attack (including spotting distances) and wind.

1.6.3 Fuel loads

Fuel load is a measure of the amount of vegetation available to a bush fire.

In some instances, actual fuel loads in an area at a particular time may be higher than the maximum predicted within this Guide. This can result in more intense bush fire behaviour with greater potential impact on life and property.

1.6.4 Human behaviour Being involved in a bush fire can be a highly traumatic experience and the behaviour of people under considerable stress may be unpredictable. The actions they take can have a significant influence on the level of impact of a bush fire. The safety of occupants during a bush fire event is predicated on their overall health, fitness and wellbeing as well as their ability to respond in an appropriate fashion.

1.6.5 Maintenance

The protection afforded by this document is based on a suitable level of ongoing maintenance.

The best planning can be hampered by poor maintenance and housekeeping. An unprepared property is not only a risk to the building owner/occupant, but may also present an increased danger to neighbouring buildings, neighbouring residents and fire fighters.

1.7 Legislation and Policy The Rural Fires Act 1997 is the primary piece of legislation that relates to bush fire risk management in NSW. The relevant objectives of this Act include:

• (c) the protection of persons from injury or death, and property from damage, arising from fires,

• (c1) for the protection of infrastructure and environmental, economic, cultural, agricultural and community assets from damage arising from fires, and


• (d) the protection of the environment by requiring certain activities to be carried out having regard to the principles of ecologically sustainable development.

The main sections and parts of the Act that are applicable to this Guide are outlined below: • Part 3, Division 4 Preparation of Draft Bush Fire Management Plan – Outlines the

responsibilities and content for Draft Bush Fire Management Plans. Draft Bush Fire Management Plans include a Bush Fire Risk Management Plan which identifies risk treatments for an area that are designed to protect assets from bush fire. Actions identified in the Bush Fire Risk Management Plan constitute a notified step under Section 63.

• Section 63 – Requires a public authority, the owner or occupier of land to take the notified steps (if any) and any other practicable steps to prevent the occurrence of bush fires on, and to minimise the danger of the spread of a bush fire on or from their land. A public authority, or owner or occupier is liable for the costs incurred by it in performing the duty imposed by this Section.

• Section 66 – Stipulates that an owner or occupier of land can be required to carry out bush fire hazard reduction work specified in a notice.

• Section 74A-F – Sets out the legal provisions for bush fire hazard complaints throughout NSW.

Other legislation that is relevant to the implementation of bush fire protection works in NSW includes:

• Environmental Planning and Assessment Act 1979 • National Parks and Wildlife Act 1974 • Native Vegetation Act 2003 • Threatened Species Conservation Act 1995 • Protection of the Environment Operations Act 1997

Key policy and publications that are related to this Guide are outlined below. • Bush Fire Environmental Assessment Code • 10/50 Vegetation Clearing Code of Practice • Bush Fire Coordinating Committee Policy 1/2008 – Bush Fire Risk Management • Guide to making a Bush Fire Survival Plan (NSW RFS) • Guide to Developing a Bush Fire Emergency Management and Evacuation Plan

(NSW RFS) • Standards for Asset Protection Zones (NSW RFS) • Planning for Bush Fire Protection • National Construction Code • Australian Standard 3959-2009 – Construction of buildings in bushfire prone areas • Building Best Practice Guide – Upgrading of Existing Buildings (NSW RFS) • Standards for Bush Fire Hazard Reduction Works in SEPP 14 Coastal Wetlands

(NSW Department of Planning and NSW RFS)

1.8 Review of this Guide This Guide and associated tools will be subject to a review after the first 12 months from implementation and then within every five year period. Amendments may occur as new


research becomes available including expansion to account for other asset types. The review will include consultation with key stakeholders involved in the development of this document.


2 Applying This Guide This Guide sets out a standard process for assessing and determining the required risk treatments for a given type of existing development. With regard to risk treatment options, the process provides for the following two pathways:

1. Acceptable approach – see Chapter 4 2. Alternate approach – see Chapter 5

An alternate approach can only be employed where the acceptable approach cannot be achieved. The application of the alternate approach is limited to circumstances where environmental constraints restrict the implementation of treatment works. In most cases, if a Hazard Reduction Certificate can be issued for the proposed works which meet the requirements of the Bush Fire Environmental Assessment Code the APZ works are considered achievable.

The following supporting documents provide more detailed guidance on the implementation of risk treatments and should be read in conjunction with this Guide.

• Guide to Developing a Bush Fire Emergency Management and Evacuation Plan (NSW RFS)

• Guide to making a Bush Fire Survival Plan (NSW RFS) • Standards for Asset Protection Zones (NSW RFS) • Building Best Practice Guide – Upgrading of Existing Buildings (NSW RFS)

Figure 1 provides an overview of the process for assessing existing developments and identifying the applicable treatment requirements.


Figure 1. Guide Overview

Classify development type

Existing Residential Development

Special Fire Protection Purpose Major Buildings

Undertake site assessment;Identify vegetation type and effective slope

Determine the required risk treatments

Can the treatments be achieved

Implement Acceptable Approach for

development type YES Go to Alternate Approach

for development typeNO

See Figure 5 & 6Alternate Approach

for Residential Development

See Figure 7 & 8Alternate Approach

for SFPP

See Figure 9 Alternate

Approach for Major Buildings


2.1 Property Protection Level Matrix Figure 2 and 3 provides a visual representation of how the bush fire risk treatments detailed in the acceptable and alternate approaches improve level of property protection for existing residential and SFPP assets. The first step is to reduce the levels of radiant heat impacting the asset by applying the required APZ. For those properties where the proposed APZ distances can be achieved the resident / management is provided with information they can use to better prepare their property (i.e. Awareness Treatments). For those properties where the APZs cannot be achieved the resultant radiant heat is used to determine the additional measures required (i.e. Targeted or Comprehensive Treatments). The matrix below outlines how to provide a minimum level of protection using the methodology contained in this Guide.

Figure 2. Property Protection Level Matrix for Existing Residential Development

Property & Resident Improvement Treatments Hazard Rating Following Implementation of APZ

No Additional Treatments Awareness Targeted Comprehensive

Very High / Extreme (>29 kW/m²) Unacceptable Unacceptable Unacceptable Minimum High (19-29 kW/m²) Unacceptable Unacceptable Minimum Good Moderate (12.5-19 kW/m²) Unacceptable Minimum Good Very Good Low (<12.5 kW/m²) Minimum Good Very Good Very Good

Awareness Treatments Resident is provided with documents and materials regarding their property protection level, their responsibilities and general advice on actions they can undertake to further reduce their risk.

Targeted Treatments

In addition to the Awareness Treatments, the resident is provided with a tailored engagement activity (e.g. a property inspection) and guidance on how to complete their Bush Fire Survival Plan. The APZ for the dwelling is to be managed entirely as an Inner Protection Area (see Figure 5).

Comprehensive Treatments Involves the application of awareness and targeted measures as well as specified measures as identified in the alternate approach (see Figure 6).


Figure 3. Property Protection Level Matrix for On Site Refuge Buildings of an Existing SFPP Development

Property & Management Improvement Treatments Hazard Rating Following Implementation of APZ

No Additional Treatments Awareness Targeted Comprehensive

Very High / Extreme (>19 kW/m²) Unacceptable Unacceptable Unacceptable Minimum High (10-19 kW/m²) Unacceptable Unacceptable Minimum Good Moderate (<10 kW/m²) Unacceptable Minimum Good Very Good

Awareness Treatments Management is provided with documents and materials regarding their property protection level, their responsibilities and general advice on actions they can undertake to further reduce their risk.

Targeted Treatments

In addition to the Awareness Treatments, the management is provided with a tailored engagement activity (e.g. a property inspection) and guidance on emergency management of the facility. The APZ for the dwelling is to be managed entirely as an Inner Protection Area (see Figure 7).

Comprehensive Treatments Involves the application of Awareness and Targeted Treatments as well as specified measures as identified in the alternate approach (see Figure 8).


3 Assessing Existing Development The two key components in assessing existing development at risk of bush fire are to classify the development type and undertake a site assessment.

3.1 Classify Development Type The existing development should be classified into one of the following development types:

1. Residential Development – includes any habitable building (see Note 1); 2. SFPP Development - as defined in Section 100B of the Rural Fires Act 1997; or 3. Major Building - farm sheds, industrial buildings, commercial buildings, community

buildings and heritage listed structures (see Note 2).

Note 1 - Enclosed ancillary structures made from combustible materials (i.e. garages and studios with a floor area of greater than 20sqm) on residential properties which are within six metres of the primary dwelling are to be considered as part of the residence for the purposes of establishing the APZ.

Note 2 – Provisions for telecommunication towers are outlined in the NSW RFS Practice Note 1/11.

3.2 Undertake Site Assessment The site assessment for determining the risk treatment requirements is outlined below. Where more than one side is exposed to a hazard, each elevation should be assessed.

1. Determine the predominant vegetation – The predominant vegetation class is to be classified in accordance with Ocean Shores to Desert Dunes (Keith 2004). Heath vegetation classes are to be further categorised as either short (less than 2 metres in height) or tall heath (greater than 2 metres in height). The vegetation that presents the greatest hazard for the asset is considered to be the predominant vegetation. Vegetation that meets the definition of an ‘Exclusion’ as per the NSW RFS document Guide for Bush Fire Prone Land Mapping (v5b November 2015) is considered to be low threat vegetation and does not require specific treatments under this Guide. There may be instances where invasive weed species (native or introduced) and/or land management practices have altered the structure, function and composition of a vegetation community. In these circumstances, vegetation can be reclassified into a class which best reflects the structure, function and composition as well as the potential bush fire behaviour of the community.

2. Determine the effective slope – The effective slope is the gradient of the land beneath the hazard that will most significantly influence bush fire behaviour for the asset (see Figure 4 below). Effective slope is to be calculated in degrees.


Figure 4. Determining effective slope

3. Determine if the short fire run methodology applies. Refer to Short Fire Run

Practice Note. 2016

Following an assessment of the site and classification of the development type, the APZ size can be determined by either referring to the tables in the Appendices or entering the inputs into the NSW RFS Existing Development Treatment Calculator. The APZ distances should be measured on the horizontal plane from the external wall of the building. The definition of the external wall is provided in Section 6.


4 Acceptable Approach for Risk Treatments 4.1 Existing Residential Development

The acceptable approach for treating existing residential development at risk of bush fire is outlined below.

1. APZ distances are in accordance with Appendix 1 or the NSW RFS Existing Development Treatment Calculator.

2. APZs to be implemented and maintained in accordance with the Standards for Asset Protection Zones (NSW RFS).

3. Residents are informed of their responsibility to: – Maintain their APZ(s) on an ongoing basis; – Upgrade their house as per Building Best Practice Guide – Upgrading of Existing

Buildings (NSW RFS); and – Prepare a Bush Fire Survival Plan.

Rationale The APZ distances outlined in Appendix 1 are based on a radiant heat of less than 19 kW/m² and a Forest Fire Danger Index (FFDI) of 50.

A radiant heat target of less than 19 kW/m² is based on information provided in Table A3.4.2 of Planning for Bush Fire Protection 2006 (page 3 of Addendum Appendix 3) regarding the impact of different levels of radiant heat on building elements. This table states that the integrity of buildings will be threatened when exposed to radiant heat loads greater than 19 kW/m². Whilst some building elements may still be affected at radiant heat load below 19 kW/m², the implementation of building upgrades can be applied to reduce the risk of building ignition at these levels. These building upgrades are considered to be a reasonable and practical measure for an asset owner to undertake. The need to undertake building upgrades to complement the APZs promotes the concept of shared responsibility in bush fire management.

A FFDI of 50 aligns with a Severe Fire Danger Rating and is the point at which a range of other risk treatments are activated. This includes:

• The issuing of fire weather warnings to the community and the declaration of Total Fire Bans;

• Community advice is disseminated through the various media outlets on the heightened risk of bush fires;

• The Bush Fire Survival Plan provides specific messages to the community on actions to take to survive a bush fire; and

• Level 1 Operational Readiness is triggered for NSW RFS state, regional offices and districts.

Given the alignment of FFDI 50 (i.e. adopting an FFDI of 50) with fire weather warnings, existing community messaging and operational triggers, it was considered to be a most suitable benchmark to adopt for existing residential development.

The FFDI 50 and 19 kW/m² benchmarks operate on the theoretical premise that the APZs and building upgrades would provide bush fire protection to the dwelling up to a FFDI of 50. However, residents will still need to make a decision on the appropriate actions to take prior to and during a bush fire based on their individual circumstances as per their Bush Fire Survival Plan. The APZs and building upgrades provided for by the acceptable approach will provide a reduction in radiant heat and a defendable space which will enhance the ability of


residents and fire fighters to implement active protection measures under all fire weather scenarios.

4.2 Existing Special Fire Protection Purpose Development (SFPP) The acceptable approach for treating existing SFPP Development at risk of bush fire is outlined below.

1. An Emergency Management and Evacuation Plan are prepared for the SFPP development as per the NSW RFS Guide.

2. APZ distances for the *nominated on-site refuge are in accordance with Appendix 2. 3. APZ distances for other occupied buildings (i.e. classrooms, administration buildings,

halls, gyms) are in accordance with Appendix 1. 4. APZs to be implemented and maintained in accordance with the Standards for Asset

Protection Zones (NSW RFS). 5. Managers of the SFPP are informed of their responsibility to;

– Maintain their APZ(s) on an ongoing basis, and – Upgrade buildings as per Building Best Practice Guide – Upgrading of Existing

Buildings, 2011 (NSW RFS).

*The nominated on-site refuge is the building or part of a building that has been identified as the shelter option in the Emergency Management and Evacuation Plan.

Rationale The development of a Bush Fire Emergency Management and Evacuation Plan in accordance with the NSW RFS standard for existing SFPP developments will be the first step in providing protection to life within the facility. This Bush Fire Emergency Management and Evacuation Plan will need to identify the most suitable on-site refuge.

The APZ distances outlined in Appendix 2 seek to achieve a radiant heat target of less than 10 kW/m², coupled with a design FFDI of 100 for on-site refuge buildings.

The focus of the bush fire risk treatments for an on-site refuge is life safety. This is due to the vulnerable nature of occupants and the limitations associated with their relocation during a bush fire event. Planning for Bush Fire Protection 2006 establishes a robust position for the protection of new SFPP development that is also based on life safety of vulnerable occupants. It designates a radiant heat target of less than 10 kW/m² for these types of developments which has been adopted for the purposes of an on-site refuge for existing SFPPs.

The design FFDI 100 is the point at which a Catastrophic FDR is activated. This FFDI combined with a radiant heat load of less than 10 kW/m² ensures that on-site refuges remain as viable shelter options up to a Catastrophic FDR.

Assets that are not designated as an on-site refuge within an existing SFPP development are not considered to have the same life safety requirements under this Guide. Therefore, APZs that are commensurate with existing residential development are deemed appropriate for other occupied buildings within an existing SFPP.

4.3 Existing Major Buildings The acceptable approach for treating existing Major Buildings at risk of bush fire is outlined below.

1. APZ distances are in accordance with Appendix 3.


2. APZs to be implemented and maintained in accordance with the Standards for Asset Protection Zones (NSW RFS).

3. Asset owners are informed of their responsibility to; – Maintain their APZ(s) on an ongoing basis, – Upgrade their building as per Building Best Practice Guide – Upgrading of

Existing Buildings, (NSW RFS), and – Prepare an Emergency Management and Evacuation Plan.

Rationale The APZ distances outlined in Appendix 3 are based on a radiant heat of less than 29 kW/m² and a FFDI of 50. This aims to keep the asset out of the flame zone and provide a defendable space which facilitates fire fighting operations and hazard reduction activities.


5 Alternate Approach for Risk Treatments An alternate approach can be employed where the acceptable approach offered for the site cannot be achieved. The application of the alternate approach is limited to circumstances where environmental constraints restrict the implementation of treatment works. In most cases, if a Hazard Reduction Certificate can be issued for the proposed works which meet the requirements of the Bush Fire Environmental Assessment Code the APZ works are considered achievable.

The aim of the alternate approach is to provide additional risk treatments that will assist in offsetting the lack of separation and the higher levels of radiant heat that would be experienced by the asset. As outlined in Section 1.6.1, the effectiveness of the additional treatments associated with the alternate approaches is unable to be quantified at this stage.

5.1 Existing Residential Development There are two alternate approaches that can be used to treat existing residential developments. In deciding which alternate approach applies, determine the size of the achievable APZ and calculate the resultant radiant heat on the asset.

Based on this calculated radiant heat, the property should then be classified into either 19-29kw/m2 approach or greater than 29kw/m2

For assets that fall into the 19-29kw/m

approach. 2

1. The whole APZ should be maintained as an Inner Protection Area.

category the following Targeted Treatments are required;

2. Provide the resident with a targeted community engagement activity, such as a property inspection, to provide specific and tailored advice on:

– undertaking upgrades to the dwelling to protect against ember attack; – preparing their property to reduce the impacts of bush fire; and – the preparation of their Bush Fire Survival Plan.

Figure 5 outlines the 19-29kw/m2

For assets that fall into the greater than 29kw/m

approach. 2


category the following Comprehensive Treatments are required.

2. Provide the resident with a targeted community engagement activity, such as a property inspection to provide specific and tailored advice on:

– undertaking upgrades to the dwelling to protect against ember attack; – preparing their property to reduce the impacts of bush fire; and – the preparation of their Bush Fire Survival Plan.

3. A prescribed burn proposal is to be developed for the area and submitted to the local Bush Fire Management Committee so that it can be assessed along with other proposals for consideration as an inclusion in the annual works or contingency plan.

4. Factors surrounding the property such as road access, fire trail access, and vegetation under power lines and condition of APZs adjacent to the property are inspected to see if any improvements can be made.

Figure 6 outlines the greater than 29kw/m2

approach.


Figure 5. Alternate Approach for Existing Residential Development 19-29kw/m2

Apply Additional Vegetation ManagementAll the APZ needs to be managed as an Inner Protection Area

Apply Targeted TreatmentsUndertake a Tailored Community Engagement Activity which may include;

• A Property Inspection • Bush Fire Survival Plan Preparation Guidance

Apply Achievable APZ

Determine the radiant heat based on the achievable Asset Protection Zone

What is the radiant heat class?

Go to Figure 6.Alternate Approach

for Residential Development

>29kw

19-29kw

>29kw


Figure 6. Alternate Approach for Existing Residential Development Greater Than 29kw/m


Apply Targeted TreatmentsUndertake a targeted Community Engagement Activity which may include;

• Property Inspection • Bush Fire Survival Plan Preparation Guidance

Apply Additional Vegetation ManagementAll APZ needs to be managed as an Inner Protection Area

Identify Strategic Hazard ReductionDevelop a Prescribed Burn Proposal and submit to the BFMC for consideration

as an inclusion in the annual works or contingency program

Apply Comprehensive TreatmentsUndertake an additional assessment of the property and surrounds with

consideration for improvements that could be made to ;• Adjacent Property Preparedness

• Ignition Management• Fire Trail Maintenance

• Property AccessApply additional treatments where applicable.

2


5.2 Existing Special Fire Protection Purpose (SFPP) Development There are two alternate approaches that can be used to treat existing SFPP developments. In deciding which alternate approach applies, determine the size of the achievable APZ and calculate the resultant radiant heat on the asset.

Based on the calculated radiant heat, the SFPP should then be classified into either 10-19kw/m2 or greater than 19kw/m2

For assets that fall into the 10-19kw/m

. 2

1. The whole APZ should be maintained as an Inner Protection Area; and

category, the following Targeted Treatments are required;

2. Provide the property manager with a targeted community engagement activity, such as a property inspection, to give specific and tailored advice on:

– undertaking upgrades to the buildings to protect against ember attack, – preparing their property to reduce the impacts of bush fire, and – the preparation of their Emergency Management and Evacuation Plan.

Figure 7 outlines the 10-19kw/m2

For properties which have a resultant radiant heat of greater than 19kw/m

approach 2

1. The whole APZ should be maintained as an Inner Protection Area;

the following Comprehensive Treatments are required;

2. Provide the property manager with a targeted community engagement activity, such as a property inspection, to give specific and tailored advice on:

– undertaking upgrades to the buildings to protect against ember attack, – preparing their property to reduce the impacts of bush fire, and – the preparation of their Emergency Management and Evacuation Plan.

3. The responsible fire agency should prepare (or review) a Pre-Incident Plan for the facility;

4. A prescribed burn proposal is to be developed for the area and submitted to the local Bush Fire Management Committee so that it can be assessed along with other proposals for consideration as an inclusion in the annual works or contingency plan; and

5. Factors surrounding the facility such as road access, fire trail access, vegetation under power lines and condition of APZs adjacent to the property are inspected to see if any improvements can be made.

Figure 8 outlines the greater than 19kw/m2

approach.


Figure 7. Alternate Approach for Existing SFPP Development 10-19kw/m

2

Apply Additional Vegetation ManagementAll the APZ needs to be managed as an Inner protection Area

Apply Targeted Treatments Undertake a targeted Community Engagement Activity which may include;

• A Property Inspection• Emergency Management and Evacuation Guidance

• Bush Fire Survival Plan Preparation Guidance where applicable • Advice on Emergency Management Triggers


Determine radiant heat based on

achievable APZ

What is the radiant heat

class?

Go to Figure 8 Alternate

Approach for SFPP

Development >19kw

10-19kw

>19kw

.


Figure 8. Alternate Approach for Existing SFPP Development Greater Than 19kw/m

2


Apply Targeted TreatmentsUndertake a targeted Community Engagement Activity which may include;

• A Property Inspection • Emergency Management and Evacuation Guidance

• Bush Fire Survival Plan Preparation Guidance where applicable • Advice on Emergency Management Triggers

Apply Additional Vegetation ManagementAll APZ needs to be managed as an Inner Protection Area

Identify Strategic Hazard ReductionDevelop Prescribed Burn Proposal and submit to the BFMC for consideration as

an inclusion in the annual works or contingency program

Enhance Initial Response CapabilityReview or develop PIP for SFPP

Apply Comprehensive TreatmentsUndertake an additional assessment of the property and surrounds with

consideration for improvements that could be made to ;• Adjacent Property Preparedness

• Ignition Management• Fire Trail Maintenance

• Property AccessImplement additional treatments where applicable


5.3 Existing Major Buildings For those existing major buildings where the specified APZ cannot be achieved the following additional treatment is required:


Figure 9 outlines the alternate approach for existing major buildings.

Figure 9. Alternate Approach for Existing Major Buildings


Apply Additional Vegetation Management

All APZ needs to be managed as an Inner Protection Area


6 Dictionary

Asset Protection Zone (APZ) - an area between a bush fire hazard and buildings, which is more intensively and routinely managed to minimise fuel loads and reduce the potential radiant heat levels, flame contact, ember and smoke attack on life and property. In a forest vegetation the APZ can be made up of a Inner Protection Area and a Outer Protection Area

Defendable Space - an area adjoining the asset, managed to reduce combustible elements and free constructed impediments that provides a safe working environment in which active fire fighting can be undertaken to defend the structure, before and after the passage of bush fire (Planning for Bush Fire Protection 2006).

Enclosed Ancillary Structures - include garages and studios with a floor area of greater than 20sqm. It does not include structures that are made of non-combustible material.

Existing Development – a building/structure or part of a building/structure that has not that has not been assessed and approved under Planning for Bush Fire Protection designed and constructed in accordance with Planning for Bush Fire Protection.

External Wall - external walls of a building include permanent fixed structures such as decks, verandas, pergolas and garages that are attached to the building. Decks and verandas are elevated platforms (either enclosed or unenclosed). External walls do not include constructions such as paved or concreted areas. With respect to farm sheds, external walls refer to the external walls of a farm shed or the line between two support posts in the event that the farm shed does not have a wall.

Note: External wall excludes exempt development such as decks or verandas which have been constructed according to the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008. This is because these structures are required to be made of non-combustible material. It also excludes the alterations / additions to existing buildings that have been designed and constructed in accordance with Planning for Bush Fire Protection. Heritage Structure means a building or structure which is described in Schedule 5 of the Standard Instrument - Principal Local Environmental Plan or listed on the NSW State Heritage Register.

http://www.environment.nsw.gov.au/heritageapp/heritagesearch.aspx

Inner Protection Area – The Part of the Asset Protection Zone closest to the asset which has highly reduced fuel levels that can minimise the impact of direct flame contact and can act as a defendable space. For further details see NSW RFS document Standards for Asset Protection Zones

Maintenance - work undertaken to ensure a management zone, structure or feature retains its intended function, and does not include extending, upgrading or realignment for a higher level of use. Ongoing maintenance for bush fire hazard reduction may be recorded in a bush fire risk management plan or other associated plan of management or maintenance roster.

Native Vegetation - any indigenous vegetation as defined in Section 6 of the Native Vegetation Act 2003.

Noxious Weeds - plants declared as noxious weeds in the schedules of a Noxious Weeds (Weed Control) Order pursuant to the Noxious Weeds Act 1993.

Occupied Buildings - buildings within a Special Fire Protection Purpose that are used for extended periods during the operation of the facility. They include classrooms, administration buildings, halls, gyms, cafeterias and the like. Ancillary buildings such as external restrooms or storerooms are not considered to be occupied buildings for the purpose of this Guide.

http://www.environment.nsw.gov.au/heritageapp/heritagesearch.aspx�


Outer Protection Area – The part of the Asset Protection Zone closer to the hazard, where fuel can be managed at a moderate level in order to decrease the intensity of an approaching fire and restrict the pathway to crown fuels. For further details see NSW RFS document Standards for Asset Protection Zones

Planning for Bush Fire Protection (PBP) - the primary document incorporating bush fire protection measures for new developments occurring within bush fire prone lands.

Short Fire Run Methodology – the methodology as described in draft NSW RFS document Short Fire Run – A Risk Perspective for the Bushland Interface 2016.

Special Fire Protection Purpose (SFPP) - as defined in Section 100B(6) of the Rural Fires Act 1997.

Vegetation Classes - groups of vegetation defined mainly by overall floristic similarities (i.e. shared species) although they may also share structural and habitat characteristics (Keith 2004 p. 22).

Vegetation Communities - assemblages of plant species that live together, generally at the same time. They are the most detailed and homogeneous units in the classification hierarchy (Keith 2004 p. 22).

Vegetation Formations - broad vegetation groups distinguished by structural and physiognomic features (Keith 2004 p. 22).


7 References Blanchi R, Lucas C, Leonard J & Finkele K. (2010), Meteorological conditions and wildfire-related house loss in Australia. International Journal of Wildland Fire 19, 914–926.

Bradstock R, Cary G, Davies I, Lindenmayer D, Price O & Williams R. (2012), Wildfires, fuel treatment and risk mitigation in Australian eucalypt forests: Insights from landscape-scale simulation. Journal of Environmental Management 105, 66-75.

Catchpole E, Alexander M & Gill A. (1992). Elliptical-fire perimeter- and area-intensity distributions, Canadian Journal of Forest Research, 22 (7), 157-162.

Chen K & McAneney J (2010) Bushfire Penetration into Urban Areas in Australia: A Spatial Analysis, Report to Bushfires CRC

Cheney P & Sullivan A (1997) Grassfires - fuel, weather and fire behaviour. CSIRO Publishing, Melbourne, Australia.

Gibbons P, van Bommel L, Gill AM, Cary GJ, Driscoll DA, et al. (2012), Land Management Practices Associated with House Loss in Wildfires. PLoS ONE 7(1) e29212

Gould J, McCaw W & Cheney N. (2004), Project Vesta: findings, extension and validation for south-eastern Australian eucalypt forests, In Proceedings of Bushfire 2004 Conference, Adelaide SA, 25-28 May 2004 Department of Environment and Heritage, Adelaide,1–8.

Keith, D (2004) Ocean Shores to Desert Dunes: the native vegetation of New South Wales and the ACT. DIPNR (NSW) and NSW NPWS (OEH). Department of Environment and Conservation (NSW)

Luke R & McArthur A (1978), Bushfires in Australia, CSIRO Canberra.

McCarthy G, Tolhurst K & Chatto K (1999). Overall Fuel Hazard Guide 3rd

NSW Rural Fire Service (2006) Planning for Bush Fire Protection, Sydney NSW

Edition, Department of Sustainability and Environment, Melbourne 2003

Potter M & Leonard J (2010), Spray system design for ember attack – Research findings and discussion paper. Report to Bushfire CRC

Price O & Bradstock R (2012), The efficacy of fuel treatment in mitigating property loss during wildfires: insights from analysis of the severity of the catastrophic fires in 2009 in Victoria, Australia, Journal of Environmental Management 113, 146-157.

Price O & Bradstock R (2013b), Landscape Scale Influences of Forest Area and Housing Density on House Loss in the 2009 Victorian Bush Fires. PLoS ONE 8(8): e73421

Standards Australia (2009), Australian Standard 3959-2009 – Construction of buildings in bushfire prone areas, SAI Global Ltd., Sydney

Tan, Z, Midgley, S, & Douglas, G (2006), A Computerized Model for Bush Fire Attack Assessment and its Applications in Bush Fire Protection Planning, http://mssanz.org.au/modsim05/papers/tan_z.pdf

Tolhurst K (2010), Fire Behaviour Analyst, Intermediate Level, University of Melbourne.

Watson, P (2011) Fuel Load Dynamics in NSW Vegetation Part 1: forests and grassy woodlands. University of Wollongong.

http://mssanz.org.au/modsim05/papers/tan_z.pdf�


Appendix 1 – APZ Tables for Existing Residential Development

The APZ distances specified below apply to existing residential development in accordance with the acceptable approach outlined in Section 4.1. The distances are also relevant to other occupied buildings associated with existing SFPP developments as per the acceptable approach identified in Section 4.2. The APZ calculations are based on the following standardised inputs:

• Radiant heat load target of 19 kW/m² (see Section 4.1); • FFDI of 50 (see Section 4.1); • Maximum overall fuel loads for the vegetation community. Surface available fuel loads consists

of surface and elevated fuel loads combined; • Flame width of 100m (as per Planning for Bush Fire Protection 2006); • Flame temperature of 1090K (as per Planning for Bush Fire Protection 2006); • Site (APZ) slope of 0 degrees; and • Elevation of receiver of two metres.

Where an APZ of greater than or equal to 15 metres is required for Wet Sclerophyll and Dry Sclerophyll Forest classes, an Outer Protection Area of up to 30% of the total APZ width is permitted. In addition to the implementation of an APZ between the building and the bush fire hazard, a defendable space of up to 10m is also required on the non hazard sides of the asset. This defendable space should be managed as an Inner Protection Area.

For some vegetation types (e.g. Pilliga Outwash Dry Sclerophyll Forest), the low fuel loads result in a minimum APZ distance that is less than 10 metres. In these circumstances, a minimum APZ of 10 metres will be specified to provide a defendable space that facilitates fire fighting operations and hazard reduction activities. Wet Sc le roph yll Fo res ts (Gras s y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Southern Tableland WSF Overall Fuel Load: 25.05 t/ha

18 22 27 34 43

Northern Hinterland WSF Overall Fuel Load: 26.55 t/ha

18 22 28 34 43

Southern Lowland WSF Overall Fuel Load: 26.4 t/ha

18 22 27 34 43

Northern Tableland WSF Overall Fuel Load: 25.76 t/ha

18 22 27 34 43

Montane WSF Overall Fuel Load: 31.3 t/ha

22 27 33 42 51

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels)


Wet Sc le roph yll Fo res ts (s hrubb y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

North Coast WSF Overall Fuel Load: 28.99 t/ha

19 24 30 37 46

Southern Escarpment WSF Overall Fuel Load: 29.05 t/ha

19 24 30 37 46

South Coast WSF Overall Fuel Load: 28.67 t/ha

19 24 30 37 46

Northern Escarpment WSF Overall Fuel Load: 29.3 t/ha

19 24 30 37 46

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Dry Scleroph yll Fores ts (Shrub / Gras s y)

EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Pillaga Outwash DSF Overall Fuel Load: 9.02 t/ha

10 10 12 15 17

Clarence DSF Overall Fuel Load: 19.59 t/ha

13 17 21 26 33

Northern Gorge DSF Overall Fuel Load: 19.9 t/ha

14 17 21 26 33

Hunter-Macleay DSF Overall Fuel Load: 19.3 t/ha

14 17 21 26 33

Cumberland DSF Overall Fuel Load: 19.48 t/ha

13 17 21 26 33

Central Gorge DSF Overall Fuel Load: 19.9 t/ha

14 17 21 26 33

Southern Hinterland DSF Overall Fuel Load: 19.96 t/ha

14 17 21 26 33

New England DSF Overall Fuel Load: 19.61 t/ha

14 17 21 26 33

Upper Riverina Overall Fuel Load: 19.54 t/ha

13 17 21 26 33

North-West Slopes DSF Overall Fuel Load: 19.23 t/ha

13 17 21 26 33



Dry Scleroph yll Fores ts (Shrubb y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Sydney Coastal DSF Overall Fuel Load: 24.3 t/ha

18 23 28 35 44

Sydney Hinterland DSF Overall Fuel Load: 24.36 t/ha

18 23 28 35 44

Sydney Montane DSF Overall Fuel Load: 24.38 t/ha

18 23 28 35 44

North Coast DSF Overall Fuel Load: 24.87 t/ha

18 23 28 35 44

Northern Escarpment DSF Overall Fuel Load: 24.67 t/ha

18 23 28 35 44

Coastal Dune DSF Overall Fuel Load: 25.8 t/ha

18 22 28 35 43

South Coast Sands DSF Overall Fuel Load: 25.7 t/ha

18 22 28 35 43

Sydney Sand Flats DSF Overall Fuel Load: 25.0 t/ha

18 22 28 35 43

Southern Tableland DSF Overall Fuel Load: 26.67 t/ha

19 24 30 37 46

Northern Tableland DSF Overall Fuel Load: 27 t/ha

19 24 30 37 46

Southern Wattle DSF Overall Fuel Load: 22.5 t/ha

16 19 24 30 38

Western Slopes DSF Overall Fuel Load: 16.93 t/ha

14 17 21 27 34

South East DSF Overall Fuel Load: 22.5 t/ha

16 19 24 30 38

Yetman DSF

Overall Fuel Load: 16.93 t/ha

14 17 21 27 34



Gras s y Woodland EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Coastal Valley Grassy Woodlands Overall Fuel Load: 14.03 t/ha

10 13 16 20 26

Table Clay Woodlands Overall Fuel Load: 14.55 t/ha

11 13 16 21 27

Subalpine Woodlands Overall Fuel Load: 22.65 t/ha

16 20 25 32 40

New England Woodlands Overall Fuel Load: 15.35 t/ha

11 13 17 21 27

Southern Tableland Woodlands Overall Fuel Load: 14.75 t/ha

11 13 17 21 27

Western Slope Woodlands Overall Fuel Load: 14.4 t/ha

10 13 16 21 27

Floodplain Transition Woodlands Overall Fuel Load: 14.7 t/ha

11 13 17 21 27

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Rainfores t (All Cla s s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Rainforest Overall Fuel Load: 11.6 t/ha

10 12 15 20 25

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Fores ted Wetland s (All Clas s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Forested Wetlands **Overall Fuel Load: 20 t/ha

14 17 22 28 35

(Fuel loads derived from Planning for Bush Fire Protection 2006)

*Forested wetlands on slopes greater than five degrees are unlikely to occur. Therefore, there should be no conflict between the APZ distances and Standards for Bush Fire Hazard Reduction Works in SEPP 14 Coastal Wetlands.

**Research to be undertaken by University of Wollongong on fuel accumulation within Forested Wetlands. Fuel loads used in the calculation of APZ distances may be subject to change pending the outcome of this research.


Tall Heath (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Tall Heath **Overall Fuel Load: 25 t/ha

16 18 20 23 26


*Wind speed used for Radiant Heat Modelling for Heathlands has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide. Heathlands have not been broken down into the Keith sub classifications. Heathlands are divided into Tall Heath (greater than two metres in height) and Short Heath (less than two metres in height) which is consistent with the methodology in Planning for Bush Fire Protection 2006.

**Research to be undertaken by University of Wollongong on fuel accumulation within Heaths. Fuel loads used in the calculation of APZ distances may be subject to change pending the outcome of this research.

Short Heath (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Short Heath **Overall Fuel Load: 15 t/ha

11 13 14 17 19




Alpin e Complex (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Alpine Complex Overall Fuel Load: 17t/ha

12 13 15 17 20

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Short Heath used) *Wind speed used for Radiant Heat Modelling for Alpine Complex has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide. Fres hwater Wetlands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Freshwater Wetlands Overall Fuel Load: 15t/ha

11 13 14 17 19

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Shrubland chenopod used) *Wind speed used for Radiant Heat Modelling for Freshwater Wetlands has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide.


Arid Sh rub lands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Arid Shrublands Overall Fuel Load: 9t/ha

10 10 12 14 16

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Shrubland chenopod used)

*Wind speed used for Radiant Heat Modelling for Arid Shrublands has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide.

Semi-a rid Woodlands (All Clas s es )


Upslope/Flat >0-5 >5-10 >10-15 >15-20

Semi-arid Woodlands Overall Fuel Load: 18t/ha

10 10 11 13 16

(Fuel loads derived from Planning for Bush Fire Protection 2006) Pine Plan ta tions EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Pine Plantations Overall Fuel Load: 25t/ha

18 22 27 34 43

(Fuel loads derived from Planning for Bush Fire Protection 2006) Gras s lands (All Cla s s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Grasslands 10 10 10 10 10



Appendix 2 – APZ Tables for SFPP Development

The APZ distances specified below apply to nominated on-site refuge buildings for an existing SFPP development as per the acceptable approach outlined in Section 4.2. The APZ calculations are based on the following standardised inputs:

• Radiant heat load target of 10 kW/m² (see Section 4.2); • FFDI of 100 and GFDI 130 (see Section 4.2); • Maximum overall fuel loads for the vegetation community. Surface available fuel loads consists

of surface and elevated fuel loads combined; • Flame width of 100m (as per Planning for Bush Fire Protection 2006); • Flame temperature of 1200K (as per Planning for Bush Fire Protection 2006); and • Site (APZ) slope of 0 degrees • Elevation of receiver of two metres

For Wet Sclerophyll and Dry Sclerophyll Forest classes, an Outer Protection Area of up to 30% of the total APZ width is permitted.

In addition to the implementation of an APZ between the building and the bush fire hazard, a defendable space of up to 10m is required on the non hazard sides of the asset. This defendable space should be managed as an Inner Protection Area. Wet Sc le roph yll Fo res ts (Gras s y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


60 72 86 100 100


61 72 86 100 100


61 72 86 100 100


60 72 86 100 100


70 84 99 100 100




Upslope/Flat >0-5 >5-10 >10-15 >15-20


64 76 91 100 100


60 71 85 100 100


64 76 91 100 100


64 77 91 100 100



Upslope/Flat >0-5 >5-10 >10-15 >15-20


29 36 45 56 68


48 59 71 85 100


48 59 71 85 100


48 58 71 85 100


48 59 71 85 100


48 59 71 85 100


49 59 71 85 100


49 59 71 85 100


48 59 71 85 100


48 58 70 85 100



Dry Scleroph yll Fores ts (Shrubb y)


Upslope/Flat >0-5 >5-10 >10-15 >15-20


62 74 89 100 100


62 74 89 100 100


62 74 89 100 100


62 74 89 100 100


62 74 89 100 100


61 73 87 100 100


61 73 87 100 100


61 73 87 100 100


64 77 92 100 100


65 77 92 100 100


55 66 79 94 100


50 60 73 87 100


55 66 79 94 100

Yetman DSF


50 60 73 87 100




Upslope/Flat >0-5 >5-10 >10-15 >15-20


38 47 57 70 84


40 49 59 72 86


56 68 81 97 100


41 49 59 72 87


40 49 59 72 86


40 49 59 72 86


40 49 59 72 86

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Rainfores t EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


37 46 57 69 84

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Fores ted Wetland s (All Clas s es )


Upslope/Flat >0-5 >5-10 >10-15 >15-20


50 61 73 88 100





Upslope/Flat >0-5 >5-10 >10-15 >15-20


44 49 55 60 67


* Heathlands have not been broken down into the Keith sub classifications. Heathlands are divided into Tall Heath (greater than two metres in height) and Short Heath (less than two metres in height) which is consistent with the methodology in Planning for Bush Fire Protection 2006.



Upslope/Flat >0-5 >5-10 >10-15 >15-20


33 37 42 46 52


* Heathlands have not been broken down into the Keith sub classifications. Heathlands are divided into Tall Heath (greater than two metres in height) and Short Heath (less than two metres in height) which is consistent with the methodology in Planning for Bush Fire Protection 2006.



Upslope/Flat >0-5 >5-10 >10-15 >15-20

Alpine Complex Overall Fuel Load: 17t/ha

34 39 43 48 54

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Short Heath used) Fres hwater Wetlands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Freshwater Wetlands Overall Fuel Load: 15t/ha

33 38 42 46 52

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Shrubland chenopod used) Arid Sh rub lands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


27 31 35 39 44





Upslope/Flat >0-5 >5-10 >10-15 >15-20


27 33 40 48 58


Pine Plan ta tions EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


60 72 86 100 100

(Fuel loads derived from Planning for Bush Fire Protection 2006) Gras s lands (All Cla s s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Grassland Overall Fuel Load: 6t/ha

36 40 46 51 57



Appendix 3 – APZ Tables for Major Buildings

The APZ distances specified below apply to major buildings in accordance with the acceptable approach outlined in Section 4.3. The APZ calculations are based on the following standardised inputs:

• Radiant heat load target of 29 kW/m² (see Section 4.3); • FFDI of 50 (see Section 4.3); • Maximum overall fuel loads for the vegetation community. Surface available fuel loads consists

of surface and elevated fuel loads combined; • Flame width of 100m (As per Planning for Bush Fire Protection 2006); • Flame temperature of 1090K (As per Planning for Bush Fire Protection 2006); • Site (APZ) slope of 0 degrees; and • Elevation of receiver of 2 metres.

Where an APZ of greater than or equal to 15 metres is required for Wet Sclerophyll and Dry Sclerophyll Forest formations, an Outer Protection Area of up to 30% of the total APZ width is permitted. In addition to the implementation of an APZ between the building and the bush fire hazard, a defendable space of up to 10m is required on the non hazard sides of the asset. This defendable space should be managed as an Inner Protection Area. For some vegetation types (e.g. Pilliga Outwash Dry Sclerophyll Forest), the low fuel loads result in a minimum APZ distance that is less than 10 metres. In these circumstances, a minimum APZ of 10 metres will be specified to provide a defendable space that facilitates fire fighting operations and hazard reduction activities. Wet Sc le roph yll Fo res ts (Gras s y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


12 14 18 23 29


12 15 18 23 29


12 15 18 23 29


12 15 18 23 29


14 18 22 28 35




Upslope/Flat >0-5 >5-10 >10-15 >15-20


13 16 20 25 31


13 16 20 25 31


13 16 20 25 31


13 16 20 25 31



Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 10 10 13


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22


10 11 14 17 22



Dry Scleroph yll Fores ts (Shrubb y) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


12 14 18 23 29


12 15 19 24 30


12 15 19 24 30


12 15 19 24 30


12 15 19 24 30


12 15 19 24 30


12 15 19 24 30


12 15 19 24 30


13 16 20 25 32


13 16 20 25 32


10 13 16 20 26


10 11 14 18 23


10 13 16 20 26

Yetman DSF


10 11 14 18 23




Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 11 13 17


10 10 11 14 17


11 13 17 21 27


10 10 11 14 18


10 10 11 14 17


10 10 11 14 17


10 10 11 14 17

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Rainfores t (All Cla s s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 10 10 10

(Fuel loads derived from Watson 2011 with calculated 50% involvement of bark and canopy fuels) Fores ted Wetland s (All Clas s e s ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 12 15 18 23


*Forested wetlands on slopes greater than five degrees are unlikely to occur. Therefore, there should be no conflict between the APZ distances and Standards for Bush Fire Hazard Reduction Works in SEPP 14 Coastal Wetlands.




Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 12 13 15 17





Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 10 11 13





Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Alpine Complex Overall Fuel Load: 17t/ha

10 10 10 12 13

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for short heath used) *Wind speed used for Radiant Heat Modelling for Alpine Complex has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide. Fres hwater Wetlands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

*Freshwater Wetlands Overall Fuel Load: 15t/ha

10 10 10 11 12

(Fuel loads derived from Planning for Bush Fire Protection 2006 with behaviour model for Shrubland chenopod used) *Wind speed used for Radiant Heat Modelling for Freshwater Wetlands has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide.


Arid Sh rub lands (All Clas s es ) EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 10 10 10


*Wind speed used for Radiant Heat Modelling for Arid Shrublands has been adjusted to 30km/h to reflect the FDI benchmark used in this Guide.



Upslope/Flat >0-5 >5-10 >10-15 >15-20


10 10 10 10 11


Pine Plan ta tions EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20


12 14 18 23 29


Gras s lands EFFECTIVE SLOPE (DEGREES)

Upslope/Flat >0-5 >5-10 >10-15 >15-20

Grasslands Overall Fuel Load: 6t/ha

10 10 10 10 10


bush fire protection for existing development · to the nature of fire behaviour and weather...

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