Att 2 - BAL Report

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                                                                                  www.bushfireassessmentqld.com.au
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specifications are based on heat flux exposure thresholds which have been categorized into six Bushfire
Attack Levels (BALs), listed in ascending order of threat level below:

    •   BAL- LOW

    •   BAL- 12.5

    •   BAL- 19

    •   BAL- 29

    •   BAL- 40; and

    •   BAL- Flame Zone (FZ)

These categories are expressed in kW/m², as such, the lower the category value the lower the radiant heat
exposure. The highest level of bushfire attack is BAL-FZ, which indicates direct exposure to flames.
Determining a BAL rating for a proposed development can be ascertained using either Method 1 (Clause 2.2,
AS 3959-2018) or Method 2 (Appendix B, AS 3959-2018). Method 1 is a simplified procedure, whereas
Method 2 is more detailed and is utilised when a more precise result is required.

1.4. Other Site Constraints

The scope of this report does not include an assessment of threatened species, sites of Aboriginal
significance, heritage, or other environmental constraints. It is recommended that relevant experts are
engaged to undertake these assessments as required.




     2. BUSHFIRE ATTACK LEVEL ASSESSMENT METHODOLOGY

2.1. Bushfire attack level assessment methodology

Assessment methodology for the subject site has been conducted in accordance with a Method 2 assessment
per the Australian Standard Construction of buildings in bushfire-prone areas (2018) including amendments,
and with reference to Bushfire Resilient Communities – Technical Reference Guide for the State Planning
Policy State Interest ‘Natural Hazards, Risk and Resilience – Bushfire’.

2.2. Desktop Assessment

A desktop assessment of the subject site and surrounds using high resolution imagery was conducted to
broadly assess the site characteristics and relevant information. QSpatial data was obtained to produce site-
specific Bushfire Prone Area (BPA) mapping per the SPP and Maximum Landscape Slope and Vegetation
Hazard Class mapping per Bushfire Resilient Communities (2019). This is followed by an on-site field
assessment and ground-truthing.




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