Refernce Documents - RAL25 0001

                 Fuel load, VHC, landscape slope and FFDI were represented spatially in 10m resolution input
                 rasters. The input rasters were modelled using GIS software to generate a model of potential
                 fire behaviour for the 5% AEP event. Maps 7 to 9 indicate the site-specific modelled inputs for
                 potential fuel load (Map 7), maximum landscape slope (Map 8) and fire weather severity/FFDI
                 (Map 9), respectively.

                 PFI was calculated in accordance with Leonard et al. (2014a):

                                                                 𝑃𝑃𝑃𝑃𝑃𝑃 = 0.62 𝑊𝑊 2 𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝑒𝑒 (0.069𝜃𝜃)   (Equation 1)

                           Where: 𝑃𝑃𝑃𝑃𝑃𝑃 = Potential Fireline Intensity (kW/m);

                                       𝑊𝑊 = Potential fuel load (tonnes/ha);

                                       𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹 = Fire weather severity/FFDI; and,

                                       𝜃𝜃 = Maximum slope (degrees).

                 Resulting PFI was then classified into one of three (3) potential bushfire hazard classes, as
                 outlined in Table 1.

                 TABLE 1: POTENTIAL BUSHFIRE INTENSITY CLASSES (SOURCE: LEONARD ET AL. 2014).


                    Potential Bushfire Intensity          Potential Fireline Intensity
                    Very High                             40,000+ kW/m

                    High                                  20,000 – 40,000 kW/m

                    Medium                                4,000 – 20,000 kW/m

                 5.2.3 RADIANT HEAT LUX

                 Where modelling results indicated that the proposed development was located within a
                 bushfire prone area and/or potential impact buffer, radiant heat flux and associated Bushfire
                 Attack Level (BAL) were calculated according to the View Factor Method described in AS
                 3959:2018 (Standards Australia 2018). Separation distances for achieving the various BAL
                 levels were calculated using the SPP Bushfire Asset Protection Zone Width Calculator
                 (Queensland Fire and Emergency Services 2019), including inputs based on:

                    ● Distance(s) between the closest edge of the proposed lots and the edge of areas of
                        potential fireline intensity, with radiant heat flux calculated consistent with the height of
                        the adjacent vegetation, maximum flame angle and modelled flame lengths.
                    ● Fuel loads derived from the SPP vegetation hazard class input map and site-based
                        survey.
                    ● Effective and site slopes under the classified vegetation were calculated from the SPP
                        landscape slope input map.
                    ● An FFDI of 47 based on the 5% AEP event as per Leonard et al. (2014).


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Document Set ID: 23448646
Version: 1, Version Date: 13/01/2025