Refernce Documents - RAL25 0001

                                                Fire                                                Fireline
                                                                         Potential
                       Slope                  Weather                                              Intensity
                                                                         fuel load
                                              Severity                                               (PFI)



                 FIGURE 3: METHOD FOR CALCULATION OF POTENTIAL FIRELINE INTENSITY (PFI) (LEONARD ET
                 AL. 2014).




                 Areas of potential fireline intensity include potentially hazardous vegetation that could
                 support a significant bushfire or be subject to significant bushfire attack. It includes
                 potentially hazardous vegetation with a Medium (4,000 – 20,000 kW/m), High (20,000 –
                 40,000 kW/m) or Very High (40,000+ kW/m) Potential Bushfire Intensity. Bushfires in these
                 areas have the potential for high to extreme levels of flame attack, radiant heat and ember
                 attack. Land adjacent to bushfire prone areas is also at risk of significant bushfire attack from
                 embers, flames or radiant heat. The latter are identified as potential impact buffer areas and
                 include all land within 100m of areas mapped as Medium, High or Very High Potential Bushfire
                 Intensity. Together, the areas of potential fireline intensity and potential impact buffer form
                 bushfire prone areas.

                 Vegetated parts of the landscape which support fireline intensities of less than 4,000 kW/m
                 are categorised as grassfire prone areas or low hazard areas (e.g. rainforest or water or non-
                 vegetated urban areas).

                 The SPP methodology was developed to overcome limitations of the approach adopted by
                 the previous State Planning Policy (SPP 1/03), including the failure to consider regional
                 differences in fire weather severity, effective slope and the diversity of vegetation types and
                 fuel loads across Queensland (Leonard and Blanchi 2012). The new methodology estimates
                 the potential fireline intensity at the landscape scale. Fireline intensity is a standardised
                 measure of the rate that an advancing head fire would consume fuel energy per unit time per
                 unit length fire front (Byram 1959). As noted by Leonard et al. (2014), the benefits of utilising
                 fireline intensity as the principal measure of bushfire hazard, is that it can also be used to
                 estimate the potential flame length (e.g. Alexander and Cruz 2012) and radiant heat flux
                 based on distance from hazardous vegetation. Radiant heat flux can then be used to
                 determine:

                    ● minimum separation distance from hazardous vegetation needed to afford safety levels
                        to people and/or buildings (Zarate et al. 2008; Newnham et al. 2013), and




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