Appendix E - Bushfire Hazard Assessment.pdf

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    Inputs                                        Outputs
    Heat of                      18,600           Minimum distance to < 19             23 m
    combustion                   kJ/kg            kW/m²
    Flame temperature            1,090 K          Minimum distance to <                32.4 m
                                                  12.5 kW/m²
                                                  Minimum distance to < 10             38.4 m
                                                  kW/m²
     Rate of Spread - Mcarthur, 1973 & Noble et al., 1980
     Flame length - NSW Rural Fire Service, 2001 & Noble et al., 1980
     Elevation of receiver - Douglas & Tan, 2005
     Flame angle - Douglas & Tan, 2005
     Radiant heat flux - Drysdale, 1999, Sullivan et al., 2003, Douglas & Tan, 2005


The setback distance required to achieve a radiant heat flux of less than 29kW/m2 is 15.7m from the
potentially hazardous vegetation to the north. Figure 4 below designates the setback edge of
hazardous vegetation where the distance to the proposed building is 21.9m from the north-eastern
most corner, and 24.4m from the north-western most corner. This will achieve a Radiant Heat Flux
within 19-29kW/m2 which is within the sates acceptable level of risk. Compliance with AS3959-2018
for a Class 3 Structure will be required.




Figure 4: Proposed development location opposite potentially hazardous vegetation. A setback
distance from the nominal ‘Hazardous Vegetation Effective Edge Line’ of 15.7m will achieve a Radiant

Bushfire Hazard Assessment | Noosa Springs RFA17-040                                            22 April 2021
                                                  Rob Friend & Associates Pty Ltd