Compiled Plans & Documents OPW18-0342 02

                                                                Retirement Living & Aged Care Facility
                                                                       Grasstree Court, Sunrise Beach


4           Understanding Bushfire Hazard
Bushfires have long remained a fundamental characteristic of the Australian bush landscape, and
likewise Australians have long retained a strong affinity with bush environments. There remains a
number of common factors which are associated with bushfire events and these include the
incidence of fire weather, availability of fuel along with its type, structure and continuity or
fragmentation, and development at urban / bushland interface.

4.1         Bushfire Attack
Bushfire attack refers to the various methods in which bushfire may impact upon life and property
and principally encompasses:

     •    Direct flame contact

     •    Ember and firebrand attack

     •    Radiant heat flux

     •    Fire-driven wind

     •    Smoke

During the progression of a bushfire event, these methods interact either exclusively or in concert. It
is estimated that approximately 80 to 90 per cent of buildings located within 100m of the bushland
interface are lost to bushfire, hence the relevance of statutory provisions and recommendations
implemented across Australia which respond to various types of buildings within 100m of adjacent
classifiable vegetation.




                                               Fire Front
  •Increasing wind impact                       Impact                   •Continued ember
                                                                          attack
  •Developing ember
   attack                              •Maximum wind impact              •Continued flame and
  •Ignition of spot fires              •Maximum ember attack              burning of larger/denser
                                       •Maximum radiant heat              materials
                                        attack                           •Decreasing radiant heat
                                       •Possible flame attack
                                       •Smoke
                                                                                   Post Fire
           Pre Fire Front
                                                                                    Front



             30 Minutes                5-10 minutes (approx.)                 1-4+ hours

Figure 3 - The typical phases of bushfire attack (derived from Ramsay & Rudolph, 2003)




Status: Final                                                                                 March 2019
Project No.: 18-030                                                                              Page 15