Amended Bushfire Risk Assessment and Risk Management Plan

                          Ecological Natural Area Management


7 Assessment of the Bushfire Attack Level
7.1    Assessment of the Bushfire Attack Level: Methodology
The National Construction Code of Australia references Australian Standard AS3959 Construction of
buildings in bushfire-prone areas for Deemed to Satisfy building requirements for bushfire risk
management construction of buildings. This section assesses the construction Bushfire Attack Level
(BAL) for potential houses using Method 2 of Australian Standard AS3959 to determine a level of
construction required to achieve the objective of the Standard which is to “prescribe particular
construction details for buildings to reduce the risk of ignition from a bushfire while the fire front
passes” (Standards Australia, 2018). This report uses software developed by Newcastle Bushfire
Consulting which models the Bushfire Attack Level using Method 2 of Australian Standard AS3959.
7.2    Modelled bushfire attacks
The west bushfire attack was modelled using Method 2 of Australian Standard AS 3959.




Figure 12: Map showing the modelled bushfire attack



7.3    Assessment of fuel loads
Australian Standard AS3959 allows for the use of two fuel loads for assessing Bushfire Attack
Levels for bushfire attacks from open forest and woodland vegetation communities. The two fuel
loads allow for worst-case scenarios for woodland and open forest vegetation associations.
Table 6: Surface and total fuel loads for use in AS3959 Method 2 assessments of BALs
AS3959 vegetation descriptor                         Surface fuel load                             Total fuel load
                 Forest                                     25 t/ha                                      35 t/ha
               Woodland                                     15 t/ha                                      25 t/ha

Notwithstanding the names of the two fuel loads are “woodland” and “forest”, the names are
AS3959 descriptors for fuel loads and do not relate to the Specht vegetation formation names of
open forest and woodland.

Bushfire Risk Assessment and Management Plan for a small rural subdivision at 15 Jirrama Cr, Cooroibah               March 2022

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