Bushfire Attack Level (BAL) Assessments — Brutal Art Design Build

To understand the whole BAL Assessment process better, I’ll outline how we were instructed to assess a property.

Step One: Determine your Fire Danger Index (FDI)

The Fire Danger Index (FDI) is a measure of the probability of a bushfire starting. This factors, amongst other things, the rate of spread, intensity and difficulty of suppression according to various combinations of temperature, relative humidity, estimate of fuel state and so on.

The Australian Standard AS 3959-2009 identifies the FDI for all regions across Australia.

Step Two: Determine your site’s vegetation types

The Australian Standard AS 3959-2009 provides tables that set out visually and descriptively, seven types of vegetation classification.

Step Three: Determine the distance from the site to vegetation

After determining your site’s vegetation type, the next step is to determine the distance from your site to the vegetation itself. This is because the proximity of the vegetation to the building site will have an influence on the level of bushfire risk.

Step Four: Determine the slope of the land under the vegetation

The slope of the land towards the vegetation has a direct influence on the severity of abushfire. Bushfires have a tendency to move uphill more rapidly than downhill.

Step Five: Determine the BAL

To determine the BAL one enters the Fire Danger Index (FDI), vegetation types, distances and slopes into a given table in the Australian Standard AS 3959-2009.

Step Six: Apply the construction requirements as set out in the Australian Standard

Now you can apply the construction requirements as set out in the Australian Standard AS 3959-2009 that correspond to the BAL that you have determined.

Bushfire Attack Level (BAL) Assessments — Brutal Art Design Build