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Fire Danger Rating
A fire danger rating system should supply an objective answer to the question: 'What is the probability of a fire starting, spreading and doing damage today?' It enables fire managers to properly assess the levels of preparedness and the suppression resources needed to keep fire losses to a minimum. A fire danger rating system measures the variable elements which cause day to day changes in fire risk, and interprets the information gained. The information is used to:

	Define the fire season
	Determine appropriate fire prevention measures
	Assess the likelihood of fire occurring
	Determine fire suppression response and resources
	Inform the public
	Make decisions to close areas at high risk
	Issue or cancel burn permits
	Plan and conduct controlled burns

Fire Weather Index
The Fire Weather Index (FWI) System is the first part of the Canadian Forest Fire Danger Rating System (CFFDRS) introduced into New Zealand in 1980. It has proved to be a suitable fire danger rating system for this country. The FWI was evaluated for several seasons before it was introduced for the 1980-81 fire season.

The FWI is based on weather readings taken at noon standard time and rates fire danger at the mid afternoon peak from 2:00 – 4:00 pm. Weather readings required are:

	Air temperature (in the shade)
	Relative Humidity (in the shade)
	Wind speed (at 10 metres above ground level for an average over 10 minutes)
	Rainfall (For the previous 24 hours)

The Fire Weather Index has six components:

	Three Fuel Moisture Codes
	Fine Fuel Moisture Code
	Duff Moisture Code
	Drought Code

Three Fire Behaviour Indices:

	Initial Spread index		The Fire Weather Index Calulation Structure
	Build Up Index
	Fire Weather Index