Know Your Code with Adrian McCabe
For Mid North grain producer Adrian McCabe, the Grain Harvesting Code of Practice and corresponding Grassland Fire Danger Index is a simple guide for growers, transporters and receival sites for when to cease operations when conditions become too severe.
Based at Hamley Bridge, Adrian says he follows the code “religiously” and combines it with his own business policies and procedures to keep family, staff and assets safe.
“The code and the GFDI is an excellent system which the whole industry is now looking to in order to determine whether it is safe to harvest, drive in paddocks or handle grain on-farm or at receival sites,” Adrian said.
Adrian keeps a close eye on weather conditions by using a hand-held weather meter in the paddock as well as a network of local weather stations, some of which are owned by other growers.
He says sharing that data is a positive step towards community safety.
“We use the information from the hand-held meter and weather stations to determine the GFDI and whether it is safe to continue harvesting.
“We will always finish when the GFDI exceeds 35 but it also depends on that day as to how early we will finish. It is a common occurrence in our area that if it is day where we think the code will be well exceeded then we and many other growers in our area will pull up early.
A CFS Perspective
By Commander Brett Loughlin, Acting Director Preparedness Operations, CFS
The South Australian Grain Harvesting Code of Practice is a great example of industry and government working together to find practical solutions to an issue.
One of the required practices of the code is to suspend grain harvesting operations when the local actual Grassland Fire Danger Index (GFDI) reaches 35.
Fixed weather stations in the appropriate areas will generally give the most accurate readings of the GFDI. For those who do not have access to nearby weather station data, hand-held weather meters are also a reliable source of local weather conditions.There may be a slight difference in temperature and wind speed between a hand-held weather meter and fixed weather station, however the results will be similar.
If using a hand-held weather meter, wind speed readings should be made in an open area at least 10 metres away from trees and other objects, facing into the wind with the meter held two metres high.
Temperature and humidity readings taken with a hand-held weather meter should be taken in the shade. These observations should then be averaged over a 10-minute period.
Using those observations, the GFDI should be measured using the following table which calculates the average wind speed for different temperature and relative humidity combinations that equate to a GFDI of 35.
For example, if the temperature is 35 degrees Celsius and the relative humidity is 14% (rounded down to 10%), then at this combination of temperature and relative humidity harvest operations should cease when the average wind speed is greater than 26 kilometres per hour.
One or two readings over an hour are unlikely to provide adequate data to enable a confident decision to be made.
The GFDI provides a numerical assessment of likely fire behaviour which is then grouped into categories. These are:
- Low/moderate – GFDI of 0-11
- Small fires, easily controlled, likely cool weather with high relative humidity.
- High – GFDI of 12-24
- Fires may present some threat to property but first attack fire-fighting is likely to succeed.
- Very high – GFDI of 25-49
- First attack fire-fighting will likely fail, fires may move quickly and threaten property, indirect strategies may succeed. The Kangaroo Island bushfires in December 2007 occurred on a day of very high fire danger.
- Severe – GFDI of 50-99
- Fires are wind-driven, will spread rapidly and may be uncontrollable with spot fires likely to occur. Total Fire Bans are declared for categories severe and above.
- Extreme – GFDI of 100-149
- Aggressive fire behaviour usually driven by strong winds. Fire-fighting is ineffective. The extreme category presents a significant threat to life and property.
- Catastrophic – GFDI of 150 and over
- Fires on catastrophic days are uncontrollable until conditions ease. The Pinery fire in November 2015 and the Wangary fire in January 2005 occurred on days of catastrophic fire danger.
While it is not currently specified in the code as to when harvesting can resume, the CFS suggests waiting until conditions have obviously moderated and making the decision in conjunction with neighbours.
Details: For more information contact CFS Headquarters on 08 8463 4200.