'Tis the season to be wary of combine harvester fire risks

Author: | Date: 29 Nov 2011

Graeme Quick

’Tis the season to be wary of combine harvester fire risks

The Grains Research and Development Corporation (GRDC) is reminding growers of the need to reduce the potential for combine harvester fires this summer.

Preventative and precautionary measures are essential in limiting the fire risk, according to the GRDC and farm machinery safety authorities who say that Australian broadacre harvest conditions are arguably the most hazardous in the world for fires.

Internationally-recognised agricultural engineer and harvester expert, Dr Graeme Quick, whose research into harvester fires is supported by the GRDC, says the key to avoiding harvester fires is diligence in clean down and inspection, and postponing paddock work during the highest fire risk periods.

“Suitable equipment and operator diligence in a fire-prone environment is critical, and this calls for systematic preparation and prevention procedures,” Dr Quick said.

“All operators should equip their machines with at least two fire extinguishers. A high capacity air compressor with air lances should be on board or at hand. Regular blowdowns are essential and in the worst conditions a blowdown may be needed as frequently as every half hour, or bin round.”

The issue of combine harvester fires was investigated last year by Dr Quick, who was engaged by the GRDC to look at the causes of a spate of blazes and to prepare a set of recommendations for reducing the impact and consequences of combine harvester fires.

Dr Quick canvassed professional advice and industry opinions in Australia and the United States about combine fires, then investigated harvester fire incidents in southern Queensland, northern New South Wales and on the Yorke Peninsula in South Australia.

The most common cause of harvester fires was in the engine bay, where material can collect on hot components such as the exhaust manifold and turbocharger.

“Crop materials collecting or clumping on hot components can ignite, then embers can drop down or are blown around the machine and into the crop to cause smouldering and spot fires,” Dr Quick said.

“Others causes are failed bearings or brake problems, electricals, fluid leaks and rock strikes. Incidentally, the evidence does not support static electricity as a prime cause of harvester fires, so that's another reason for extreme care in harvester hygiene.”

The following is a checklist developed by Dr Quick and endorsed by the GRDC, for reducing fire hazards on combine harvesters:

1. Recognise the big four factors that contribute to fires, namely relative humidity, ambient temperature, wind and crop type and conditions. Stop harvest when the danger is extreme.
2. Redouble service, maintenance and machine hygiene efforts at harvest on the days more hazardous for fire. Follow systematic preparation and prevention procedures.
3. Use every means possible to avoid the accumulation of flammable material on the manifold, turbocharger or the exhaust system. Be extra wary of tailwinds that can disrupt the radiator fan airblast that normally keeps the exhaust area clean.
4. Be on the lookout for places where chafing of fuel lines, battery cables, hot wires, tyres, drive belts etc, can occur.
5. Avoid overloading electrical circuits.
6. Periodically check bearings around the front and the machine body. Use a hand-held digital heat-measuring gun for temperature diagnostics on bearings, brakes etc.
7. Drag chains, or better still drag cables or grounding conductors, may help dissipate electrical charge but are not universally successful in all conditions. In certain conditions a drag chain could even start a fire from rock strikes. On the other hand there are some invaluable fire-suppressing options on the market.
8. Use the battery isolation switch when the harvester is parked. Use vermin deterrents in the cab and elsewhere, as vermin chew some types of electrical insulation.
9. Observe the Grassland Fire Danger Index (GFDI) protocol on high fire risk days. Don’t jump to a conclusion that static electricity is a cause of fires; the evidence doesn’t support this as a prime cause on harvesters.
10. Maintain two-way contact with base and others. And keep an eye out for hazards on machinery during the season.


Caption: Dr Graeme Quick, an internationally-recognised agricultural engineer and harvester expert, was engaged by the GRDC to look at the causes of combine harvester fires.

• For further information, contact Dr Graeme Quick on 07 5494 9920 or GRDC Program Manager, New Farm Products and Services, Paul Meibusch, on 02 61664500.

• This media release and other media products are available via www.grdc.com.au/media

Region North