9 January, 2013 9:20AM ACDT

A farmer's invention: Fighting fire with fire

The Remote Outer Border Fire Control System (ROBS) uses the outer rear wheel of the fire truck to help establish a very clean, well defined and safe edge to a back-burn.

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The back-burn can be laid dawn as fast as the truck can travel across the paddock and it's important the driver of the truck ensures he picks a good line to avoid clumps of material,

Rob England, a farmer from outside of Lucindale in the South East, developed the system intially as a means of doing accurate controlled back-burns around problem areas of fires - burning trees, stumps, native vegetation.

He went on to develop the concept to use it as a means of quick and efficient attack and control of going fires.

"I developed it in 2006, put it up as an entry to 'The New Inventors' but it was rejected 'as unlikely to be commercially developed' as I was freely giving away the 'intellectual property'.

"I sent copies of the methodology to the Cheif Officer of every State and Territory Fire Fighting Organisation - and told that they had all the fire suppressant technology required, but would develop it themselves if they thought it may be applicable, and have supplied a copy of the training package and a hose mount to all the Groups within Region 5, and every Fire Brigade within the Lacepede Group.

"Amazingly, most still persist with attacking the fire wherever it is, and however intense it may be, ignoring the benefits to crews and vehicles, and the ability to put out so much more fire, and so much quicker, with the water carried on the fire truck," he said.

Mr England says the system "allows the resources carried on one fire appliance to be extended to extinguish up to five times the fire perimeter extinguished by direct attack, in less time, and with less risk to personnel and equipment."

Follow the photos to see how it works

Click play to listen to audio with Rob England

How it works

1. A Fire Appliance is used to wheel roll, the flammable material some distance away - or REMOTE - from the fire to be contained which is to the left of the truck. As the wheel rolling progresses, two nozzles are used to wet down the flammable material adjacent to the OUTER, or rear wheel of the Appliance away from the fire.

The driver's role is crucial. He must :-

- Start from an anchor point - a road, track, or dead/extinguished fire edge where the fire can't burn behind his start point. Otherwise, start with another truck creating a Border in the opposite direction.

- Select the material to be rolled so that a continuous burnt edge can be created. (Any non burnt area will dry and carry fire later - potentially breaching the Border.)

-Avoid bushes and sticks and other vegetation which may provide potential Border breaching burn-unders.

-Select the stand-off distance of travel from the fire to be contained, so that a Border of sufficient width is established to stop the fire. The stand-off could be as little as two metres along the up wind side of a fire, 10 to 20 metres along the rear flanks of a fire, and increasing to 100 metres or much more on the head-ward flanks, and across the head of a fire. This stand-off distance will depend on the temperature and humidity, types of flammable material, wind direction, speed, and change-abiilty, and rate of fire spread.

2. One nozzle must wet the material to the ground surface using a confined jetting pattern, while the other nozzle uses a cone pattern to wet the standing material.

3. The appliance side, wheel and tyre shield the rolled material from the wetting spray, ensuring that it remains dry for subsequent lighting.

4. Lesser amounts of water and fire re-tardent may be applied in lower density vegetation, achieved by either partly closing the control tap, or running the truck at higher forward speeds. Sufficient pressure must be maintained for the jet nozzle to still wet the material to the ground surface.

5. The wheel rolling action compacts the flammable material into a layer close to the ground, excluding much of the oxygen and creating a shield from much of the wind, while the tyre marks clearly delineate the boundary between wet and dry material.

6. A fire is lit along the dry tuft of grass left between the dual wheels immediately after the passage of the appliance, and must be lit before the wetted material can dry out enough to support a fire.

7.The resulting low intensity fire burns the compacted material on the tyre rolled track, and goes out when it reaches the wetted zone, creating a dead BORDER. Low intensity fires require little water to extinguish, so resources go much further.

8.In taller, or higher fuel loads, or extreme weather, a second or third truck can also do rolling and wetting runs, with the lighting being on the last truck's wheel marks. This gives a lower intensity initial fire and the rolled wetted material incurrs less drying so is unlikely to catch fire. However the wider wheel rolled area within the Border area causes slower establishment of the Border, and a greater stand off from the fire being controlled will be required - particularly if on the windward side, or at or near the head of the fire.

9.The other side of the fire burns away from the now dead edge, progressively creating a BORDER of ever increasing width as it burns towards the fire to be contained. Note how the break fire is rapidly drawn towards the wild fire as they come together due to the updraft.

10. Increased fire intensity occurs as the two fires meet, but as long as the BORDER has been created far enough from the fire to be contained to allow a Fuel free zone of sufficient width to be created, extinguishment of the fire to be contained will be effected.

11. The REMOTE BORDER -or Fuel Free Zone - placed where the Fire Controller Chooses, rather than where the fire happened to be, allowed minimal effort fire control to be effected.

12. The crews - after initial establishment of the Remote Outer Border - can watch and patrol from vantage points away from the stress of the smoke, heat and danger, and be ready to stop any ember escapes which may occur.