Q & A
Q. Is burnover protection really necessary?
A. Australia is a world leader in bushfire frequency and severity. There have been 38 bushfirefighter fatalities in Australia since 1980 not to mention injuries and near misses. The firefighting agencies have worked tirelessly to improve the safety of their trucks. However, in spite of all the time and money spent on the problem, the reality is that a prolonged, serious burnover will destroy the vehicle leaving the crew with nowhere to go.
Q. Isn't protection fitted to trucks already?
A. Yes and they work very well up to a point, however there are some issues :-
- the water reserve only gives protection for about five minutes
- spray systems are susceptible to pump malfunction including engine smoke ingestion and oxygen starvation
- research by Brown, Nicholl, Mangan, Leonard, Abbott et al. around 20013 indicates that in a serious burnover, the truck will catch fire and put the crew at risk death or serious injury
- the burning truck then becomes its own fuel source as tyres, hoses and plastics burn to destruction.
(Dr Neil Burrows, called as an expert witness in the coronial inquest into a fatality at the Black Cat Creek fire had this to say :-
" Dr Burrows explained that there is no firetruck built to withstand those sorts of intensities." [23Mw/m]).
Q. Isn't the truck cab the safest place to be in a fire?
A. For low to moderate intensity fires, yes. The problem is that we cannot predict the severity of a burnover but we do know that a worst case scenario event will destroy the truck forcing the crew to escape into a firestorm.
Q. What is different about this system?
A. The triple wall construction with double air space insulation. It will stand 1000C on the outside for extended periods (>20 minutes) and preserve the inner wall temperature at a safe level. It uses no water or chemicals and is mechanically very simple. It also removes the crew from the cab with its potentially deadly flammable plastic interior.
Q. How long does it take to deploy the Shadrach?
A. Only a few seconds including sliding it out into position. The device can be extended without being dropped if the situation looks threatening. Crew can freely continue to operate the pump and hoses and then if a burnover is imminent, it takes only about three seconds to lower the shield.
Q. Is it expensive?
A. The final cost can only be established for manufacturing in quantity but should be well under $10,000 fitted. On the other hand, what price should be put on firefighter safety? In the context of the overall cost of a new tanker ($200k+) it is very affordable. Nil maintenance.
Q. How much more work needs to be done on the design?
A. The Shadrach has been extensively tested and is ready for manufacture. We have selected a benchmark heat flux level of 100kW/sq.m based on work done by the CSIRO over many years. Our test rig of four LPG burners equates to this level of radiation. The video clips above demonstrate the Shadrach performing safely at this level of heat flux for extended periods.
Q. Isn't it a disadvantage having to leave the cab?
A. Except for the driver, the crew is usually outside the cab on the hoses. In a bad burnover, the truck itself will catch fire and the cab occupants will be forced to escape the burning cab into a hostile environment. The Shadrach is designed to provide a safe refuge even if the truck burns to the ground.
Q. Does deploying the Shadrach disable the truck?
A. No. In the case of a near miss, it takes only a couple of minutes to retract the Shadrach and continue firefighting.
Q. Why "Shadrach"?
A. Daniel 3:50.