Recently our friends across the Tasman have been looking at truck fires and their causes and what can be done to prevent them. This is an issue that also affect us here in New Zealand,
In Australia the National Heavy Vehicle Regulator has even published a safety bulletin that, effectively, informs operators to use their common sense
Similar to advice that has been offered in NZ previously they suggest engine bay cleanliness is one method of ensuring that there is nothing to feed a fire. They also say that the very act of cleaning the engine bay means you will see such things as worn or damaged insulation that could fall onto the hot engine or exhaust and catch fire as well as frayed or perished wiring or fuel lines that could ignite or support a fire. Common sense really.
Brakes on both trucks and trailers are also a source of concern. Brakes develop very high temperatures that could cause a fire especially if, through lack of maintenance a brake is not adjusted correctly leading to the brake dragging, an airline fault meaning that brake disengagement at the extremity of a combination is slow or brake imbalance across the axle meaning one brake has to work much harder (and hotter) to provide the required deceleration. These increased temperatures are transferred to the tyres through the wheels and the wheel bearings again increasing the risk of fire. More common sense.
With wheel bearings there are a number of issues that could lead bearing overheating and combusting such as the brake issues described above as well as incorrect preload on the bearing, the bearing running dry due to substandard maintenance or having the grease washed out due to immersion or even aggressive high-pressure cleaning. Again, when a wheel bearing fails, its temperature increases significantly, which can result in the bearing lubricant or tyres (via heat transfer from the wheel rim) catching fire. Still more common sense.
Tyres are a further risk factor. Tyres are designed to operate within a specified heat range but there are a number of factors that might cause a tyre to overheat and possibly catch fire including issues with the brakes and wheel bearings as stated earlier as well as a tyre rubbing on vehicle components (suspension, guards, adjacent tyres, etc.) or being partially or fully deflated. All these issues should be regularly monitored to keep risk to a minimum. More common sense.
A further factor in the incidence of truck fires can be loading, or more particularly, the types of load carried. For example, with a mixed commodity load one part of the load may contain a possible ignition source such as batteries while another part of the load is a potential fire fuel source/accelerant such as cardboard. In these circumstances it is important that these loads are segregated with no chance to come into contact. Common sense again.
To reduce the risk of truck and truck and trailer fires heavy vehicle operators should:
- Use common sense.
- review the common causes of fires, identify those that may be most present in their fleet and introduce procedures to minimise their effects.
- review their maintenance systems to remove or reduce any risk factors.
- ensure those who carry out servicing or modification on higher-risk components or systems on their vehicles, such as electrical systems, have measures in place to verify that fire risks are not introduced (i.e. persons appropriately qualified, work performed to relevant standards, work procedures or checklists completed etc).
If common sense is the answer then a lack of common sense must be the problem. So why is common sense lacking? Is there too much time pressure to allow you to take basic precautions? Are your margins so tight you can’t afford to take these basic precautions or are you too complacent?