Driving Lessons: Why Crashes Happen On The Mine Site

Specialist crash investigator and mine site driving trainer, George Foessel examines the reasons why light vehicle accidents occur on the mine site.

Driving a light vehicle in the resources sector presents a broad range of challenges to both the organisation and the driver. There are a number of factors to contend with, such as the wide range of environmental conditions experienced on a mine site, greatly varying degrees of driver experience and competency, and vehicles with a broad range of passive safety features. Ultimately these factors will at some stage culminate in a light vehicle incident, be it minor or major. Add to the equation the interaction with large machinery, and it all leads to a recipe for disaster. Counting back from the scene of a serious or fatal crash allows an experienced investigator to establish how the incident occurred.

Why crashes happen

Any crash is made up of a series of failures – rarely is it just one. Seldom is the driver of the motor vehicle not responsible in some form. Light vehicle safety can be broken down into three main areas:

Vehicle safety: 

Is the vehicle currently rated ANCAP 5? (Australasian New Car Assessment Program). There are additional bolt-on site specific items such as internal roll cages; external roll cages; changes to suspension, wheels and tyres; and other items that can affect the handling of the light vehicle.

Educating the staff: 

The training of drivers to understand the safety systems, and how changes to the environment will affect one’s ability to operate a vehicle safely. Additionally, strict driver assessment is essential.

Environmental factors:

In the mining sector, the environmental factors can be ever changing and significant. The environment includes road conditions, dust, mud, adverse lighting etc. The list is almost endless, however it is how these factors can result in a loss of control that is important.

The main objective of operating a light vehicle is to allow drivers to travel to various parts of their business to undertake the duties of their employment in complete safety. Therefore, drivers need to have the safest vehicle that is also fit for purpose. For example, a small two-wheel drive utility may not be ideal for towing a heavy trailer on unsealed roads due to limited traction issues. Likewise an all wheel drive vehicle may not allow drivers the same flexibility as a part-time four-wheel drive vehicle.

The safety profile of modern vehicles has advanced leaps and bounds over earlier versions of the motorcar. Although the government often lays claim to reducing the road toll, the fact is that the greatest factor is improved vehicle safety which both decreases the chances of being involved in an incident, as well as increasing the odds of surviving one.

“Going back to 1970 or even 1980, a standard light vehicle did not have airbags or even ABS brakes”.

Stringent motor vehicle design standards combined with vehicle manufacturers’ desire to build vehicles that are not just economical and reliable but also provide exceptional levels of occupant safety are beyond anything we have ever seen.

Going back to 1970 or even 1980, a standard light vehicle did not have airbags or even ABS brakes. The main safety feature on a 4WD vehicle at that time was predominantly a seat belt. Therefore, the chances of a driver surviving a crash were far less than a driver in a vehicle of today’s standards. Today we have ABS brakes (4channel), up to eight airbags, stability control systems, traction control, roll stability control, electronic brake distribution, hill launch assist, trailer anti-sway and the list goes on.

Part of my business is involved in vehicle testing to an international standard (also known as vehicle stability testing) as well as crash investigation work. This allows us to establish the effects of various levels of technology in varying conditions.

Some time ago I was involved in a court case as an expert witness regarding a light vehicle incident. As part of the court case a conversation led to the term ‘drive to the conditions’. This term is commonly used in the industry as a means of making a driver aware that they do have to ‘drive to the conditions’.

But herein lies the problem: it is a statement that holds a lot of weight. For example, a driver driving on a slippery haul road, loses control and crashes the car – did they crash the car because they didn’t drive to the conditions? It is a statement that only holds meaning to those with an understanding of what those conditions might be. For example, many Australians living in rural communities have a sound understanding of how to traverse a corrugated road. But what about a person from overseas with absolutely no knowledge of what a corrugation is? How could such a person then be reasonably expected to know how to ‘drive to the conditions’ of a corrugated road? In this instance, they haven’t ‘driven to the condition’, but they didn’t know what the condition was so therefore they cannot be expected to drive accordingly. This topic rests solely with the organisation and the driver training provider.

Pitfalls of the modern motor vehicle

One of the early pitfalls my team discovered with modern cars is that the ABS (Anti-Lock Braking System), although fantastic in most circumstances, brings its own set of problems when used in a field environment.

We began proper testing with ABS approximately three years ago, with testing centered around the ABS and its effects on various surfaces.

To establish a proper test procedure we used two forms of the latest electronics. One is a Vericom vehicle testing / crash investigation unit, the other a high level data logging system with in-built video.

Our tests were conducted using a variety of field vehicles. These tests cannot be used by an organisation to criticise ABS, as there are many variables in the testing process. The process more-so establishes that an ABS equipped vehicle can take longer to stop on a low friction surface than a non-ABS vehicle.

This comes back to driver awareness and behavior modification.

Here is a sample of our results to help those in the resources sector attain a greater understanding of the test results.

Test 1:

The testing was conducted on a low friction haul road which was wet down for consistency.

NON-ABS 50 km/h

Non-ABS tests were a best case scenario, as the driver of the vehicle was an accomplished driver and race car driver with extensive experience in this area.

There are a number of braking techniques available for non-ABS cars, including cadence braking. However, in this instance we only used the threshold braking technique which is the most common braking technique used in Australia. Threshold braking is squeezing the brake to the point before the wheel skid.

Test 2:

ABS 50 km/h

The significant factor in the second set of tests is the dramatic impact the engagement of 4WD has on the stopping distance. Engaging 4WD on a sealed surface to endeavour to shorten the stopping distance will result in drive train damage, and is not recommended.

You will note that the stopping distance more than doubles on the wet unsealed surface when the vehicle is in two-wheel drive.

We have been speaking with ABS braking manufacturers in Germany to address the issue of firmware that that would allow the ABS units to be recalibrated for mine site use. This will ultimately reduce the stopping distances for given conditions.

In addition, tyre selection is important. We tested our ABS braking system after fitting our remote area vehicle with Achillies Branded Mud Tyres, and found that the additional traction offered by this tyre offered a shorter stopping distance

“I have undertaken friction tests on wet haul roads, and the friction rate has been as low as driving on ice.”

Site-based incidents

Having personally investigated numerous site-based motor vehicle incidents, I have seen some common threads develop:

Inexperience: Some drivers graduate from university or arrive in Australia from overseas and are then expected to drive a light vehicle onsite or in a remote area with no formal training relevant to their level of experience.  In addition, in Australia we also deal with another problem – that is very low levels of competency to attain a licence, and the fact that in many states a driver is issued with a manual licence even though they have only ever driven and been tested with an automatic transmission.

Inattention: This is an interesting point, as often this is linked back to fatigue, but many of the incidents I have seen where inattention plays a part have been as a result of driver incompetence. For example; adjusting the clock on the car whilst driving, looking for a pay slip in the console, using the UHF radio to transmit, or being so focused on using the radio that the vehicle is driven off the road resulting in a roll over (more than one incident).

Vehicle condition: It is statistically highly improbable that a well-serviced and maintained vehicle that has been thoroughly inspected pre-drive could have a defect which results in a vehicle incident. This element also goes back to driver competency (have they been taught how to do a correct pre drive?) and is the culture on-site such that the pre-drive inspection is not just another tick in a box? I was involved in one such inspection after a serious incident, where the driver had ticked all the boxes as to the vehicle being OK. Ten minutes later there was an incident and the vehicle was examined by our forensic mechanic. We found that the vehicle had 27 faults that should have stopped it from being driven. Interestingly these 27 faults included extensive corrosion which was not picked up by the local garage that was tasked with authorising the vehicles for use on-site. If this process is taken seriously, site vehicles should be subjected to a six monthly safety inspection where the inspector is held accountable for the safety inspection.

Driver competency: This is an absolute minefield. Some sites work on the theory that if you have a drivers licence you can drive onsite. That is about as logical as saying that if you have a drivers licence you will never crash a motor car. It is assuming a level of competency. The truth is that the level of competency just isn’t there. Our post licence training programs run at a 10 percent failure rate. Why is that? Well it’s simply because it’s a reflection of how easy it is to get a licence. As mentioned previously, in some states you do your test in an auto and presto you get the manual licence for free. I have attended three crashes where drivers in automatic cars (so only two pedals to choose from) have hit the accelerator instead of the brake and held the throttle flat until impact. It causes you to question the process of our licensing system.

Next we have drivers from all around the globe arriving in Australia with a drivers licence from their country of origin. For a number of these we knew we had a problem when they were filling out our entry requirements and nominated two of the three pedals as brake pedals, and also had no idea as to the shift pattern on a manual transmission motor car. In my experience, although some International drivers possess a licence that bears their name, by all accounts their first time attempting to drive was on the day of their short-lived driving course. Arrive for course at 8am, back on the way home at 9am!

Unexpected changes to the conditions: The difficulty on a mine site compared to the public road is that when it rains on a normal tar sealed road it can be seen and smelt, therefore an adjustment of speed would be the logical course of action for the driver.  However on a mine site, water trucks are deployed to wet down the roads to suppress dust for both environmental and safety reasons.

The end result is the water on the road surface results in dramatically reduced friction / traction.

I have undertaken friction tests on wet haul roads, and the friction rate has been as low as driving on ice.  This is particularly prevalent on clay-based surfaces.

Here are two examples (of many) where a driver could not reasonably be expected to adjust to the conditions:

• Water cart operator soaks down a section of road, commencing the water down process half way through a sweeping bend in an 80km zone. Next car comes through with the first half of the corner being dry only to find himself in the middle of a corner with drastically reduced traction travelling at unsuitable speed resulting in a loss of control and roll over.
• A driver is travelling along a section of haul road at 80kph and crests a hill. Unbeknown to the driver a water cart has recently watered the downhill section over the crest resulting in a 200 plus metre skid and roll over.

I would strongly encourage companies to look at the procedures for water carts to determine appropriate areas and times to wet down roads, but additionally look at strip watering. My favourite watering technique for vehicle safety is strip watering whereby the water is dispersed to appear like a pedestrian crossing of wet and dry patches. After all the road surface is about friction.

I’ve heard all the excuses

When a driver has crashed a motor vehicle for no apparent reason, it can be assumed that he or she has failed to exercise proper care and control over the motor car. However talking with drivers of light vehicles involved in an incident provides some entertaining responses:

80kph roll over:
“If I was driving a Nissan instead of a Toyota it wouldn’t have rolled.”
(Roll angle of both cars is the same)

Car skidded 140 meters on a dry road surface:
“I was only doing 40kph”
(We tested the surface and at 40kph a vehicle could stop in 14 metres)

IVMS says you were travelling at 95kph in a 40 zone:
“No I was definitely doing 40”
(But the IVMS speed matched the engine rpm which matched the gear ratios of the car)

How fast were you travelling?: 

“I don’t know. The instrument lights were not working”
(When questioned they had not been working for years yet were never fixed.)

When did you notice the change in road conditions (night time)?
“I didn’t. The truck only has one headlight”
(When questioned the vehicle had one headlight for over 12 months yet no one bothered to repair it)

“We have been speaking with ABS braking manufacturers in Germany to address the issue of firmware that that would allow the ABS units to be recalibrated for mine site use.”

The list of excuses goes on and on and make for some truly entertaining moments…

Light vehicle safety in the resources sector is a real challenge for any organsiation, but an investment in the right equipment, the right training, and developing a great safety culture will definitely see a massive improvement in driver standards.