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Past Issues

May 2005

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Elsewhere in this special interest report we spell out the impressive technological improvements that have been made to modern braking systems. Are these making a difference out there? What's the reality on the ground? For this, we approached Laurie Merchant, (IEng. .MSOE.MIRTE), a man who has many years experience investigating braking systems for accident claims. The news is not good. Here it is in Merchant's own words...

In 1999, I sent several photographs to FleetWatch and commented on the condition of the brake systems of several of the vehicles I had inspected over the years. Here we are - six years later - and with brake systems having reached the electronic age, one would think things would have improved. Unfortunately, I regret to inform you that the condition has deteriorated.

Let's first look at the legal requirements for braking systems contained in Act 93 of 1996, Road Traffic Regulations under the heading Specifications for Brakes. Reg 154 states:

(1) Subject to the provisions, of sub regulation (2), no person shall, after 1 January 1995, operate on a public road, a goods vehicle, the gross vehicle mass of which exceeds 3 500 kilograms, a mini-bus, bus or tractor which was registered for the first time on or after 1 January 1986, unless the brakes fitted to such vehicle comply with the Standard Specification of the South African Bureau of Standards SABS 1207 - 1985 "Motor Vehicle Safety Specification for Braking" as published by Government Notice No. R. 6 of January1986 or the Standard Specification of the South African Bureau of Standards SABS 1051 - 1980 "Motor Vehicle Safety Specifications for Braking".

The relevant part of the above Act is: Since the January 1, 1995 all vehicles over 3 500 kilograms registered on or after 1st January must comply with the requirements of SABS 1207 specification for braking. 

Most of the trucks imported into South Africa exceed our SABS 1207 and are fitted with ABS - some with EBS (electronic braking) traction control and a host of other features. Many of the trucks and trailers now have disc brakes and wear indicators for the brake pads. At the beginning of this year, all new trailers over 3 500 kilograms were required to be fitted with ABS and automatic slack adjusters. All these features are designed to make vehicles safer by reducing stopping distances and making them more stable regardless of road surface or weather conditions.

Reading the above, one must ask the question. Why then are there so many accidents involving trucks and buses? The answer is a simple one: Maintenance - or should I say a lack of maintenance 

Operators should take note that regardless of extended service periods, a programme should be implemented where the vehicle (trailers included) should be inspected for defects every 10 000 kilometres. For buses, it should be every month regardless of kilometres travelled. But most important is that the inspections must be done by competent staff.

I consult for various insurance companies, the DoT and the Road Traffic Inspectorate in KwaZulu-Natal and from my experience, I estimate that 9 out of 10 vehicles I am asked to inspect are not roadworthy. To highlight this, herewith are examples of the condition of some of the vehicles. Note that several have disc brakes and ABS so these vehicles are not old. However, regardless of the age of the vehicles, they all had one thing in common, a lack of maintenance.

FRONT AXLE - right side - no slack adjuster or yoke	FRONT AXLE - left - no slack adjuster or yoke
FRONT AXLE - right - no brake shoes in drum. Shoes missing and drum rusted	FRONT AXLE - left - no brake shoes in brake drum - drum rusted

 

 

 

 

 

Although no bus inspections have been given, I can assure you that the condition of several that I have inspected have been beyond belief. A bus was put back into service without a nut on the steering drag link ball joint. The ball joint eventually parted company with the drag link which resulted in several dead passengers.

I have inspected a vehicle with over 30 defects which had passed a roadworthy test only three months prior to my inspection. I have also had arguments with test stations that pass vehicles because the brake efficiency meets the brake roller test requirement. However, the brake linings are worn down to such a degree that the rivets contact the brake drum when the brakes are applied. And this is in spite of them having to follow SABS 047 - The testing of motor vehicles for roadworthiness which states:
Edition 4, 5.54 Braking system 
Specific items 
Reject if any of the following are found: 
a) Excessively worn linings, pads or discs; 

Where are the apprentices?
Brake systems are becoming more and more efficient and yet more and more complicated. Given that the level of technical capability available in the industry to maintain a simple dual circuit conventional air brake system is a problem, I have to ask where are the apprentices who are learning about the new systems? Who actually employs apprentices? I do not know of one company. 

I also contend that the vehicle manufacturers' technicians who have access to the computers needed to make changes to the brake system settings have certainly had training on how to do so but do not fully understand the function and various setting of the valves that they can reset.

An example of this was a vehicle with EBS coupled to a 20-year-old trailer. The driver complained that the trailer was pushing the truck tractor. The vehicle manufacturer's distributor tested the brakes on a roller test machine and pronounced the brakes to be working correctly because the reading on the roller test machine for the truck tractor and trailer exceeded the required brake efficiency.

What they failed to check, however, was the air pressure difference between the truck tractor and the trailer to achieve the brake efficiency. When the brakes were applied, the truck tractor brake chambers had 2-Bar air pressure supplied to them before any air pressure was being delivered to the trailer brakes. It should have been 0.75 bar delivered to the trailer brakes before air pressure was supplied to the brake chambers on the truck tractor. The roller test alone cannot detect this problem.

What really astonishes me is that operators will invest R1-million in a vehicle and then let it deteriorate to the point where it is unroadworthy. The vehicle then has an accident and the insurance company repudiates the claim because the policy states that the vehicle must be kept in a roadworthy condition according to the Road Traffic Act. There is no logic at work here.

Where to from here?
What is really needed is for the DoT to get tough on operators who blatantly operate unroadworthy vehicles. Operators who do so should have their operators licence cancelled. Too often the driver is charged while the owner/operator gets off scott-free.

Law enforcement must concentrate on prevention. How many times have you seen a traffic cop who is manning a speed trap let a blatantly unroadworthy vehicle pass by without stopping it purely because the vehicle is not speeding. Come on guys: Law enforcement should not appertain to only one aspect on a certain day and another on the following day.

What really concerns me is that in another six years, I will be talking once again to FleetWatch and will begin with: I regret to inform you that the condition has deteriorated. My plea - through FleetWatch - to all operators is to please ensure that this won't be the case.