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 Technical

A unique set of factors make driving a 4x4 more hazardous than a normal saloon vehicle. The inherent physical characteristics of the 4x4, use in off-road terrain and a false sense of safety often give or combine to produce a situation where a roll over is more likely to occur.

US Traffic Safety statistics report that over 33% of all fatal SUV accidents are the result of roll overs. Moreover a large proportion of those incidents involved only one vehicle, most of which occur from “trip-up” scenarios resulting from driver error. SUV’s are 2.5 times more likely to roll over than conventional passenger cars.

So what are the problems with 4x4’s?

  •    A high centre of gravity: A vehicle which is designed to traverse rough terrain normally has good ground clearance. This in turn will increase the height of the centre of gravity. Whilst a few vehicles will also have a wider wheel base to help compensate, this will never be enough to match the stability of a conventional saloon. So, by their very nature, the 4x4 will be more liable to tip and therefore roll over in an accident.
  •    Use over rough terrain: Uneven ground will cause any vehicle to tip and roll and since 4x4’s are more likely to be used in these conditions roll overs are more likely to occur. Off road and semi graded roads are more likely to suffer damage/wear and changing conditions, so the unexpected can often be the cause of a serious incident.
  •    Vehicle weight: The weight of a 4x4 is normally greater than a saloon but the cab will often only have modest additional reinforcement, so when a roll over incident occurs the forces exerted will be far greater and are more likely to cause the cab to collapse. Add to that a larger payload and the effects are further exaggerated.
  •    Vehicle shape: Many 4x4's are “box-like” in shape. In a roll over incident it will be the corners that take the principal forces and so the more box-like the greater the impact and therefore likelihood of collapse.
  •    Remote environments: If your staff are expected to make long journeys in remote locations, an accident, particularly a roll-over, could turn out to be very serious. If they become injured, unconscious or incapacitated because the vehicle did not give them adequate protection then a serious injury could turn into a fatality.
  •    A false sense of security: All-terrain vehicles by reason of their size and height give the driver a sense of security and safety. Whilst in some senses this is real, the dangers of driving a 4x4 (outlined above) are much less obvious. That over-confidence the vehicle can inspire combined with lack of training and experience, can create unforeseen dangers for the driver and occupants.

Whilst highlighting the problems, 4x4's are generally safe to drive if handled carefully. Regular maintenance, careful control of vehicle use and where possible driver training will all help to reduce the risks of serious injury and death. But even the most careful implementation cannot completely eradicate the clear risks. Carefully understanding those risks, selecting the right vehicles, giving clear direction to staff all help but the backstop may be to consider roll over protection.

 

What is a ROPS?

A Roll Over Protection System is a steel structure affixed to the vehicle, designed to create a “safe zone” in the vehicle.  The structure may be inside the cab area but for modern 4x4’s is more likely to be external and part internal. The internal parts of the ROPS will help carry the load from the top of the vehicle to the floor and also to help brace the ROPS. Except in the case of a single cab pick-up, if you have no internal parts to your ROPS it will have little strength beyond that of the cab itself and the ROPS will be close to pointless.

 

How strong does it need to be?

The strength required depends upon the specific level of risk to your vehicles and whether your industry has any guidelines.

For most situations our standard ROPS will be more than adequate. This will provide 3 x Gross Vehicle Weight (GVW) vertically, 3 x GWV fore-and-aft, and 1x GVW laterally.  Most Safety Devices ROPS are independently certified to meet these standards by the Motor Industry Research Association (MIRA).

For higher risk vehicles or where accidents are likely to be more severe, Safety Devices have a range of heavy duty ROPS designed to take loads of 7.5 x GVW,5.5 x GVW and 1.5 x GVW respectively. These are Safety Devices' strongest 4x4 ROPS.

 

What other precautions should I take?

The ROPS will not be effective if other simple precautions are not also taken. Firstly, it is imperative that all occupants wear seat belts or harnesses. In a roll over event occupants can be thrown around the vehicle and unless strapped in they may be injured within the vehicle or thrown out. Secondly, any heavy cargo should be carefully stored and secured. Thirdly, we recommend that Safety Devices fire retardant paddingis used around all internal parts of your ROPS – this ensures that in the unlikely event that any part of the occupant comes in contact with the ROPS, the impact is lessened.

But you should not protect your driver and passengers at the expense of pedestrians and others. That is why we recommend as a standard that any external parts of the ROPS should not extend beyond 150mm from the vehicle and should leave gaps of no more than 50mm between the ROPS and the vehicle bodywork profile. Ideally no part of the ROPS should extend beyond the sides of the vehicle at all.

Finally installing the ROPS correctly is an imperative – ensuring it is affixed to the correct places in the vehicle, that it is braced properly, that bolts are tightened to the correct torque settings and all the padding is fixed securely. Any competent garage following our instructions will be able install a cage, but we can also provide training if required.

Paul Holmes, head of risk management, AA Business Services: "It is unlikely that many small firms will have a dedicated fleet manager responsible for reviewing health and safety policies, but there are some important steps to take. "Duty-of-care and the corporate manslaughter legislation mean that effective fleet management is essential for all businesses – regardless of their size. Companies with good safety policies have nothing to fear."

  •    Check employees’ driving licences – Fleet managers need to be confident that their employees are legal to drive and the company is aware of any speeding points they may have incurred.
  •    Ensure your fleet of vehicles is roadworthy – Employers must have policies that clearly communicate the driver’s responsibility regarding the maintenance of their vehicle. Fleet managers need to be aware that they are responsible for ensuring that cars are roadworthy, and so they need to keep a tight rein on the condition of their fleets. Companies must also make sure that drivers are shown how to make these checks correctly to ensure oil levels and tyres are monitored regularly.
  •    Make sure you have copies of your employees’ car insurance certification to ensure they are covered for business use – It is vital that private car drivers in particular are covered for driving their car for business and have the correct insurance in place.
  •    Ensure all risk policies are up-to-date and reviewed – Review operational fleet policies to ensure that statements made and standards set are achievable and do not exceed legal obligations, unless there are good reasons.
  •    Publish a drivers’ handbook – All companies should supply a driver handbook for staff members on the road, so they are aware of the company’s driving policy. Responsible driving does not stop at the end of the working day. Forward thinking employers should communicate best practice to their staff to ensure they continue to drive safely out of working hours.