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Do you have a blind spot when it comes to reversing? If you want to minimise the chances of damage, injury or prosecution you really need to address the risks of going backwards
Considering how little distance trucks travel in reverse, the number of accidents that occur while doing so is huge.
The Health and Safety Executive (HSE) reports that nearly one in four deaths involving vehicles at work – in transport yards, DCs, warehouses and during deliveries – occurs while vehicles are reversing.
What the law requires
Even basic reversing alarms are not mandatory. Explaining why, the HSE says: “Reversing alarms are of limited value as they may be drowned out by ambient noise, or they may be so common on a busy site that pedestrians do not take any notice. There is also the issue that deaf people cannot hear them.
“However, there may often be situations where the frequency and difficulty of reversing movements, especially for LGVs, creates a significant workplace risk to pedestrians, where measures additional to those in the Road Vehicles (Construction and Use) Regulations, such as CCTV, are needed and are reasonably practicable.” The key phrase is “reasonably practicable” . A risk assessment might well show that it is prudent to go beyond the standard mirrors.
The HSE adds: “Employers also have a duty under health and safety legislation to conduct their business in such a way that people are not put at risk.
“Depending on the nature of their business and activities, they have to decide whether this might be aided by fitting reversing alarms or other reversing aids to their vehicles.” There is, though, a flip side to this. “Drivers can over-rely on reversing aids,” says the HSE. “This can lead to complacent behaviour.” All of which means that operators need to take a wellconsidered approach to avoiding reversing accidents.
STRATEGY
Risk assessment is the first step, starting with a review of company accident records. Do particular locations, circumstances, vehicles or drivers figure more prominently than others, pointing to heightened risks? Are artics involved in more reversing incidents than rigids because of the limitations of mirrors on articulated vehicles? Or do rigid vehicles cause more problems simply because they make more deliveries and are more likely to reverse?
It is a case of applying the usual risk strategy – remove, reduce or manage. That could involve rearranging the yard layout to give more manoeuvring space, creating designated walkways across the yard to keep pedestrians outside high-risk areas, or painting guide lines and installing wheel stops to help drivers reverse more tidily into parking spaces and loading bays. You might conclude that there is no substitute for reversing aids, particularly when it comes to situations away from the yard.
ULTRASONIC SYSTEMS
Ultrasonic reversing alarms are better known as parking sensors in cars, where they are configured to detect objects within a range of 1.5m or so from the rear of the vehicle.
Systems for trucks need a longer range – 2m or 3m – to give the driver reaction time.
They typically have four sensors across the rear of the vehicle, at an appropriate height and angle. The range of the outermost sensors should be tailored so that objects to the side do not provoke false alarms. The cab unit normally has a distance display – colourcoded and/or a digital readout – with an audible alarm that changes as the distance between vehicle and object diminishes.
Four-sensor ultrasonic systems for trucks cost from £130 to £300. Although no match for a camera, ultrasonic systems alert the driver to objects within range. “They are good for operators who experience a lot of reversing damage,” says Brigade’s marketing communications manager Emily Randall.
REVERSING ALARMS
Alarms are the most popular reversing aid, but that’s probably because they are the cheapest and not necessarily the most appropriate. An alarm warns that a vehicle is reversing but does not shift responsibility from the driver.
Nor are alarms foolproof: they don’t help deaf people and where there are a number of trucks it might be difficult to identify which one is reversing. Tonal (‘beep-beep’) alarms are also irritating.
These drawbacks have persuaded Brigade Electronics, a company instrumental in introducing reversing alarms into the UK more than 35 years ago, to change tack. “We are phasing out tonal alarms on the grounds of corporate social responsibility,” says Brigade’s marketing communications manager Emily Randall. “We feel there is a safer alternative that doesn’t cause a noise nuisance.” That alternative is a ‘broadband’ alarm, which Brigade markets under the name ‘bbs-tek White Sound’. As their name suggests, broadband alarms operate over a wider frequency range than tonal alarms. Even at low volumes they can be heard more easily above background noise, but only in the danger area – as the distance from the vehicle increases, the sound of a broadband alarm fades more quickly than a tonal alarm.
Broadband alarms also have better directional qualities than tonal alarms because their noise is more clearly focused. People at 90 degrees to the alarm’s axis hear less than those in line with it. This reduces annoyance and helps identify the vehicle in question. In a nutshell, broadband alarms are effective where they need to be but less annoying to people not at risk. Tonal alarms generally cost around £20-£30, while White Sound alarms range from about £35 to over £100. The top end of that range buys a heavy-duty model with a self-adjusting volume function that tailors output to suit ambient noise level (see Quiet Nights box overleaf). Amber Valley Developments’ Ecolarm makes a “shush-shush” sound, also claimed to be more environmentally friendly than ‘beep-beep’.
Opinions are divided about talking or speaker alarms that play a recorded message. A message such as, “Warning: this red XYZ Transport truck is reversing”, helps those in the vicinity to pinpoint the danger, but also identifies XYZ Transport as the source of the disturbance for those who are not at risk. Talking alarms usually cost £50-£70.
In the case of artics, operators need to decide if alarms should be on the tractor units or trailers. Fitting the trailer helps people locate the risk, but fitting the tractor is simpler and allows solo units to sound a warning when reversing to couple or park up.
Other reversing aids increase the driver’s awareness of something or somebody behind his vehicle, so alarms should be regarded as complementary rather than alternative.
CAMERAS
IS SEEING BELIEVING?
“When an ultrasonic system sounds a warning, are you going to get out of the cab to check what’s there?” asks Vision Techniques sales manager Andrew Kendall, summing up the attraction of reversing cameras. “Seeing is believing.” A truck reversing camera kit can cost as little as £250 or as much as £700. Apart from differences in quality, the additional cost is justified by extra features.
Good images depend on a clean lens, so consider cameras with built-in shutters that open only when reverse gear is selected. Alternatively, some cameras have integrated wash-wipe. If good camera performance in the dark is critical, check the number of infrared LEDs they have and the claimed night range: 5m to 15m is common. Most monitors have 5-inch, 5.6-inch or 7-inch screens, measured diagonally. Bigger is better, but makes it more difficult to find a suitable space in the cab. Some 7-inch monitors offer multi-image format, splitting the screen into two, three or four to allow the driver to see the output from several cameras simultaneously instead of switching from one to another. A monitor with multiple camera inputs has capacity to add more cameras in future, perhaps covering blind spots down the side of the truck. Budget £100-£150 for each additional camera. Spare inputs also allow the monitor to serve as a display for an on-board weigher or inclinometer.
Another useful feature is on-screen graphics, showing distance and parallel line markings that help drivers reverse neatly.
Van operators might like the novel rear-view mirror that includes a 4.2-inch monitor buried within it, visible only when reverse gear is selected. This disguises the monitor, making it less vulnerable to theft. Although small, it is in the most intuitive location.
▲ This ‘mirror monitor’ from Vision Techniques integrates a 4.2-inch reversing camera monitor into a van’s interior mirror
RADAR
Like ultrasonic sensors, radar reversing systems provide visual and audible warnings in the cab if they detect an object within range. That range is longer than an ultrasonic alarm – up to 10m is typical – giving ample time for drivers to react. Radar is common on RCVs that might carry out 80 or so reversing manoeuvres each day.
“The beauty of radar is that it is programmable,” says Kendall. “The size and the shape of the detection field and the sensitivity within it can be programmed, so you cut the number of false alarms.
“The range can be varied automatically to suit the speed of the vehicle, and if the distance between your vehicle and the object is increasing, the alarm will not sound.” Allan Robinson, sales director at vehicle radar specialist Sentinel Systems, says: “Radar sensors are unaffected by dirt, so they don’t need daily cleaning. That’s one of the advantages of radar over ultrasonics. We can even mount them behind a van’s plastic bumpers.” DHL has moved from ultrasonics to radar on its parcel vans.
Sentinel’s radar system for vans starts at £160; other systems for trucks are typically £600-£1,000, but can be much more. Some apply the brakes automatically if they detect anything within a pre-defined range.
▲ Refuse collection vehicles are in the vanguard of reversing aids: this one working for the City of Westminster uses a radar system supplied by Sentinel Systems
QUIET NIGHTS
Noisy reversing alarms can lead to night-time delivery bans and restrictions on an operating centre’s working hours.
It is common to mute the alarm at night, either by letting the driver silence it or via a wiring circuit that automatically turns it off when the vehicle’s lights are on. But disabling the alarm undermines the reasons for having one, and there is the additional hazard of darkness. Disabling the alarm when the lights are on is nonsensical if the lights are on because visibility is poor. And if the driver switches off the alarm, he might forget to switch it back on.
There are ways to mitigate these issues. For example, some alarms switch to a lower volume – but don’t cut out – if the lights are on. You can fit a timed cut-out switch that automatically resets itself to the on position. Alternatively, there are alarms that will only turn off (or switch to a lower volume setting) if the driver selects reverse twice in quick succession. Another solution is a self-adjusting alarm with an in-built microphone that detects ambient noise level and adjusts output to 5dB-10dB above that. The Noise Abatement Society, which administers the Dutch-inspired Piek low-noise standard for night-time deliveries in the UK, endorses Brigade’s White Sound alarms. Another option is flashing rear LED lights, wired to coincide with reversing lights. Amber Valley Developments’ new Alarmalight combines LED lights and alarm into one; if the alarm is muted or at a low volume, the LED lights flash more brightly.
CHOOSING THE MOST APPROPRIATE OPTION
Risk assessment should point to the right solution, but there are bound to be economic considerations too. Operators should consider return on investment rather than just purchase price. There might be significant variations in prices, even between kit that looks similar. Brigade’s engineering director Stuart Matthews says much depends on the quality of what’s inside: “Electronic components are tested for reliability. The best have a higher tolerance and have a better life expectancy.” Cameras and sensors are most vulnerable, so look for evidence of an ability to withstand high shock and vibration loadings. High IP (Ingress Protection) ratings are also important. For example, IP67 denotes an ability to withstand immersion in water for 30 minutes at a depth of up to one metre. IP68 is better (continuous immersion beyond a metre) and IP69K signifies resistance to pressure-washing. Good-quality systems should have longer warranties. Look, too, for modular systems with common connectors, allowing component replacement without rewiring.
The belt and braces approach is an alarm to issue a warning, a camera to see what’s behind and ultrasonics or radar to draw attention to a hazard. Over the top? Let your risk assessment decide.
INSTALLATION & MAINTENANCE
MAKE THEM PART OF A DRIVER’S WALK-AROUND CHECK Fitting typically costs around £100 (plus travel charges) for a onecamera system, usually more for an ultrasonic system with four sensors to install and wire.
It costs more to install cameras on trailers because they need additional wiring and suzie connectors. Using radio transmission instead of cable to send images from camera to monitor overcomes this, cutting installation time on an artic by around two hours. “We spent a long time finding the right radio frequency chip that minimises the delay between encoding and decoding the digital signal,” says Brigade engineering director Stuart Matthews.
A truck reversing at 3mph travels 670mm in half a second, which is why Brigade sought a fast-acting chip for its new wireless system: it works in less than 200 milliseconds.
A reversing camera is best mounted high up and angled downwards to capture a view of the rear of the vehicle as well as the area behind it. Drivers are expected to use both mirrors and reversing aids, so monitors should be mounted where they are compatible with use of the mirrors – easier said than done.
Avoid mounting a large monitor on top of the dashboard: if Vosa considers it impairs the driver’s view of the road, the truck will fail its annual test. Some monitors fit a ‘double DIN’ slot in the dashboard.
The HSE reminds employers they have a duty to ensure their employees are adequately trained, so that includes instructing drivers to use reversing aids.
Fitting reversing aids involves a commitment to keep them working. They should be part of a driver’s walk-around check and a vehicle’s regular safety inspection, just like mirrors. Camera lenses must be cleaned, so you need a safe means to reach them if they are mounted high. Ultrasonic sensors must also be kept clean. Finally, for anything more complicated than an alarm, check availability of spare parts and service support.