Tractor Trailer Cameras & Blind Spots: How Can Accidents Be Prevented

by Terry Bryant

Blind spots are a liability for any vehicle, but they are particularly troublesome for 18-wheelers. The sight lines around a commercial truck are blocked by long and wide trailers, often putting the driver in an uncomfortable position. Of course, commercial drivers are trained to account for these blind spots, but even if a driver moves carefully and is alert at all times, they can easily fail to see other motorists when changing lanes, turning or backing up their vehicle. Even worse, other motorists are typically unaware of just how extensive these blind spots are, and may be invisible to the truck driver without realizing it.

Road visibility is a critical element of safe driving, which is why some commercial truck operators are turning to tractor trailer cameras for additional eyes on the road.

Blind Spots:

With blind spots a truck driver faces making difficult traffic maneuvers with extremely limited information coming to them through their mirrors.

But how limiting are blind spots, really?

It depends on the size and shape of a truck, but in general, blind spots extend for a couple car lengths on either side of the truck, and for several car lengths behind the truck. Some 18-wheeler drivers have little visibility up to 50 meters directly behind their vehicle, which means on high-traffic roads and on residential streets, there is almost always a car around the truck that cannot be seen. It’s common for motorists to get frustrated at how slow large trucks move and switch lanes. The reason for that slower movement is that a truck driver assumes that others are always in their blind spots, and know that sudden traffic maneuvers can result in tragic consequences.

In 2011, the National Highway Traffic Safety Administration, or NHTSA, released a 520-page report on the problems associated with commercial truck’s blind spots, and how tractor trailer cameras can provide a workable solution. In its report, the NHTSA used data from the Large Truck Crash Causation Study, or LTCCS, to track the causes behind commercial truck crashes. According to the LTCCS data, about 7% of all accidents are the result of blind spots affecting traffic maneuvers, and this number is consistent from year to year.

This data is corroborated by a 2009 sampling from the NHTSA’s General Estimates System, or GES. The GES reviews information from police reports to determine the major factors behind vehicle accidents, and according to the 2009 GES data, improper lane changes, turns and merges (all of which are heavily influenced by the presence of blind spots), accounted for 6.3% of all large truck crashes. By the raw numbers, that’s 20,311 crashes in 2009 alone. Clearly, blind spots are causing wrecks.

And that’s only the beginning because according to the GES data, 2% of all fatal and incapacitating crashes in 2009 (or 165 total) were the result of blind spots, and 6.1% of all crashes involving an injury (or 1,426 total) were caused by blind spots, at least in part.

Both 18-wheelers and passenger vehicles have blind spots at the immediate rear of the vehicle, and every week in the U.S., around 50 children are hit by vehicles that are backed up over them, according to the Department of Transportation. Of those 50, 48 require hospitalization and two die as a result of their injuries. Among all types of non-traffic fatalities involving children, back-overs are the most prevalent, representing 34% of all child fatalities from 2006 to 2010. On average, 232 people of all ages are killed and 13,000 are injured every year due to backup injuries.

The Transportation Security Administration estimates that if every vehicle, including commercial trucks, were equipped with backup cameras, 100 lives would be saved and 7,000 injuries would be avoided every year.

Fortunately, tractor trailer cameras provide a realistic, economical solution for most drivers.

A Full View of the Road

Cameras are normally installed to directly mitigate a truck’s blind spots. These cameras are built to be weatherproof and can resist heavy shock and vibration forces. Modern camera models can handle up to 100g of shock and 15g of vibration force, which far exceeds the daily wear and tear a camera will be subjected to on the road. They are also small and unobtrusive enough to stay out of the way, so they won’t effect the operation of the vehicle or the trailer.

Each camera is tied to a small LCD monitor that is installed in the cab. From the monitors, drivers can adjust the camera’s aim, switch on a microphone built into the camera to pick up exterior audio, and switch on lights for a better view at night. It’s a simple system that drivers are able to adjust to quickly, as confirmed by the NHTSA’s 2011 report on the use of tractor trailer cameras.

A note on the NHTSA study’s methodology – the 2011 study on tractor trailer cameras focused on monitoring how truck drivers adjusted to the technology and whether or not the camera’s presence improved driver performance. To gauge the former, eye tracking technology was installed in the driver cab to detect where the driver was looking at all times. This is important in figuring out if the driver’s attention is being diverted by the camera displays to a dangerous degree.

There was almost no learning curve when handling a newly installed system, even though researchers believed that drivers would express more dangerous driving while getting used to the cameras. In fact, the NHTSA found that, on average, a driver’s probability of looking forward at the road at any one moment was 86% before the cameras were installed. After installation, the NHTSA concluded that the chances of a driver looking forward at any given moment was unchanged. In short, the presence of monitors in the cab does not act as a distraction.

In fact, though most truck drivers have used mirrors exclusively for years, even decades, the NHTSA found that drivers were able to pull visual data faster from monitors than from the mirrors they were accustomed to. Again, using the eye tracking technology, the NHTSA determined that, on average, a truck driver spent 1.16 seconds looking at a mirror with each glance, while they only spent .74 seconds on average looking at a monitor each time they did so. That may seem like a negligible difference, but the difference between reacting to an emerging traffic hazard and causing a wreck is often just tenths of a second.

Perhaps most encouragingly, though, the NHTSA discovered that drivers relied on their cameras during traffic maneuvers and conditions usually considered the most dangerous. For example, drivers looked at the monitors about 8% of the time when changing lanes to the left. When changing lanes to the right, drivers looked at their monitors about 20% of the time. Right lane changes are considered riskier because the passenger side blind spot is much larger. Based on these numbers, it’s fair to assume that drivers relied on their monitors for high-risk traffic maneuvers, and found them to be effective in providing information.

Also, trucks equipped with cameras appeared to be much more confident at night, when blind spots are at their worst. The NHTSA’s study found that without cameras in place, the way truck drivers changed lanes differed greatly from day to night. When dark, drivers allowed much more clearance during lane changes than during the day. When equipped with cameras, though, driver behavior did not change from day to night, suggesting that the monitors offered the equivalent of daytime visibility.

Security and Convenience

The NHTSA’s 2011 study makes a convincing case for installing tractor trailer cameras in blind spots, but even if traffic safety wasn’t a priority to most drivers, cameras would still be a viable addition to any truck.

The National Safety Council considers commercial truck drivers a target for hijacking attempts, as the vehicle can be used to facilitate other crimes without appearing suspicious. Among the National Safety Council’s recommendations is to install rear and side cameras when possible, as they can alert a driver to a dangerous situation, such as hijackers hiding behind the trailer once the truck is stopped. If a driver is the victim of a crime, the cameras can be used to help identify and track the assailants, helping a driver recoup any losses they suffer as a result of a crime.

One more thing to consider. While truck drivers are accustomed to getting in and out of tight spaces, cameras make it even easier. When every minute counts, quickly positioning the trailer at an unloading facility or even during parking can help a driver maximize the value of their route and save money.

18-wheelers are still the backbone of U.S. freight transport, but their size and limited visibility makes them difficult to handle, even in the most experienced hands. A camera and monitor system can eliminate those dangerous blind spots and help a truck driver operate their vehicle with confidence and greater care for others.