Preventing Injuries Associated with Uncoupling Trailers

Although it’s not a complex task, uncoupling a trailer incorrectly can yield devastating results. For that reason, individuals new to the trucking industry are trained to follow very specific procedures. In large part, the uncoupling procedures included in driver training are intended to guard against dropping a trailer on raised landing gear, pulling airlines loose; or incurring other forms of property damage.

What driver training often fails to stress is the damage that can occur to the driver’s own body. Drivers pulling fifth-wheel releases can sustain shoulder, neck and back injuries. In an article in Dynamic Chiropractic entitled, “Upper Extremity Injuries in the Trucking Industry“ the authors indicate that injuries incurred from pulling a fifth-wheel release are often manifested as rotator cuff damage, subluxations (misaligned vertebrae) or lateral epicondylitis (tennis elbow).

Because of the location of the fifth-wheel release handle, drivers who manually pull the fifth-wheel release by hand must stoop or squat; reach into the narrow area between the tractor frame and the trailer apron; and then pull hard enough to release the king-pin. The amount of force required to pull the fifth-wheel release handle depends upon a number of factors, to include the fifth-wheel type; the degree to which the fifth-wheel has been properly maintained; and the frequency at which it is used. The force required to pull the fifth-wheel release can also be dependent on the positional relationship between the tractor and the trailer. Particularly when the tractor and trailer are not perfectly aligned, increased tension can be placed on the fifth wheel assembly, making it more difficult (sometimes nearly impossible) to pull the fifth-wheel release handle.

 

This picture shows a driver reaching under a trailer to pull a fifth-wheel release. Notice that the driver is in a position that may increase the potential for injury (relying upon small muscle groups in the arm and shoulder for pulling). Additionally, in that position, the driver is unable to effectively use the weight of his body for mechanical advantage.

For this particular hazard, air-operated fifth-wheel unlocking systems represent an engineering control. These devises permit the driver to control the uncoupling process from inside the cab with little more manual effort than pressing a button. These systems are designed to work only when the tractor and trailer are not in motion and the parking brake is engaged. When functioning properly, these devises completely eliminate the injury exposure to the driver’s shoulder, neck and back from pulling the manual fifth-wheel release. As such, air-operated fifth-wheel unlocking systems represent the most effective and most desirable control for this hazard. They are available both as options on new equipment and asretrofit kits for standard (manual release) fifth wheels.
retrofit kits for standard (manual release) fifth wheels.

Another mechanical means of addressing this hazard are newly-designed fifth-wheels that require less pulling force than standard fifth-wheel models. At 65 lbs. of pull-force, Fontaine’s No Slack II^® boasts to be easier to engage and disengage than any fifth-wheel on the market. As these still require drivers to manually pull the fifth-wheel release, they reduce (but do not eliminate) exposure to such injuries.

In the next issue of Beyond the Cab, other control strategies for addressing this hazard will be addressed, including the use of fifth-wheel release pulling devises; proper positioning of the power unit; executing proper body mechanics; and an effective preventative maintenance program. The next issue of Beyond the Cab will also reveal the results of an online poll that seeks to learn the percentage of drivers who have (and use) fifth-wheel release pulling devises.

If you have further suggestions for controlling hazards associated with uncoupling trailers, we welcome your comments at losscontrol@midwesterninsurance.com. We also welcome comments on other non-driving hazards within the trucking industry and will post driver comments in future issues.

Copyright Ó2007 Midwestern Insurance Alliance

Midwestern Insurance Alliance, the exclusive workers’ compensation provider endorsed by the Kentucky Motor Transport Association (KMTA) and the Indiana Motor Truck Association (IMTA).