We are all familiar with drug testing rules and Department of Transportation (DOT) regulations meant to promote safety on the roads, but employers cannot ignore other safety concerns such as the ergonomics of a driver's vehicle. Individuals who spend a significant amount of time in a vehicle may develop a repetitive motion injury such as lower back pain, carpal tunnel syndrome, sore and/or stiff neck and shoulders, and foot and leg cramps.
These injuries can be the result of several different factors, not least of which is that it is often difficult to get up and move around when your occupation requires you to spend long hours on the road. Over time, things such as maintaining awkward or poor static posture (whether from a seat that is not well designed or simply from habit), gripping the steering wheel too tightly, and the low-frequency vibrations caused by a moving car or truck can all lead to injury, decreased productivity, and early retirement.
For this reason, it is important that a vehicle is fit to a driver's specific shape, size, and individual needs.
What are Ergonomic Aids?
Ergonomic aids are tools designed for a specific work environment that help an employee maintain a neutral position throughout the day. These tools should be tailored to the employee's size, lifestyle, age, as well as any preexisting conditions. In the case of drivers, proper ergonomics will maximize the body’s natural ability to move and respond to stressors while in the vehicle. (Learn more in "8 Key Areas of Ergonomics Employers Must Consider").
8 Important Ergonomic Aids for Drivers
Any person who spends more than 20 hours per week in a vehicle has an increased risk of developing a work-related musculoskeletal disorder. The tools listed below can help ensure proper positioning throughout the day, thereby preventing costly long-term injuries and increasing overall productivity of your employees.
Adjustable Lumbar Support
The presence of proper, adjustable lumbar support in a vehicle has been associated with less discomfort among drivers. For best results, the seat back needs to be about shoulder height, wide enough to support the full back, and adjustable both up-and-down as well as in-and-out (from the seat reference point). Ideally, a driver's back should be in full contact with the back rest (no gaps or pressure points should be present). Furthermore, the seat should be set to a slight recline so that there is an approximate angle of about 100 to 110 degrees between a driver's back and thighs. If the adjustable controls do not allow for a proper fit, provide the driver with a lumbar pillow.
Adjustable Cushioned Seats
Just as the seat back needs to be supportive for long drives, the seat itself should also be comfortable and cushioned and support the entire length of a driver's thighs. A quick test to ensure that the seat is the correct size is to measure the distance between the back of the driver's knee and the front of the seat. The space should equal about 2 to 3 fingers held together. Lumbar pillows can help shorter drivers achieve a proper fit.
Drivers should be able to see at least 7.6 cm (3 inches) over the steering wheel in order to have a clear view out the window. However, it is also important that there is enough headroom so that driver does not have to slouch.
In addition, there should be about 25 to 35 cm (10 to 12 inches) between the chest and the center of the steering wheel so that airbags and seat belt are safe in case of a crash. To achieve proper positioning for each driver, the seat should be fully adjustable. This means that the height, tilt of cushion and seat back, and the distance between the seat and steering wheel can all be customized. The ideal amount of tilt in a seat depends on the height and needs of a driver. While taller drivers may want to elevate the tilt, drivers who use the clutch often may want to lower it. In either case, a coccyx cushion can help improve seat tilt and open up hip flexors of drivers.
Another important aspect of the seat fit is the head rest, also known as a head restraint due to the fact that it protects the head in case of a rear-end collision by restricting movement.
This portion of the seat should also be fully adjustable in both up-and-down as well as forward-and-back directions. A head rest is in the proper position when the top is between the driver’s ears and the top of his/her head, and the driver’s head is as close to the restraint as possible (no more than 7 to 10 cm away).
Finally, it is important that the head rest be locked into position after adjustments are made in order to prevent whiplash in the case of a crash.
Adjustable Shoulder Belt
For safety (and legal) reasons, all drivers should be required to wear their seat belts at all times while operating a vehicle. It is important that the shoulder belt is adjustable up-and-down to accommodate drivers of different heights, ensuring maximum safety and comfort. The shoulder belt is at the correct height when it rests on the middle of the collar bone. Drivers who are in need of additional comfort, or have special requirements like a medical port that needs to be protected, should be provided with a shoulder strap cushion.
Adjustable Steering Wheel
A vehicle's steering wheel should not interfere with leg movement while a driver is pressing the pedals or getting in and out of the vehicle. In addition, it needs to be within easy reach and close enough that the driver's arms remain slightly bent while operating the vehicle.
For these reasons, the wheel should be fully adjustable in all directions: up and down, forward and back, as well as the tilt. For those drivers who are on the road for extended periods of time, power steering requires less effort and can prevent strain.
Another aspect of the vehicle that can potentially be adjustable are the pedals. Vehicles that allow for the position of the break, accelerator, and clutch pedals to accommodate the different leg lengths of a variety drivers provide increased comfort. However, if the pedals are adjustable, it is important that they also have a retractor safety system in place so that a driver's feet are not caught between the pedals and the floor.
Running Boards or Extra Steps
Sometimes vehicles are so tall that getting in and out of them requires a driver to overextend or jump. Unfortunately, jumping down from a large vehicle to the ground over time can cause the spine to compress, increasing the risk of injury. This can be prevented by adding an extra step or a running board to tall vehicles.
In addition, it is important to make sure that any straps and door handles that might assist a driver with getting in and out of the vehicle are easy to grab and free from wear and tear.
Temperature Control Systems
While it is particularly important to keep windows free of frost to maintain good vision in cold temperatures, the environment within the vehicle should be kept comfortable in all types of weather. Good temperatures can be maintained through proper heating, air conditioning, and ventilation controls. As an added benefit, low noise levels can make driving less stressful.
Fitting a vehicle to a specific driver can keep your employees healthy and on the road. However, while the tools listed above are important, they are only one part of the solution.
It is also essential to encourage drivers to take regular rest and stretch breaks whenever possible, ideally about about once an hour. In addition, drivers should try to arrange their schedules so that they alternate between long and short driving days, especially if they are driving at night. (Learn more in "Fatigue Management in Night Shift Workers and Employer Risks"). This gives the body a chance to recover from time on the road and helps reduce the risk of future injury.