You Asked for It
January 2004

Question about laptop computers in cars:

I was wondering if you had any information or had done any evaluations of work areas of workers who use their vehicle as an office. I am interested in your comments on the position of the laptop and keyboard. Most times I would think workers are going to be in an awkward position.

I would appreciate your comments.

Grace
Alberta Government

Response:

(The response to Grace’s question has been provided by Mike Harnett of WorkSmart Injury Prevention Systems, mharnett@worksmart.ab.ca, 780-414-6436)

Part One: The Vehicle as an Office - Laptop Ergonomics

Vehicles have become offices on wheels for a number of workers, ranging from emergency services personnel to field servicing in the oil patch to real estate agents. Laptops in general have a number of ergonomic risk factors that we would not normally find with the more traditional personal computer stations. Add them into a vehicle, and you've just magnified the problems.

There are four main types of computer systems being used in vehicles,

1. Standard laptops that are simply used on the lap and transported in and out of the vehicle.
2. Laptops that slide into a mounted docking station that can then be used in or out of the vehicle.
3. Laptops that are affixed to stationary, rotating or adjustable hardware for use in the vehicle only.
4. Fixed monitors with detachable keyboards, which allows the employee to position the keyboard on their lap. The monitor is typically fixed to the dash or mounting device.

The integration and installation of any of these systems into a vehicle involves many challenges. Space on the dash or console is required to accommodate any mounting hardware. Sometimes it will take up valuable driver or passenger space, thus compromising their postures even when not using the device. Depending upon where they are mounted, they can impede the function of an airbag. Worse, they can become a projectile thrown by the force of the airbag. An unsecured device (un-mounted laptop) may also become a safety hazard during a hard brake, turn, or collision.

In addition to these safety issues, ergonomic complications arise when you actually try to use the device.

If the device is being used infrequently (less than 10% of their total workday), then the risk is significantly lower for the development of problems, compared to a device that is used occasionally (11% - 33%) or frequently (34% - 66%). So, first we need to determine how often the device is going to be accessed or referred to.

Next, we need to examine the primary ergonomic risk factors,

• Force – not a major concern (unless the person types like a concert pianist!)
• Repetition – can become a concern depending on how frequently the device is being utilized
• Posture – BINGO! As so often emphasized, the main concern is posture. Awkward and static postures held for even a few seconds at a time can irritate the tissues.

Let’s take a look at how these risk factors translate into pain and discomfort for various body segments when using a laptop in a vehicle.

Back/Neck Concerns
The primary concern is the back and neck, which are subject to an increased risk of injury simply by being in a vehicle. With the addition of laptops, we are often trapping employees in their vehicles for even longer periods of time, further impairing blood flow and nutrition to the soft tissues of the legs and back. In the wintertime it is not unusual to have the worker sit in a running vehicle for warmth, increasing the vibration factor on the spine. Now, add in twisting of the back to access the keyboard, twisting of the neck for viewing, or simply leaning to the side where the laptop is located, and it’s a recipe for disaster.

Risk to the neck can be affected whether you're a one-finger typist (commonly referred to as a hunt and peck typist) or a touch-typist. Touch-typing will require less viewing of the keys and as a result, less neck flexion and eye accommodation, unlike the hunt and peck typer who will be constantly shifting their gaze between the keys and monitor. If the operator also has to twist his head to view the screen, this repetitive action can result in problems. However, the touch typist is no better off if they have to hold their neck twisted to one side in an attempt to improve viewing.

Shoulder/Upper Back Concerns
If the laptop is mounted and the keyboard is not detachable, we often find the touch typist twisting and compressing one shoulder against the backrest of their chair while the other arm stretches across the body to access the keyboard. This is less of a problem for a hunt and peck typist who uses only one hand.

If the mounting hardware allows for adjusting the height of the laptop, most people will elevate the device for better viewing. Unfortunately, if the program they use is primarily controlled through a touch pad or pointing device located on the laptop, they end up having to hold up the weight of the entire arm in a static position, thereby taxing the shoulder’s muscles, tendons, and bursa.

Even after adjusting for height, viewing is often impaired due to glare from sunlight, oncoming traffic lights, or interior cab lights. Older workers will be more affected by these factors. Additionally, the smaller screen size can affect resolution and font size, further increasing the demand on one’s eyes. If a person can’t see the information on the screen, then they will adjust the head and neck away from the neutral posture, simply to improve the view. This can translate into headaches, neck, shoulder and upper back discomfort.

Elbow/Wrist/Hand Concerns
Keyboard designs for mounted laptops are often smaller (smaller keys, tighter spacing) to accommodate for reduced space in the vehicle cab. The downside is that most men already have difficulty with a standard laptop keyboard. Reducing it further can result in a number of errors and frustrations for the worker, as well as an increase in wrist deviation and extension.

In addition, most computer systems that are operated in vehicles have a touch pad or small pointing device on the keyboard in place of a full-size mouse. Once again, the result is frustration for many individuals and fatigue in the small muscles groups that are being used to control the cursor.

If you’re left handed, chances are that unless you have the laptop or keyboard resting on your lap, you will have to assume more stressful postures to reach over your body to the keyboard or pointing device that is typically mounted on the right side of the driver.

If the keyboard is resting on the lap…well, try moving your office keyboard onto your lap and see how much your wrists have to extend. You won’t be able to type for long before the pain creeps in. You’ll also notice that your shoulders are probably riding up around your ears to lessen the strain, thus transferring the problem back up the body.

Don’t forget, winter conditions means that workers are often using the laptop while their hands are cold, increasing their risk for circulation problems and subsequent musculoskeletal disorders.

It comes down to this; the more risk factors that are present, the greater likelihood for discomfort and the development of an injury. As businesses continues to decentralize, the race is on to see who can develop the most user-friendly and safe portable computer for your vehicle, but we're a long way from the finish line!

Part Two: The Vehicle as an Office – Strategies to Improve Laptop Ergonomics

Last month you had a crash course in what risk factors to watch out for when operating a laptop in a vehicle. Now, let’s talk about some strategies to reduce those risks.

• First and foremost, the purpose of the computer has to be assessed. Maybe a laptop isn’t really required. Can they get away with using a PDA (Personal Data Assistant) or handheld computer such as a Palm Pilot or Blackberry? They’re certainly cheaper and more ergonomically friendly in a vehicle setting.
• If a laptop is required, a docking station allows for the most flexibility. Drivers will most likely have to use the laptop while it is mounted in the station due to the steering column and general lack of space on their side, while passengers have the option of removing the laptop and placing it on their lap.
• Invest in a docking station that allows for maximum adjustability (height, distance, and screen angle positions).
• Hardware and software that allows for touch screen activation may reduce or eliminate the need for a keyboard or pointing device in some instances.
• Train the employees in how to use shortcut keys with their software program to reduce the number of repetitions and the amount of time spent in an awkward posture.
• Police officers in the United States have recently been piloting voice-activated software with great success. Depending upon the software requirements you have, this may be a viable option.
• In many instances, the programs used in vehicles are mapping programs, utilizing mostly the touch pad or pointing device. Having an external, full-size and wireless mouse that can be propped up on an armrest, briefcase etc. will discourage static reaching of the arm to access the touch pad on the keyboard, especially if up on docking station.
• Consider fully integrated laptop units that can tie GPS navigation and multimedia with the vehicle’s current audio system. Alternatively, you may have to deal with a number of cables and attachments, which further restrict space and might also require awkward postures to disconnect and reconnect every time the laptop is removed/returned to the vehicle.
• Many individuals who work out of their vehicle also have a regular office, and transport their laptop between the two. In this scenario, it is extremely important to have a docking station in the office for the laptop where they have access to a full-size monitor, keyboard and external mouse. The goal is to minimize the overall time spent using the laptop, since the risk factors are greater than a regular set-up.
• Just like an indoor office environment, every once in a while we have to get up and move. This is even more important when our office is a vehicle, subject to road vibration, potholes, or poor lumbar support. Exit the vehicle on a regular basis to increase circulation and nutrition to the discs in the back, as well as blood flow to the extremities.
• If you have the option, take the laptop out of the vehicle and sit down in a cafe, on a bench, or anywhere that allows you to sit directly in front of the device, and input your data. With the height of most work trucks these days, some workers prefer to place the laptop on their tailgate and operate it while standing up. While it may be more comfortable for the back and upper extremities, the neck may get sore after a while, so be sure to give it a break every once in a while.
• Avoid awkward or static postures. If this isn’t possible (and I’ve yet to see a laptop that didn’t require an awkward posture), put your body back in balance by stretching out the opposing muscle groups on a regular basis. Remember, your muscles work in pairs and if you’re always twisting or leaning to one side to access the laptop, one group of muscles is being over stretched while the opposite group is cramping up. Both groups are now susceptible to pain and injury.
  
  Don’t wait until you actually feel pain to start changing your habits. Have someone take a picture of you while operating the laptop in the vehicle. Look at the position of your head, shoulders, upper back, lower back and legs. Then, try some stretches that take your body in the opposite direction.

A final word on safety...you should NEVER operate a laptop or keyboard in a moving vehicle. It takes away from viewing the road and your eyes may not accommodate fast enough to changing conditions in front or behind you. Pull over into a parking lot or safe area away from roadside traffic to access the laptop. This will also reduce the chances of someone rear-ending you, deploying the airbags, and catapulting the laptop into your body.

Operating a laptop in a vehicle has many risks attached to it. Make sure you carefully evaluate for those risks, and then minimize as many as you can to optimize your comfort and safety!

Mike Harnett
WorkSmart Injury Prevention Systems
2nd Floor, 3304 Parsons Road
Edmonton, AB T6N 1B5
780-414-6436
mharnett@worksmart.ab.ca

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