In some cases, recommendations note that for those that use reading glasses, or in those designs that require workers to look over the top edge of nearby monitors to occasionally review larger monitors that are mounted farther away, that the nearby monitors be mounted significantly lower than eye level.
Eyes Front, Face Front: Another key recommendation in many lists is that the monitor should be directly in front of the worker, to see the content on the monitor without twisting the neck to either side (“neutral position”). Choosing monitor mounts for security installations that have a good range of positioning is a smart way to accommodate a range of users and operating positions.
Competitive pressures and the increasing sophistication of the monitoring software have pushed many installations to have multiple screens for each user, sometimes making it impossible to follow this guidance exactly. Mounts supporting multiple monitors can be adjusted to place a primary monitor directly in front of a worker, with adjunct monitors to one or each side, or above, if the situation allows it.
One solution is to put the highest priority or primary monitoring activity on the central monitor directly in front of the worker, and to put lower priority information to the sides. If the system has the capability, managers might consider setting the system so that the current activity or that which demands the most current attention move to the center of the viewing area so that the worker is in the least stressful position when working on that activity.
Lighting Considerations: Another visibility factor that appears on many checklists is to consider the sources and direction of lighting. It is suggested that glare on the screen can be minimized by positioning monitors “at right angles to the sources of the light” and to close blinds and shades.
If monitors need this repositioning in this way, it will affect the arrangement of the furniture in the room. To plan security installations effectively, security executives should be sure that any plans or layouts indicate major sources of light, including windows, doorways and primary light fixtures. Look for a vendor that has software that can show the positions of these items if possible to avoid surprises.
Viewing Distance: The last common item usually found on these ergonomic recommendation lists for monitor placement is the distance from the user. The recommendations cover a fairly wide range of distance — from “about an arm’s length away” (Microsoft) to “at a comfortable viewing distance, approximately 18-30 inches from the viewer” (CDC).
Some more detailed sources, such as the useful short articles posted by the State Compensation Insurance Fund (SCIF), are even more pragmatic. They point out that worker preferences vary due to many reasons, and that therefore the best approach is to determine your own comfortable viewing distance — and then they describe a simple procedure for doing so.
Bottom Line — Still Not Sufficient
For individual workers, the SCIF approach might be the most useful guidance. For system designers, however, it remains a challenge to build enough flexibility into the installation to accommodate the expected range of worker needs. The guidance in these lists is missing some key considerations, and the actionable direction that will ensure the installation will meet the many different ergonomic needs of the workers.
What is missing? Note that none of these recommendations focuses directly on the content that is to be viewed. Security executives should be aware of the type of content that is planned for an installation and take steps to ensure that the content will be displayed in a way that workers will easily understand and be able to act on.
Ergonomic Success Requires a System View
It is simply not possible to implement a complete ergonomic solution by using only the physical elements of the system without considering the system view.
The design of the display content itself, including type (text, charts, images, etc.) format and layout, resolution, colors and other details are critical factors for worker effectiveness that cannot be ignored without affecting — and possibly negating — all the other positive physical steps taken earlier.