The topic of ergonomics is huge. It is far too large to cover in one, ten maybe even hundreds of articles. But the benefits of ergonomic-minded planning are too important to ignore. This article is intended to help savvy security professionals realize the value in careful considerations during planning, leading to more attentive operation, increased effectiveness and user comfort and safety.
The Range of Ergonomics
Ergonomics is a far broader topic than some typical definitions would indicate, such as this one from the Berkeley Lab: “Ergonomics is the science of designing the job, equipment, and workplace to fit the worker.” While clear and concise, this definition could easily be interpreted as focusing on the physical elements alone — “fitting the worker” in a physical sense. In truth, each of these elements is not just physical. Each one has broader implications, including psychological, cognitive and perceptual factors.
Factors for Ergonomic Consideration
Recognizing that many security installations are fundamentally similar to computer workstations, there are many recommendations available for how best to set them up.
The US Department of Labor, for example, via its Occupational Safety and Health Administration (OSHA), promotes ergonomic considerations specifically for computer workstations. Their evaluation checklists have sections for these elements:
• Working Postures
• Seating
• Keyboard/Input Device
• Monitor
• Work Area
• Accessories
• General
The only downside of this and similar checklists and recommendations may be that they are too limited. That is, that they reinforce the idea that the physical ergonomic elements by themselves are enough to consider.
Despite that focus, there’s no question that checklists and recommendations like these are a positive step. They can not only help setting up workstations in a way that reduces a full range of possible strains and injuries, but they also help to educate a wider group of people about the importance of ergonomic considerations in the purchasing, setting up, training and operation of workstations and workstation-based tasks.
If the field of ergonomics is actually very wide as well as complex and deep enough to often require a master’s degree, what do security executives need to know?
In short, this:
1. Ergonomics is very important, and will affect user operation. Whether it helps it or hurts it is up to you.
2. Ergonomics has relatively observable physical elements that can be planned for and adjusted in operation to minimize negative effects.
3. Ergonomics also includes perceptual and psychological elements that are more subtle, but could well be just as important to your results as the physical elements.
A Closer Look: The Ergonomics of Monitors
The monitor is the primary source of information to the workstation user. Whether it is a monitoring station, front desk or badging station, the monitor tells the user what is happening, what action can be taken and what information is available for making decisions.
Monitor Ergonomic Recommendations: Checklists often recommend positioning the worker in the chair and desk before addressing the positioning of the monitor.
The size and shape of the human determines the basics — chair height, knee height, reach and similar factors. The position and arrangement of the chair, desk and keyboard or other input devices depends first on the size of the human that will be using them. Arranging a monitor before setting the seat height will not result in an optimal arrangement.
Once the chair and desk are adjusted, then we can address the position of the monitor itself. Eye Level or Below? While many published checklists reflect the current ‘conventional wisdom’ that the monitor should be positioned directly in front of the worker, at a height such that the top of the monitor is at or slightly below eye level when sitting upright, some in the field question whether this is correct. Some cite research indicating that the normal viewing angle is lower and that mounting monitors lower would be better for overall performance.
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.
Consider this — a worker is seated comfortably, facing forward with a monitor slightly below eye level, with no reflected glare on the screen, at an arm’s length from the monitor. If the monitor resolution is insufficient to display the necessary data clearly, then no amount of eye straining, leaning forward or other actions will let that worker be effective.
Making the Right Choice
Ergonomic factors include important physical elements, but a more complete system view also includes perceptual and cognitive elements. Security executives that are planning or contemplating new installations can improve the effectiveness of those installations by taking care to consider ergonomic issues in the planning stages.
The physical elements of ergonomics can be addressed by including these factors in the physical design and purchase process. For example, choosing security furniture with adequate under-desk clearance, adjustable chairs and flexible monitor mounting will go a long way toward meeting the range of positioning that will accommodate most users.
Working with a vendor that has software that includes real room dimensions, obstructions, windows and doors will remove more surprises and help to avoid situations where adjustments will hamper workers’ effectiveness.
And lastly, make sure that any planning takes into account the type and style of displayed content to be sure that the resolution, number and position of the displays will be sufficient to enable workers to act effectively.
This story was submitted by Middle Atlantic Products (www.MiddleAtlantic.com), a manufacturer of racks and enclosures, surveillance and monitoring console, data and cabling management, studio furniture, video mounts and power products.
