Ergonomics — a science that concerns the relationship between workers and their machines, began during World War II with attempts to design cockpits that made pilots efficient and comfortable. Its principles moved into the factory, and then, when computers became commonplace, into the office.
Today, providing a properly equipped work environment is an important priority for companies that rely on computers for designing products and manufacturing systems. At stake is the health and productivity of engineers and designers. The sedentary nature of dedicated computer work, the fast work pace of the engineering office, and the long work hours can take a toll. Musculoskeletal strain and stress-related ailments can cause absenteeism, insurance claims, and even legal recourse.
By applying ergonomics, you can boost the productivity of the engineering staff, improve morale, reduce absenteeism, and lower medical costs. All it takes is careful planning, asking the right questions, judicious purchasing, and common sense.
Observe and ask
Start by reviewing your present computer work environment. Are lighting, temperature, and ventilation adequate? Are connections to power and communications adequate and accessible? Do the computer operators have suitable work surfaces and storage for manuals, catalogs, references, and supplies? How does work flow through your office? How closely must engineers and designers work together? How important is interpersonal communication?
Three steps can help you assess your needs: observe and evaluate the work environment, review maintenance records, and talk to the computer operators. To evaluate the environment, prepare a checklist based on requirements listed in the preceding paragraph, adding others as needed. Answer as many of the questions as you can based on observation and personal knowledge. Then review maintenance records, which may disclose problems in areas such as lighting, temperature levels, ventilation, and electrical requirements. Finally, discuss working conditions with the computer operators to gain insights into their satisfaction levels with work flow, equipment, and workplace comfort. These discussions can generate suggestions about improving their productivity through new equipment and workplace amenities.
Recent changes (or planned changes) in computer hardware can have an impact on the workplace. Larger PCs or workstations, monitors, printers, and other peripherals may crowd the area. Networking with other engineers or with the factory floor may require modifications to the area.
Lighting
Lighting engineers have found that standard office lighting is too bright for the computer environment. For example, suggested levels for typical office work range from 50 to 100 footcandles (fc).
In the computer area, however, suggested levels range from 25 to 75 fc. Overhead lighting and natural light creates reflected glare from computer screens, which causes distractions and eyestrain, as well as head and neck pain, thereby increasing the likelihood of errors.
Here are some steps to reduce lighting and glare problems:
• Reduce overhead light by removing fluorescent tubes, replacing them with lower output tubes, or installing louvers in overhead lighting units.
• Provide adjustable task lights to illuminate source documents rather than the monitor screen.
• Add a glare screen or hood to the monitor.
• Angle the monitor slightly down or to the side.
• Position computer workstations parallel to or away from windows.
• Position workstations between lighting sources.
• Install window blinds or shades.
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Temperature control
Improper temperature and inadequate ventilation are the most frequent environmental complaints and among the toughest to handle, according to facility managers. Furthermore, air quality complaints have risen as some companies lowered air exchange rates below ASHRAE (American Society of Heating, Refrigeration, and Air Conditioning Engineers) recommendations in order to save energy. When laying out your computer area, keep in mind that computer equipment and peripherals generate heat. To improve ventilation and temperature conditions:
• Have cooling and heating systems, including ductwork, periodically cleaned and inspected.
• Adjust the number of air exchanges per hour to comply with ASHRAE and EPA standards.
• Don’t place computer workstations under or in front of vents.
• Consider buying computer furniture modules with built-in ventilation units, or supplement the building system with local air filtration units. These units can range from desktop devices to large mobile units using clean-room filtration technology.
Electrical power
Even in buildings with uninterruptible power systems (UPS), workstations need further power protection because electrical power can contain damaging voltage spikes (surges). Though some workstation furniture has built-in surge protection, most do not. Surge protectors, ranging in price from $10 to more than $100, are easy to install. Be sure you understand the difference between surge protection, line conditioning, and UPS. They are all related, but differ in the type of protection they offer. Here are some guidelines in choosing surge protection for your computers:
• Carefully choose surge protectors and isolation transformers, making sure that they protect your equipment from surges, spikes, and brownouts.
• Select a protector with picosecond or nanosecond response to clamp off surges in trillionths or billionths of a second, respectively.
• Make sure the volt peak clamping performance is rated at no more than 400 V. The lower a unit is rated, the more effectively it operates.
• Check the joule rating. Greater joule dissipation capacity numbers mean more efficient and durable protection.
• Choose a unit with an alarm and a light to indicate depletion.
• Look for a unit with an Underwriter’s Laboratory listing of 1449. Units with ULlisted components may not be UL listed for complete units.
Furniture
Matching computer furniture to your operators’ needs will enhance their productivity, safety, and comfort. The computer’s function should determine the size, shape, and construction of the furniture. Consider these factors:
• Computer furniture is available in freestanding and modular forms. If flexibility is important, freestanding units may be the right choice. Panel-hung modular units provide privacy and they buffer noise, but are generally unsuitable for large PCs or workstations used for CAD/CAM.
• Someone must assemble and install the furniture. Many units are sold readyto- assemble, but office furniture dealers can usually handle the task for you.
• Particleboard or injection-molded plastic units are not as strong or durable as wood or steel-framed units. Laminates usually provide an easily maintained, durable surface.
• Your supplier should be able to deliver additional components quickly. And they should be easy to install.
• Consider what your operators need in work surface, storage, and accessories. Very tall or short workers and disabled workers should have adjustable work surfaces that allow them to work seated or standing. Storage should be within reach. Consider items such as adjustable monitor supports, keyboard trays, and pull-out mouse trays. A left-handed operator may have difficulty using a desk with a righthand return or a standard mouse mounting configuration.
• Wire channels keep cabling out of sight and prevent possible injuries. Some furniture includes plug-in baseboards or work surfaces.
Seating
The chair is the most critical factor in ensuring an operator’s comfort and productivity. When work surfaces are fixed, the chair must be adjustable to eliminate any physical disparity between operator and keyboard. Here are some guidelines:
• Selecting a chair without a trial is a gamble. Some furniture dealers provide samples.
• Look for a waterfall-edge seat, a fivefooted star base, plus seat and back adjustments that are easy to use.
• Teach users to properly adjust chairs.
• When selecting a chair with arms, make sure it provides enough clearance so a user can get close to the work without colliding. Forearms should rest naturally on the chair’s arms.
• Upholstery should be static resistant. Padding should be firm, not mushy.
• Lower lumbar support should be firm, not hard.
• Prices can range from $200 to $1,000 for an “ergonomic” chair. Comfort and support, not price, are the best indicators of a good chair.
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AccessoriesWorkstation accessories can make the difference between comfort and discomfort, and hence, errors and productivity. Some noteworthy accessories include: |