DESIGNING HEALTHY AND PRODUCTIVE OFFICES By the turn of the century, industry will spend 50 cents out of every dollar on medical costs for cumulative trauma injuries. According to the U.S. Bureau of Statistics: repetitive strain injuries accounted for 18% of all workplace injury claims before 1981. By 1981, the percentage increased to 51%, and in 1990 it increased to 56%. What do these percentages reveal? Remember, 1981 was the year the PC was introduced, and by 1990 more than 40 million users were sitting in front of terminals. Over the past 20 years, office procedures have changed dramatically. The advent of automated systems and support media has led to major capital investments in computer equipment and software. Because of these expenditures, assurance that the company’s systems are running smoothly is high on management’s priority list. Additional monies are spent to protect against power spikes and outages. Backing up is critical to protect against a total data loss through a catastrophic crash; so again, capital expenditure is the rule. A crash may be caused by a system failure or by a virus that wreaks havoc with hard drives. The latter problem generates the need for additional software that analyzes and repairs virus- infected files. In each instance, equipment and data take priority. Because of these systems, most businesses have benefited from in- creased productivity and profits. But with the new systems and work procedures come new health-related problems among workers. Statistics show that this once overlooked problem is now of major concern to both employers and employees. WHAT IS ERGONOMICS? Ergonomics is an applied science that coordinates the design of devices, systems, and physical working conditions with the capacities and requirements of the worker. Another term used is “human engineering.” Ergonomics puts the human element in the work environment, which is made up of several basic elements such as lighting, air quality, and work area placement and design. With improper management of these critical areas, workers can suffer, causing stress and affecting productivity. The study of ergonomics is a prime factor in drawing attention to all the health issues in the office. Through an ergonomic approach and evaluation of these issues, work area design–including lighting and furniture–can be optimized to assist in reducing stress and increasing productivity. WORKPLACE CONCERNS Employers and employees have common interest in several areas of concern. Health, safety, and legal issues can and will arise with consequences that affect everyone in the long term. With too much stress, whether physiological or psychological, lost work time results in the form of sick leave or reduced efficiency. Increased medical claims and litigation are the results of these problems. These issues have been of concern to both employer and employee for health and legal aspects and, since the introduction of computers to the workplace, new concerns in this area have surfaced. Safety is always important, and increased computer usage brings increased exposure to potential hazards. These hazards often are difficult to define or recognize. Ergonomics helps define, locate and offer solutions to these problems, and thus benefits employers and employees. The insurance industry is an active participant in the ergonomic arena. Increased claims, both legal and medical, affect insurers’ profitability. To circumvent this, your premiums are increased. The insurance industry takes a keen interest in ergonomics and its impact on the workforce. One large carrier has a full-time ergonomic research team studying new work methods. They then train management and workers in these latest techniques in safe and stress- reducing work conditions. BACK PROBLEMS Statistics show that more than 80% of the general population suf- fers from some sort of back ailment. Incorrect posture can be caused by several factors at the workstation. Seating height, width and depth, display support height and clearance under the work area all contribute to the overall posture while working. People have a tendency to adjust or self-correct stressful problems by changing positions, resting, or moving. This explains why people who have a variety of activities during the day have lower incidence of RSI. Working at a computer terminal lends itself to a constrained sed- entary posture which leads to muscle fatigue, circulation loss in the lower extremities and stress on joints. There does not seem to be one specific causative area, but a combination of situations that can lead to neck, shoulder and back discomfort at a computer terminal. Research aimed at identifying and defining these situations is ongoing. Several studies have arrived at minimal recommended spec- ifications to afford the least amount of stress while seated. One such source is the American National Standards Institute (ANSI). ANSI has published a guideline, “American National Standard for Human Factors Engineering of Visual Display Terminal Workstations,” that outlines requirements, design, and layout of work areas and furniture. Keep in mind that ANSI is not an official testing agency, but issues guidelines based on published research find- ings. Some recommendations the institute has established for minimum work area comfort are: * Clearance under work surfaces: Minimum width for leg clear- ance is 20 to 24 inches. The ideal height should be, at minimum, equivalent to the highest point on the seated thigh or knee. * Display support surfaces: The display should be at a height between zero and 60 degrees below the horizontal plane of the eyes. * Work surface width and depth: Total area depends on the task, but should be capable of supporting all of the components needed to perform the task and any task support items. Even when all these criteria are met, other steps should be taken to prevent or reduce stress. As with RSI being related to key- stroke-intensive tasks, that same work task will lend itself to back and lower extremity problems. Timed breaks are a necessary part of data entry work. Exercises that are designed to relieve strained areas are also a viable part of the total solution. LIGHTING A factor often overlooked in eyestrain problems is lighting and glare. Studies have shown that workers rate good lighting as the single most important aspect of the office environment. This is followed by air quality and comfortable chairs. Improper lighting is sometimes difficult to discern. You immediately recognize very low or very bright settings, but marginal lighting (enough light to see your work but maybe not see it well) may not be perceived as a problem. Bright fluorescent lights over and behind the user cause reflections on the monitor face that make it difficult to read; this results in eyestrain and headaches. Often the monitor, and not the lighting, is blamed. With the monitor face being slightly convex, trouble- some reflections can come from wide angles to the screen. Also, the common practice of tilting the monitor back increases the in- cidence of reflections from ceiling fixtures. There are two glare problems to deal with, direct and indirect. Direct glare comes from line-of-sight light sources such as lights or windows. Since terminal users are looking forward instead of down at their desks, direct glare light sources are evident to them. Indirect glare, or reflection, is probably the most common problem for terminal users. Indirect glare is caused by light from bright objects, such as light fixtures, reflecting from smooth or glossy surfaces. Monitors can have either a specular or a diffuse reflection. Specular reflections are mirror-like sharp images reflected from the monitor back into the users’ faces. Diffuse reflections are reflections from light that penetrates the monitor’s glass surface and is reflected off of the phosphor layer behind the glass. Since the phosphor is somewhat rough, no sharp or defined image appears brighter with the effect of washing out the image. The type of light fixtures used in an office is a factor in the amount of direct glare that is present. Overhead lighting fixtures (called luminaires) are a common source of direct glare. Light fixtures that are low and in the line of sight are glare-producing sources. Often windows will be left unshielded to supplement ambient lighting or to offer a view. For the VDT user the sunshine just presents another glare source. A comfortable light level is important for all office workers re- gardless of whether they work at a computer. A good balance is hard to achieve but can be done with planning. AIR QUALITY Office air quality can be a major contributor in lost time and increased sick days. Indoor air affects the body in several ways: the nose detects odors; mucus membranes are affected by changes in humidity; airborne pollen can aggravate allergies. Air pollutants can cause colds, allergy attacks. sinus problems and headaches. The Sick Building Syndrome occurs when the concentration of pollutants and/or the interaction between pollutants causes temporary illness among occupants. Common complaints of Sick Building Syndrome are headaches, fatigue and membrane irritation. These symptoms are relieved when the person leaves the building. Building-Related Illness (BRI) concerns infections or diseases caused by bio-aerosols that find favorable growth conditions in the building environment. The bio-aerosols are fungi, bacteria, and viruses that flourish in carpeting, furnishings, and air-handling systems. Unlike Sick Building Syndrome-related illness, BRI’s usually require medical treatment. These problems are not a result of the age of the building but more so of the ventilation, air changeover, pollution-causing equipment (such as blueprint machines, some copiers), and the people themselves. The two basic standards used to specify, control, and evaluate indoor air quality are: * Prescriptive criteria, describing acceptable system through- out, such as ventilation rates, is used primarily during building design stage to determine system capacity needs. * Performance criteria, describing acceptable conditions within occupied spaces, such as temperature and humidity conditions based on scientific findings, are used for system evaluation and control after construction.
