Safe Working with Display Screen Equipment - Workplace Ergonomics

Transcription

1 Safe Working with Display Screen Equipment - Workplace Ergonomics Ergonomics refers to the interaction of people with their work and surrounding environment. It is concerned with ensuring a good fit between the employee and his/her work. This includes a variety of issues such as overall workplace design, the layout of workstations and signage. Consideration of ergonomics becomes important in the day-to-day prevention of musculoskeletal problems and Upper Limb Disorders including RSI, as poor ergonomic layout and posture can put strain on muscles and joints. The principles of ergonomics apply to all employees and all workplaces. In the Fairley House School (FHS) environment, you should make full use of the adjustment facilities for your VDU and work environment to get the best from them and avoid potential health problems. Adjust your chair and VDU to find the most comfortable position for your work. Make sure there is enough space underneath your desk to move your legs freely. Move any obstacles such as boxes or equipment, as they can prevent freedom of motion and create trip hazards. It is unlikely that any member of the academic staff need spend more than one hour continuously in front of a screen, but there may be occasions, such as report writing, when this occurs. So the following paragraphs should help you to maintain your health. On completion of your self assessment if you identify any issues the Health and Safety Consultant will assess your workstation with you to identify potential hazards and then take measures to avoid or minimize risks of injury and ill health. In addition to the School s assessment, employees should: Avoid excess pressure on the backs of your legs and knees. A footrest, particularly for smaller users, may be helpful. Don't sit in the same position for long periods. Make sure you change your posture as often as practicable. Some movement is desirable, but avoid repeated stretching movements, such as reaching for files or the phone. Adjust your keyboard and screen to get a good keying and viewing position. A space in front of the keyboard is helpful for resting the hands and wrists while not keying. Don't bend your hands up at the wrist when keying. Try to keep a soft touch on the keys and don't overstretch your fingers. If a keyboard is equipped with feet at the back, flip them into the Down position to avoid extra angulations of the wrists. Good keyboard technique is important.

2 Try different layouts of keyboard, screen and document holder to find the best arrangement for you. Make sure you have enough workspace to take whatever documents you need. A document holder may help you to avoid awkward neck movements. Arrange your desk and screen so that bright lights are not reflected in the screen. You shouldn't be directly facing windows or bright lights. Adjust curtains or blinds to prevent unwanted light. Make sure the characters on your screen are sharply focussed and can be read easily. They shouldn't flicker or move. Make sure there are no layers of dirt, grime or finger marks on the screen. General example of good desk posture: Display Screen Equipment and Eyestrain Eyestrain can be experienced as burning, tightness, sharp pains, dull pains, watering, blurring, double vision, headaches, and other sensations, depending on the person. If you have any eye discomfort caused by viewing something, you can call it eyestrain. In VDU workstations, the principal factors affecting the ability to see well are: Glare Luminescence difference; the difference between the brightness of the screen and the surrounding area The amount of light Distance between the eye, screen and the document Readability of the screen and document Your vision and the use of corrective lenses What You Should Know Try to eliminate direct glare. Direct glare involves a light source shining

3 directly into the eyes, for example from ceiling lights, task lights, or bright windows. To determine the degree of direct glare, you can temporarily shield your eyes with a hand and notice whether you feel immediate relief. Reflected glare, such as on computer screens, sometimes causes eyestrain. But its worst effect may be causing you to change your posture to an uncomfortable one, in order to see well. The most overlooked cause of eyestrain in offices is contrast, usually a dark screen surrounded by a bright background such as a window or a lit wall. The best solution is to find a way to darken the area around the screen. This problem occurs mainly on screens with light letters on a black background. Use the brightness control on the screen to suit the lighting conditions in the room. There should be plenty of light for easy reading, but too much can, depending on the person, cause eyestrain. How much light is right depends on your age, the quality of the print you're reading, and other factors. Eyes are strained more by close viewing than by distant viewing. The "right" distance for computer monitors and documents depends on how clearly they can be read at a given distance. The general rule is to keep viewed material as far away as possible, provided it can be read easily. If you gaze at something too long, your eyes can tire. Eyes need to focus at different distances from time to time. It's a good idea to follow the "20/20 rule" - every twenty minutes, look twenty feet away for twenty seconds. If two objects are only a couple of inches different in their distance from the eyes, the eyes actually do not have to refocus to look from one to another. Greater distance differences, however, can overwork the eyes if you have to look from one object to another frequently, as when typing from printed copy and looking at the screen. In general, keep viewed objects at about the same distance if you have to look back and forth. According to optometrists, rarely can computer work cause nearsightedness. It's more likely that computer work makes you realize that you need glasses. Sometimes eyestrain is just a case of dry eyes. Lowering the monitor can help. Looking downward means more of the eye surface is covered by the eyelid, and two other things happen: the eyes unconsciously blink more, and they produce more lubrication. As a broad guide, your eyes should be at the same height as the top of the VDU casing. Fairley House School encourages all employees to: Take a five minute break from the computer every hour Take the full lunch break away from their desks Keep computer monitors clean and free of dirt or fingerprints Adjust the brightness and the contrast to suit the room lighting conditions Ensure that the characters or images on the screen do not flicker Report problems with visual display equipment immediately so that any

4 problems can be rectified When practical, people who need bifocals should consider other options besides bifocals. Bifocal wearers often experience sore necks and shoulders because they have to tip their heads back to see the computer screen. Alternatives are: Computer glasses that focus at the right distance to the computer screen Wearing contact lenses corrected for computer or reading distance in one eye, and far distance (if needed) for the other. Lower the monitor as much as possible, Lower the work surface if possible Eye Examinations: FHS employees are entitled to an annual eye examination. Employees must retain the invoice from the eye examination, and present it to The Bursar who will arrange for reimbursement. Repetitive Strain Injury (RSI) Repetitive strain injury (RSI) is an overuse injury that is one of the family of injuries known as Work Related Upper Limb Disorders (WRULD's) or Cumulative Trauma Disorders (CTDs). Repetitive action can affect people who use a computer, but many hobbies and sports also involve repetitive motion. RSI problems are not limited to only the upper body; they can also affect the spine or legs. Because of the complexity and subtle differences between disorders, physicians don't always diagnose RSI's correctly or easily. WRULD's can have serious consequences if not actively prevented or if detected, not acted on promptly. Most RSI's are preventable and curable if caught early. The key is to notice trouble when it starts and do something about it. The signs may be constant or may occur after performing certain activities. The drastic cures - such as surgery - are not reliable and should be a last resort. Nevertheless, a health professional should be consulted when you are concerned about possible early signs. Symptoms of WRULD's and RSI are variable, but there are symptoms that should not be ignored. These symptoms are: Pain in the hands or wrists Pain in the forearms Alteration in sensation; dullness or numbness Feelings of weakness in the hands or fingers Tingling or pins and needles in the hands, forearms or shoulder regions Difficulty in bending or straightening the fingers

5 The risks of WRULD and RSI are higher when the following factors are present: Continual repetitive actions Long hours at the computer Insufficient recovery period Incorrect set up of workstation Bad posture Poor physical conditioning Some people can get RSI's because their bodies are vulnerable to them. For example, carpal tunnel syndrome seems to be related to diabetes, overweight, thyroid conditions, hormone conditions such as those caused by hysterectomy, rheumatoid arthritis, and previous injuries such as whiplash. Smoking may also increase the risk. Anyone with any of these conditions - particularly obesity - should be especially careful about prevention! Although physical workstation design and adjustability are important, there are many other work-related factors. Three less tangible but extremely important factors are job design, stress control, and individual work style. Examples of job design are infrequent or inflexible breaks, low activity variety, and fast pace. Stressors are deadlines, monitoring, and bad management. Harmful work styles (in the context of computer work, for instance) are how hard you hit keys, how you hold your wrists, and where you place the mouse. In addition to any specific control measures identified by risk assessments employees are encouraged (as far as possible) to: Always ensure your workstation is set up well in accordance with instructions and training received and that you review the set-up periodically If you are uncomfortable, this may be a sign that either your desk, chair or computer set up needs to be re-evaluated Get up and move frequently. Stretch for short periods frequently throughout the day. Research has shown that muscles respond to stretching on a small regular basis, rather than one-off episodes. Make sure you have enough room to move around. Do not allow a cluttered workplace to restrict your movement or force you into an uncomfortable posture. Vary your work activities throughout the day to allow for movement and change in posture. Create forced breaks by placing your printer, copier, and fax in places where you have to move to get to them. Adjust the swivel or tilt position of the computer monitor to suit individual characteristics such as height Do not overstretch when using the keyboard or mouse Use soft-touch typing techniques Arrange the desk and screen so that reflected light from windows and other sources is minimised. Stay fit. Regular exercise provides many benefits, but it also helps the

6 muscles of the torso to stay stronger, which in turn gives support to the spine and the upper body RSI, if it develops, can be eradicated but quick identification and treatment is very important. Report symptoms to the Health and Safety manager and see your GP. A risk assessment for your workstation may need to be repeated. Work Workouts Prolonged sitting or static positions can create pressure on the spine and tension in the muscles. Stretching throughout the day can relieve compression on the spine; muscle aches and can improve circulation. Studies have shown that even short stretches performed frequently over the day can decrease musculoskeletal discomfort by 50% and were more effective than longer stretching episodes performed at less frequent intervals. Make sure you get up at frequent intervals. Make sure that you stretch frequently while standing. Remember that pressure on the lower spine in sitting is significantly higher than in a standing position. Guidelines: Never bounce when stretching Relax while stretching and breathe Feel a stretch but not a pain Spend about 10 seconds per stretch, longer periods are even better

7