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Introduction This guide describes proper workstation setup, posture, and health and work habits for computer users. In addition, this guide contains electrical and mechanical safety information applicable to all HP products. Also available at http://www.hp.com/ergo.
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WARNING WARNING! There may be a risk of serious physical injuries from working at your computer workstation. Read and follow the recommendations in this Safety & Comfort Guide to minimize the risk of injury and to increase your comfort. Some studies have suggested that long periods of typing, improper workstation setup, incorrect work habits, stressful work conditions and relationships, or problems in your personal health may be linked to injuries.
Table of contents 1 Promoting a safe and comfortable work environment Important choices ..........................1 Take action for safety & comfort ..................2 Students and teachers ......................2 Key principles ............................3 Adjust ........................... 3 Move ............................ 3 Relax ............................ 3 Listen ...........................
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Supporting your forearms ....................21 Using a palm rest ....................... 22 Papers and books ..........................23 Minimizing your reach ......................23 Using a document holder ....................23 Phone ..............................24 4 Working in comfort Using a notebook computer ....................... 26 On the road ........................
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Mounting accessories ......................49 Ventilation .......................... 49 Water and moisture ......................49 Grounded (earthed) products .................... 49 Power sources ........................50 Accessibility ........................50 Voltage select switch ......................50 Internal battery ........................50 Power cords ........................50 Protective attachment plug ....................50 Extension cord ........................
Promoting a safe and comfortable work environment IMPORTANT Some scientists believe that working intensely, or for a long time in uncomfortable or unnatural positions, may pose risks, such as those mentioned in the WARNING at the beginning of this Guide. The information included in this Guide is designed to help you work more safely by recommending ways to work more comfortably and effectively.
be able to minimize fatigue and discomfort, and reduce the risk of resulting strains that some scientists believe can lead to injury. Whenever you use a computer, you make choices that can affect your comfort and potentially your safety. This is true whether you use a desktop keyboard and monitor in an office, notebook computer in a college dormitory, wireless keyboard on your lap, or handheld at the airport.
Key principles To promote safety and comfort, follow these principles whenever you use your computer. Adjust ● Adjust your body position and your work equipment. ● There is no one "right" position. Find your comfort zone, as described in this Guide, and when working at your computer, frequently adjust within this zone.
Listen ● Listen to your body. ● Pay attention to any tension, discomfort, or pain you may feel, and take immediate action to relieve Remember ● Exercise regularly and maintain general fitness; this will help your body withstand the rigors of sedentary work.
Finding your comfort zone A range of positions AVOID! ● Do not sit in one fixed posture all day. ● Avoid slouching forward. ● Be sure not to lean back too far. That afternoon slump Pay particular attention to adjusting your posture in the afternoon when you may tend to get fatigued. Vary your posture A range of positions...
Depending on your tasks, you may find a range of sitting and standing postures that are comfortable. Within your comfort zone, change postures often throughout the day. Rather than working in a single posture, find your comfort zone. Your comfort zone is a range of positions that is generally appropriate and comfortable for your given work situation.
Organizing your adjustments The order in which you make various adjustments to your body position and work area may vary depending on the adjustability of your furniture. For tips on how to order your adjustments, refer to the Organizing your adjustments on page 35 section.
Feet, knees, and legs AVOID! Avoid placing boxes or other items under your desk that limit your leg room. You should be able to pull yourself all the way up to your desk without interference. TIPS ● Walk Get up from your desk frequently and take brief walks. ●...
Providing enough leg room Be sure you have sufficient space under your work surface for your knees and legs. Avoid concentrated pressure points along the underside of your thigh near the knee and the back side of your lower leg. Stretch your legs and vary your leg posture throughout the day.
Back AVOID! If you get a new adjustable chair, or if you share a chair with someone else, do not assume the settings are properly set for you. Adjust often If your chair is adjustable, experiment with the adjustments to find numerous comfortable positions, then adjust the chair frequently.
Getting comfortable Always make sure your lower back is well-supported. Make sure it feels comfortable in the position in which you are working. Back...
Shoulders and elbows Relax Remember to relax, particularly in areas where muscle tension often builds, such as your neck and shoulders. To minimize muscle tension, your shoulders should be relaxed, not elevated or drooped (refer to the Supporting your forearms on page 21 section), and your elbows should be placed comfortably in relation to your keyboard height.
Forearms, wrists, and hands AVOID! Be sure not to rest your wrists on sharp edges. TIPS ● Split keyboards If you find it difficult to type with a comfortable, neutral wrist position, you may want to try a split keyboard. Be aware, however, that improper setup or posture while using a split keyboard can increase marked bending in your wrists.
RIGHT Maintain a comfortable, neutral wrist position. WRONG! Do not bend your wrists markedly inward. Do not anchor your wrists When typing, do not anchor or rest your wrists on your work surface, your thighs, or a palm rest (sometimes called a wrist rest). Resting your palms while typing may be harmful because it can cause you to bend and hold your wrists and fingers back.
Eyes TIPS ● Think about your blink While looking at your monitor, remember to blink. Although blinking your eyes is something you normally do without thinking, you may be blinking less often when using your computer (studies have indicated that, on average, people blink 1/3 as frequently at the computer). Blinking helps keep your eyes naturally protected and lubricated and helps prevent dryness, a common source of discomfort.
Arranging your work area Monitor AVOID! ● If you look at the monitor more than you look at paper documents, avoid placing your monitor to the side. ● Avoid compromising your posture to compensate for glare or reflections. ● Try to avoid bright light sources in your field of vision. For example, do not face an uncovered window during daylight hours.
Positioning the monitor You may find a range of monitor heights that allows your head to be balanced comfortably over your shoulders. Place the monitor directly in front of you (refer to the Papers and books on page 23 section). To determine a comfortable viewing distance, stretch your arm toward the monitor and notice the location of your knuckles.
If you wear bifocals, trifocals, or progressive addition lenses, do not position your monitor so high that you have to tilt your head back to view the screen. Eliminating glare and reflections on your monitor Take the time to eliminate glare and reflections. To control daylight, use blinds, shades, or drapes, or try other glare-reducing measures.
Keyboard and pointing device TIPS ● Switch hands To give your pointing hand a break, you can periodically control your mouse or trackball with the opposite hand (using the device's software to switch the button assignments). ● Listen to your body Let your body be your guide when you place your keyboard and pointing device.
WRONG! Do not position your keyboard and pointing device at different levels and distances. Using a keyboard tray comfortably If you use a keyboard tray, make sure it is wide enough to accommodate your pointing device, such as a mouse or trackball. Otherwise, you will probably place the mouse on your desktop, higher and farther away than the keyboard.
Arm supports and palm rest AVOID! Armrests should not cause you to: ● Elevate or droop your shoulders. ● Lean excessively onto one or both elbows. ● Extend your elbows out to the sides. ● Anchor your wrists, forearms, or elbows while typing. ●...
Another option is to use forearm supports only when pausing, allowing your forearms and hands to float freely while typing and pointing. In this case, the support is properly adjusted when it is slightly below your forearm typing position but close and available for pauses (such as when you are reading from the screen).
Papers and books Select a work surface or surfaces that are large enough to hold the computer equipment and any additional items required for your work. To help minimize eye fatigue, position any materials to which you frequently refer at about the same viewing distance. Minimizing your reach Arrange your frequently used papers, books, or other items to minimize the distance you reach for them.
Phone AVOID! Avoid using an attachment for the phone receiver (a rubber or foam "shoulder rest" or "shoulder cradle") if it requires you to bend your neck to the side to cradle your phone between your ear and shoulder, especially for long phone calls. Talking comfort Keep your head balanced comfortably over your shoulders when talking on the phone, especially for long periods of time.
Working in comfort Using a notebook computer TIPS ● Notebook comfort When you must work where proper seating or support may not be available, such as on airplanes or in wilderness areas, change your position often while working and take brief breaks more frequently.
Seeking comfort When working with a notebook computer, keep your shoulders and neck relaxed and your head balanced over your shoulders. If you must work with your notebook computer on your lap, place a support surface (your briefcase, a bed table, or a large book) under the computer. This will also raise the computer and may improve comfort.
Typing style AVOID! Avoid banging on the keys or using more force than the keys require. TIPS ● Keep it light If your typing is on the heavy side, teach yourself to lighten up. Press the keys more gently. ● "Hunt-and-peck"...
Reaching for keys and key combinations To reach keys that are not near your keyboard's home row, move your whole arm; avoid overstretching your fingers. When pressing two keys simultaneously, such as Ctrl+C or Alt+F, use two hands instead of contorting your hand and fingers to reach both keys. Typing style...
Pointing style AVOID! Avoid gripping or pinching your mouse tightly. TIPS ● Pointing comfort When using a mouse, trackball, or other pointing device, hold it loosely and click the buttons using a light touch. Keep your hand and fingers relaxed at all times - whether actively using or merely placing your hand on the device while pausing.
Adjusting software controls You can use the software control panel to adjust the properties of your pointing device. For example, to reduce or eliminate mouse-lifting, try increasing the cursor speed or acceleration settings. If you use a pointing device with your left hand, the software control panel will allow you to switch the button assignments for maximum comfort.
Using a keyboard on a sofa or bed AVOID! When using a keyboard on a bed or sofa: ● Avoid reclining too far or slouching forward over your outstretched legs. ● Avoid sitting completely still and working without breaks for long periods. Back comfort On a sofa, chair, or bed, it is especially important to support your whole back.
Taking breaks and varying your tasks AVOID! "Binge computing" When working on a deadline that is near at hand-for example, when cranking out a report for work or for a class assignment - avoid "binge computing," working intensely for long periods of time without a break.
Monitoring your health habits and exercise The comfort and safety of working at your computer can be affected by your general state of health. Studies have shown that a variety of health conditions may increase the risk of discomfort, muscle and joint disorders, or injuries.
Organizing your adjustments Be inventive Adjustable furniture designed for computer use may not always be available. However, you can use towels, pillows, blankets, and books in many ways, such as to: ● Raise the height of your chair. ● Create a footrest. ●...
From the ground up Seat height: you should be able to plant your feet firmly on the floor. Chair back angles and lower back support: your back should be well supported. Keyboard height: home row should be near your elbow height. Keyboard slope: wrists should be in a comfortable, neutral position.
From the top down Seat height: elbow height should be near your keyboard's home row. Footrest, if you need one. Support your back. Follow steps 2 through 8, in the previous section. From the top down...
Your safety & comfort checklist TIPS ● Double-check Periodically double-check your postures and habits using this checklist. If you've forgotten a tip or two, reread the previous sections of this guide. ● Listen to your body Any time you make changes to your tasks, work area, or posture, "listen" to your body. Its signals of comfort or discomfort will help you know whether your adjustments are right.
Shoulders, arms, wrists, and hands ● Are your shoulders relaxed? ● Are your hands, wrists, and forearms in their neutral comfort zone? ● If you use arm supports, are they adjusted so that your shoulders are relaxed and your wrists are in a comfortable, neutral position? ●...
Eyes ● Do you rest your eyes frequently by focusing on a distant point? ● Do you get your eyes examined regularly by a vision care specialist? ● Do you blink enough? ● If you wear bifocals, trifocals, or progressive addition lenses, do you avoid tilting your head back to see the monitor? ●...
Typing style ● Are you training yourself to lighten up when you find you are pounding on the keys? ● If you are not a touch typist, have you been taking typing lessons? ● Are you training your fingers to relax when you find them tense, including those not touching the keys and pointing device, as well as those actively typing and pointing? ●...
Keyboard and pointing device ● Is your keyboard positioned directly in front of you? ● Are your keyboard height and slope adjusted so that your wrists are in a comfortable, neutral position and your shoulders relaxed? ● If you are typing with the keyboard on your lap, are your shoulders relaxed and your wrists in a comfortable, neutral position? ●...
Monitor ● Is your monitor positioned in front of you and at a comfortable viewing distance, about arm's length? Or if you look at a paper document more than your monitor, is your document holder in front of you with your monitor to one side? ●...
Notebook computer ● Do you change postures frequently, seeking a balance between relaxed shoulders and a comfortable neck posture? ● Do you avoid resting your wrists on your thighs while typing? ● When using a keyboard on a couch or bed, do you avoid reclining too far to avoid neck fatigue? ●...
General prevention ● Do you take breaks and walk around briefly, at least once per hour? ● Do you exercise regularly? ● Periodically, do you take inventory of the stress in your life and change what is within your control to change? ●...
Electrical and mechanical safety information HP products are designed to operate safely when installed and used according to the product instructions and general safety practices. The guidelines included in this section explain the potential risks associated with computer operation and provide important safety practices designed to minimize these risks.
Product safety policy and general practice HP products operate safely when used according to their marked electrical ratings and product usage instructions. They should always be used in accordance with the requirements of local and regional building and wiring codes intended for the safe use of IT equipment. The IEC 60950 standards provide general safety design requirements that reduce the risk of personal injury to both the computer user and the service partner.
Installation requirements HP products operate safely when used according to their marked electrical ratings and product usage instructions. They should always be used in accordance with the requirements of local and regional building and wiring codes intended for the safe use of IT equipment. IMPORTANT: HP products are intended for use in dry or sheltered environments unless otherwise stated in the product information.
General precautions for HP products Retain the safety and operating instructions provided with the product for future reference. Follow all operating and usage instructions. Observe all warnings on the product and in the operating instructions. To reduce the risk of fire, bodily injury, and damage to the equipment, observe the following precautions. Damage requiring service Unplug the product from the electrical outlet and take the product to a service partner under the following conditions:...
Power sources The product should be operated only from the type of power source indicated on the product's electrical ratings label. If you have questions about the type of power source to use, contact your service partner or local power company. For a product that operates from battery power or other power sources, the operating instructions are included with the product.
Cleaning Unplug the product from the wall outlet before cleaning. Do not use liquid cleaners or aerosol cleaners. Use a damp cloth for cleaning. Heat The product should be placed away from radiators, heat registers, stoves, or other pieces of equipment (including amplifiers) that produce heat.
Precautions for portable computer products In addition to the general precautions described earlier, be sure to observe the following precautions when operating a portable computer product. Failure to observe these precautions could result in fire, bodily injury, and damage to the equipment. WARNING! To reduce the possibility of heat-related injuries or of overheating the computer, do not place the computer directly on your lap or obstruct the computer air vents.
Precautions for server and network products In addition to the general precautions described earlier, be sure to observe the following precautions when operating server and network products. Failure to observe these precautions could result in fire, bodily injury, and damage to the equipment. Safety interlocks and enclosures To prevent access to areas containing hazardous energy levels, some servers are provided with safety interlocks that disable the power supply when the enclosure cover is removed.
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● Do not extend the components from the rack too quickly as the moving weight may damage the supporting rails. ● Do not overload the AC supply branch circuit that provides power to the rack. The total rack load should not exceed 80% of the branch circuit rating. Chapter 7 Electrical and mechanical safety information...
Precautions for products with hot-pluggable power supplies Observe the following guidelines when connecting and disconnecting power to the power supplies: ● Install the power supply before connecting the power cord to the power supply. ● Unplug the power cord before removing the power supply from the server. ●...
Precautions for products with external television antenna connectors In addition to the general precautions described earlier, be sure to observe the following precautions when using external television antennas with your product. Failure to observe these precautions could result in fire, bodily injury, and damage to the equipment. Compatibility HP television tuner cards with antenna connections should be used only with HP personal computers that are intended for home use.
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Electric Service Equipment Power Service Grounding Electrode System (NEC Art 250, Part H) Ground Clamps Grounding Conductors (NEC Section 810-21) Antenna Discharge Unit (NEC Section 810-20) Ground Clamp Antenna Lead-in Wire Precautions for products with external television antenna connectors...
Precautions for products with modems, telecommunications, or local area network options In addition to the general precautions described earlier, be sure to observe the following precautions when operating telecommunications and network equipment. Failure to observe these precautions could result in fire, bodily injury, and damage to the equipment. ●...
Precautions for products with laser devices All HP systems equipped with a laser device comply with safety standards, including International Electrotechnical Commission (IEC) 60825 and its relevant national implementations. With specific regard to the laser, the equipment complies with laser product performance standards set by government agencies for a Class 1 laser product.
Symbols on equipment The following table contains safety icons that may appear on HP equipment. Refer to this table for an explanation of the icons, and heed the warnings that accompany them. This symbol, when used alone or in conjunction with any of the following icons, indicates the need to consult the operating instructions provided with the product.
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Any product or assembly marked with these symbols indicates that the component exceeds the recommended weight for one individual to handle safely. WARNING: To reduce the risk of personal injury or damage to the equipment, observe local occupational health and safety requirements and guidelines for manual material handling.
More information If you want more information about arrangement of work space and equipment or safety standards, refer American National Standards Institute (ANSI) 11 West 42nd St. New York, NY 10036 http://www.ansi.org Human Factors and Ergonomics Society (HFES) P.O. Box 1369 Santa Monica, CA 90406-1369 http://www.hfes.org International Electrotechnical Commission (IEC)
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http://www.cdc.gov/niosh Occupational Safety and Health Administration (OSHA) Publications Office U.S. Department of Labor 200 Constitution Ave. NW, Room N3101 Washington, DC 20210 http://www.osha.gov TCO Development Linnégatan 14 SE-114 94 Stockholm, Sweden http://www.tcodevelopment.com...