Transcript Document
Office Ergonomics/Safety Pamela A. Boatright System Safety, Health & Environment Resource Center Oklahoma State Regents for Higher Education Ergonomic Regulations OSHA published a draft ergonomic standard, but it was not approved. However, the OSHA “General Duty Clause” requires employers to provide a safe and healthy working environment for employees. OSRHE Guidelines (4/98) Ergonomics The study of the relationship between man and machine. When the body is required to perform repetitive motion, work in an awkward position, or repeatedly lift heavy objects, injuries may develop. When employees are comfortable they are more productive. Risk Factors Repetitive activity Holding a position without movement Use of force or strength Localized pressure Awkward positions (Low temperature) (Vibration) Repetitive Activity Open letters Stapling Flipping through files Sorting letters Keyboard Computer vs. typewriter Holding Position w/o Movement Reduces blood flow Fatigue Work demands Gripping mouse too tightly Holding phone to ear Excessive Use of Force Typist – up to 10,000 impacts per day People diagnosed with carpal tunnel use 18% more force to do a task Excessive Use of Force Stapling Stamping Grasping large folders or books Lifting files/books Pushing/pulling heavy file drawer Chair “scooting” Localized Pressure Sharp edges Keyboard corners Work surface corners Hard or angular chair arm rests Awkward Positions Press on nerves, stretch tendons Shoulder and phone Elbow and phone Poor neck postures, movements Leaning, reaching for tools (10-key, printer, stapler, etc.) Awkward Positions, Wrist Bending up, down, side-to-side Inappropriate keyboard height Inappropriate keyboard angle No support for resting hands Splayed elbows Faulty keyboarding/mouse habits Neutral Body Posture Places the least amount of stress on the body Physical stress is evenly distributed “Zero gravity posture” “Neutral position” Neutral Body Posture Straight back 90° hip bend 90° knee bend Straight head/neck Relaxed shoulders 90° elbow bend Straight wrists Upright sitting posture The torso and neck are approximately vertical and in-line The thighs are approximately horizontal The lower legs are vertical Declined sitting posture Thighs are inclined The angle between the thighs and the torso is greater than 90 degrees. Torso is vertical or slightly reclined and the legs are vertical. Standing posture The legs, torso, neck, and head are approximately in-line and vertical. The user may also elevate one foot on a rest while in this posture. MSDs Carpal Tunnel Guyon’s Canal Epicondylitis Reynaud’s Thoraic Outlet Muscle Strains Ganglion Cysts Tendonitis Tenosynovitis DeQuervain’s Trigger Finger Back Pain Carpal Tunnel The channel found in the wrist surrounded by bones and a non-elastic ligament. Several blood vessels, nine tendons, and the median nerve all pass through this channel from the forearm into the hand. Carpal Tunnel Certain movements, especially repeated movements and bent wrists, can cause an increase in pressure in the carpal tunnel. Symptoms can include tingling, numbness, pain, swelling, and burning sensation in the hand. 1-2 per 1000 Workstation Configuration Workstation Configuration Chair Characteristics Keyboard and Mouse Monitor Position Glare Document Position Telephone Use Work Behavior Chairs Chair Position Back straight Head upright Fully supported S-curve in spine Wrists straight Hips, knees and elbows at 90° Feet and arms supported Examples of Good Chairs Chair Characteristics Back rest covers from hip to upper back Contoured and padded seat and backrest Waterfall seat design Five casters for stability Chair Adjustability Seat height Seat depth Tilt tension Back height Arm height see slide out card under chairs, left forward side Examples of Poor Chairs Bad and Ugly Too! Keyboards/Point Devices Keyboard and Mouse Position About 2-3” lower than desk height If you can’t lower the keyboard, you may consider raising your chair. Center the alphabetical section to your body. Keep the keyboard flat. Rest wrists on rest pad only when not typing. Place the mouse next to the keyboard. Keyboard Positioning Place the keyboard directly in front of you at a distance that allows your elbows to stay close to your body with your forearms approximately parallel with the floor. A keyboard tray may be useful if you have limited desk space or if your chair has armrests that interfere with adequate positioning. Wrist Rest Placement Your hands should move freely and be elevated above the wrist/palm rest while typing. When resting, the pad should contact the heel or palm of your hand, not your wrist. Wrist Rest Placement Some desks and computer equipment have hard, angled leading edges. This can affect nerves and blood vessels, possibly causing tingling and sore fingers. Typical Keyboards/Trays Keyboard Tray Tilt 0° to -15° No + tilt angle Height Adjusts 6 1/4“ Base Swivel Locks Alternative Keyboards Keyboard Placement Alternative keyboards help maintain neutral wrist postures, but available research does not provide conclusive evidence that using these keyboards prevents discomfort or injury. Pointing Devices Improper Mouse Placement Mouse Wrist Rest Alternative Pointing Devices Good Working Positions | Workstation Components Checklists | Adjusting Computer Pointer Sensitivity and speed should feel comfortable. The pointer should be able to cover the full screen while the wrist is maintained in a straight, neutral posture. Sensitivity should be set so you can control the pointing device with a light touch. Most devices can be adjusted through the computer control panel. Avoid tightly gripping the mouse or pointing device. Monitor Position Monitor Position Monitor in front of the keyboard, not to side Top of monitor at eye level Arm’s length away (24-30” approx.) Up to 10° backward tilt or flat Text size may need to be increased for smaller monitors. Monitor Position The top of the monitor should be at or slightly below eye level. The center of the computer monitor should normally be located 15 to 20 degrees below horizontal eye level Monitor Position Monitor blocks are simple and inexpensive. Telephone books are cheaper. Monitor Position Bifocal Wearers Bifocal users typically view the monitor through the bottom portion of their lenses. This causes them to tilt the head backward to see a monitor that may otherwise be appropriately placed. As with a monitor that is too high, this can fatigue muscles that support the head. Monitor Tilt Monitors that are tilted significantly either toward or away from the operator may distort objects on the screen, making them difficult to read. When the monitor is tilted back, overhead lights may create glare on the screen. This can result in eyestrain and sitting in awkward postures to avoid eye glare. Monitor Solutions Lower the monitor so you can maintain appropriate neck postures. You may need to tilt the monitor screen up. Raise chair height until you can view the monitor without tilting your head back. You may have to raise the keyboard and use a foot rest. Use a pair of single-vision lenses designed for computer work. Other Monitor Considerations Adjust brightness as needed. Keep the screen clean. Glare Glare Glare may cause eye strain or headaches. Position the monitor between overhead lights and perpendicular to windows Select a glare screen for the model and size of monitor, but only if needed. Task lighting on the document should not cause glare on the monitor. EMF “radiation” is NOT an issue. Glare screens Block up to 99.9% of ELF/VLF E-field radiation when properly grounded $250 Glare only $130 Document Holders Document Position Position documents next to monitor and at the same height to reduce: Head and neck movement Eye refocusing distance Document Holder Allows you to place documents at or about the same height and distance as the monitor screen. Should be stable when loaded with heavier documents such as a textbook. Provides a sturdy writing surface, if written entries are necessary. Work Zones Work Zones The location of frequently-used items should remain within the primary work zone. Telephone Use Telephone Use Place the telephone in the primary or secondary work zone, depending on usage patterns. Cradling the telephone between your neck and shoulder creates an awkward position. Avoid the shoulder-rest device if at all possible. Consider a phone headset instead. Telephone Quick Tips Use a speaker phone or head set for long conversations. Keep it close enough to avoid repeated reaching. Work Behavior Eye relaxation techniques Change tasks and/or position every 20 - 30 minutes. Place palms over closed eyes and relax Focus on far away objects - “20/20 Rule” Allows muscles to recuperate from static positioning Improves blood flow to extremities Microbreaks (do NOT replace regular breaks) Work Behavior High repetition tasks or jobs that require long periods of static posture may require several, short rest breaks. Users should stand, stretch, and move around to provides rest and this allows the muscles to recover. Alternate tasks whenever possible, mixing non-computer-related tasks into the workday. This encourages body movement and the use of different muscle groups. Lift CAREFULLY; never twist and lift Workstation Assessments Workstation Assessment Limited space on the work surface may cause users to place components and devices in undesirable positions. Workstation Assessment No room for trackball on keyboard tray No document holder No wrist rest Workstation Assessment Monitor too low Mouse position Keyboard position No arm rests Document holder good Workstation Assessment Poor mouse position No document holder Workstation Assessment Monitor and keyboard too high No arm support Document height too low Workstation Assessment Much better !! Lowered monitor Raised arm rests Raised chair Conclusion All you need is common sense. Always work in neutral positions. Modify the equipment around you, don’t modify your body posture to fit the equipment. Give adjustments a couple of days. Minimize awkward postures, static positioning, and repetitive movements. Workstation Stretches Developed by Dr. Houshand Seradge, M.D. The Hand Institute Orthopaedic & Reconstructive Center 1044 SW 44th Street Oklahoma City, OK 73109 405/631-4263 Laptop Ergonomic Guidelines Centers for Disease Control and Prevention Laptop Guidelines The CDC recommends that laptop computers not be used as a primary computer at home or at work. Occasional users should: Find a comfortable chair Use a neutral wrist position Position screen to minimize neck bending Laptop Guidelines Consider using an external keyboard or docking station. Take mini-breaks ever 20-30 minutes. Keep viewing distance @18-30 inches. Position keyboard at elbow height. If seated in a side-chair or couch, use a pillow to support your arms while keying. Clean the screen regularly. Docking Stations Transporting the Computer If computer and accessories > 10 lbs, consider a bag with wheels. Eliminate all unnecessary items from your briefcase. Carry a laptop in a case with padded shoulder pad and handle. Shift hands and shoulders to balance the load. Web Resources http://www.osha.gov/SLTC/etools/comp uterworkstations/index.html http://www.osha.gov/SLTC/etools/comp uterworkstations/positions.html http://www.osha.gov/SLTC/etools/comp uterworkstations/checklist.html http://www.osha.gov/SLTC/etools/comp uterworkstations/wkstation_enviro.html Office Safety Falls Falls are the most common office accident. Clear walking pathway Close drawers after use Avoid bending, twisting, leaning while seated Secure electrical cords Struck By or Striking Objects Bumping into desks, cabinets, open drawers Supplies falling out of cabinets or off shelves Misbalanced file cabinets Machines dropped on feet Doors opening suddenly Caught In or Between Fingers caught in drawer, door, or window Fingers, hair, clothing, jewelry caught in machines Fingers caught under knife or paper cutter Safe Office Practices Use a proper stepladder for overhead reaching, not rolling chairs or even padded chairs, please. Clean up spills immediately, even if they are not “yours”. Report loose carpeting, damaged flooring, lights out, etc. Office Electrical Safety Never remove the grounding plug from any piece of equipment. Inspect electrical equipment and electrical cords regularly. Repair or discard if damaged. Electrical Cords Do not drape or pull over nails, hooks, or other sharp objects. Extension cords are temporary wiring only. If a cord must run across a walkway, tape it or cover it. Never pull a plug to turn off equipment. Electrical Cords Working on “live” equipment Disconnect electrical machines before cleaning or adjusting. If a guard is removed to clean or repair parts, replace the guard before testing or putting it back in service. “Daisy Chain” Slip, trip, or fall Electrical Cords Overloaded Outlets