Archive for Agustus 2014
Laser printers can causes problems to your health. The sources of possible health concerns are : toner, ozone, light and ultraviolet light, noise, and heat.
Laser Printer
A. Toner
Laser printers use toner as part of the printing process. The toner is an extremely fine powder, which in itself is not classed as a substance hazardous to health, but any dust in substantial concentration is, as it may cause respiratory tract irritation resulting in coughing and sneezing.
Toner dust is considered a nuisance dust and should have no health effects other than those noted above. However, persons who have an already compromised respiratory system (e.g. suffer from asthma, bronchitis, etc) should avoid changing toner cartridges. If this is not practicable then the operation should be carried out with extreme caution to avoid generating a dust cloud.
B. Ozone
Ozone, O3, a form of oxygen, is a normal constituent of the earth’s atmosphere. It is a highly reactive, unstable, colourless gas with a distinctive odour which, at room temperature, decomposes rapidly to oxygen, O2, particularly on contact with furnishings. Ozone cannot be stored or transported in vessels because it decomposes in the presence of oxidisible impurities, humidity and solid surfaces.
As ozone is such a highly reactive substance, any adverse health effects will be found essentially at the sites of initial contact; the respiratory tract (nose, throat and airways), the lungs and at higher concentrations, the eyes. The principle health affects are produced by irritation of and damage to the small airways of the lung and at very high concentrations can have serious adverse health effects such as nausea and pulmonary congestion.
C. Light and Ultraviolet Light
The lamps in photocopiers emit light in both the visible and ultraviolet ranges. In general, the ultraviolet light does not pass beyond the glass plate in which the original is placed. Estimated operator exposure to visible light is minimal and is well below the permissible exposure level.
Nevertheless, as an additional safety measure, keep the cover closed whilst copying. Should the cover have to remain partially open , e.g. to copy a book, look away from the light source.
D. Noise
Exposure to high levels of noise is common in the printing industry and can cause temporary or permanent hearing loss. Temporary hearing loss can result from short-term exposures to noise, with normal hearing returning after a period of rest. Permanent hearing loss can also result depending on the nature of the noise. Noise induced hearing loss is preventable through controls that are aimed at eliminating or reducing noise at the source, along the pathor at the worker.
E. Heat
Heat production vary considerably according to the printer. Heat are fatiguing, distracting and stressful . Heat production in the room can be dispersed by good room ventilation, air conditioning or dedicated extract ventilation.
Solutions/Tips:
- Make sure the office is well-ventilated with air from outside
- If possible, locate heavily-used printers in well-ventilated areas, away from people
- Avoid standing over the printer as it prints
- If you are sitting next to a heavily-used printer, consider asking for you or the printer to move
- People with asthma or heart disease would be best advised not to sit near busy printers
SOURCES:
Thx
Many people these days sit at a computer for a long period of time. By not sitting with a correct posture, you can easily end up with back pain, neck pain, knee pains, and a tingling of the hands and fingers.
This is a comfortable sitting posture which your joints are naturally aligned. Working with the body in a neutral sitting position reduces stress and strain on the muscles.
1. Head
Keep your head and neck aligned with your shoulders. Your monitor should be at below eye level. Generally your head should be in line with your torso. Your shoulders should be relaxed.
2. Back
Sit back in your chair so that you back is fully supported with appropriate lumbar support.
3. Hand.
Hand, wrists, and forearms are straight, in-line and parallel to the floor. Elbows stay in close and are bent between 90 and 120 degrees.
4. Thigh and Hips
Push you hips as far as the can go so they can touch the back of the seat. Thigh and hips should be supported to be a well-padded seat and generally parallel to the floor.
5. Knee
Bend you knees minimum at 90 degrees. The distance between the edge of the seat and the back of your knee is minimum 3 fingers.
6. Feet
Your feet should be flat on the floor. If your feet doesn't reach the floor, use footrests.
Regardless of how good your working posture is, working in the same posture or sitting still for prolonged periods is not healthy. You should change your working position frequently throughout the day in the following ways:
- Make small adjustments to your chair or backrest.
- Stretch your fingers, hands, arms, and torso
- Stand up and walk around for a few minutes periodically.
References: a. OSHA Ergonomics
Office Ergonomics Keyboard, Mouse and Monitor
Today, many of us rely on computers to do our work.
It is important to properly position your keyboard, mouse and monitor, so that you can work comfortably and avoid neck and vision problems.
1. Keyboard and Mouse
There are numerous keyboard and mouse configurations and models available, however it is important to correctly position these tools to prevent overuse injuries.
To properly position your keyboard and mouse, follow these steps:
- Sit close to the keyboard and mouse so that your upper arms hang in a relaxed position.
- Center yourself so that you are aligned with both the keyboard and mouse, depending on what is most frequently used. Position the mouse as close as possible to the keyboard to avoid rotating the shoulder.
- Adjust the height of the keyboard platform (or chair if there is not an adjustable platform), so that your shoulders are relaxed and elbow angle is 90 degrees or slightly greater.
- Adjust the angle of the keyboard platform slightly downward in a negative tilt, if able. This will help to keep your wrists straight.
- Do not put the mouse where you must stretch to the desk or out to the side of a keyboard to reach it.
- Your wrist should be straight while mousing, not angled toward your thumb or little finger.
Tips to limit overuse and awkward postures:
- Move the mouse from the elbow, rather than from the wrist down.
- Alternate mousing between left and right hands. Mouse buttons can be reconfigured to allow either hand to be used.
- Rest your finger lightly on the mouse button, do not hold it hovering above the mouse.
- Do not grip the mouse tightly - hold it gently and glide it over the surface.
- Choose a mouse that fits your hand, and that can be used with either hand.
- Use shortcut keys whenever possible to limit mouse use.
- If you are correctly positioned, a wrist rest should not be necessary. However, when a neutral wrist posture cannot be achieved or to reduce contact with hard surfaces, a wrist rest may be helpful. Do not plant your wrists on the pad while keying or mousing. Make sure the wrist rest is made of a soft gel or foam to minimize pressure on the underside of the wrist.
- Key with gentle, quick keystrokes. Do not pounds on keys as this increases the force exerted.
- You can position the mouse over the numeric keypad with an articulating mouse platform or mouse "bridge".
- When mousing is a constant requirement (e.g. CAD applications), the forearm should be supported on a surface or with an adjustable armrest to reduce static loading of the arm.
- Alternative keyboards and mousing devices are available to accommodate for specific needs.
2. Monitor
You need to position your monitor properly to avoid neck and eye problems.
Steps:
- The monitor should be positioned so that your natural gaze falls about one-third down the length of the screen.
- The distance should be about arm's length (45 to 60 cm). Font size, specific applications and personal visual acuity and sensitivity will also determine the correct distance, however placing the monitor too far away can cause the user to lean forward and can lead to eyestrain.
- Bifocal users should lower the monitor so that text can be viewed through the proper prescription. Increasing the distance away from you also increases the field of vision available without moving the head. Tilting the screen upward slightly can also help.
- The monitor should be directly in front you, aligned with the area of the keyboard that you use most.
- Adjust contrast and brightness to your personal needs to reduce eyestrain.
- Look away from your screen periodically - focus on a distant object to exercise eye muscles.
In using tables and chairs for working or using computers, you need the ones that's good for your health.
TABLES
Tables required should have:
- Adjustable height. The top of your work surface should be at your elbow height.
- Monitor arms. The monitor should be positioned directly in front of you with the top of the monitor just below eye level.
- Footrests. If your work surface can't be lowered or raised to accommodate your elbow height, you can raise your chair and use a footrest. The footrest should be large enough for both feet.
- Keyboard tray. Can be used to bring the keyboard and mouse to elbow height. Should be height and tilt adjustable.
- Wide space. Materials used frequently should be located within easy reach. By keeping materials you do not use frequently out of reach, you will have to get out of your chair for them. This will promote blood circulation and reduce overall discomfort.
- Document holders.
CHAIRS
Some basic pointers in choosing a good chair:
