Computer Health and Safety

1. The desktop should be arranged in a way to enable frequently used materials to be close to the user in order to refrain from excessive stretches to reach for things beyond arm length.
2. A matte finish work surface is recommended, as this will reduce glare and reflection.
3. There should be enough room underneath the desk. The space should provide ample room, and be free of clutter or any obstruction to knee, thigh and the stretching of the legs.
4. Vertically adjusted keyboard tray should be provided in case the table is a fixed height table.
5. Footrest should be placed under the table to support the feet In case the foot is not resting flat on the ground after adjusting the chair’s height.
6. Constant and frequent use of phone with computer such as call centre staff can cause discomfort to the shoulder or neck pain. This could be avoided with the use of headset or speakerphone.
7. Computer table lamp if available should be positioned so that it light up source documents and not causing glare on the computer screen or direct light to the user’s eyes.
8. A stable and adjustable document holder should be used if documents are being referred to during typing. The document holder should be at the same distance from the eye and the screen. This will prevent constant change of focus and also enable exchanging glances from the document folder and the screen without frequent movement of the neck and back.

4.        CHAIR

Seating on an unsuitable chair for computer purpose for a prolong period of time can increase pressure on the lower part of the back. Appropriate computer chair must be stable, comfortable and fits the user. Here are some following suggestions in order to help to increase the comfort of using computer:

Figure 2 RECOMMEDED CHAIR

Courtesy of the Workers’ Compensation Board of British Columbia.

1. Stability: A five point base chair should be used instead of four-point base as it provides more stability.
2. Seat and Padding: The chair seat cover should be absorbent and breathable. Unpadded seat becomes uncomfortable to seat on after a long while and could results in pain in your bottom and hip muscles.
3. Back Support: The computer chair must have a lumbar support and computer user must make use of the backrest to support the entire back and not perch on the chair. The height and the chair tilt should be adjusted to make sure the back is supported by the tilt.
4. Legroom: Whist sitting on the chair, provision for leg clearance of minimum 15” at the knees and 24” at the feet should be made available at all seated computer workstation.
5. Periodic Breaks: Computer user should alternate between sitting down and standing when a daily task is being performed by taking small breaks away from the seat as well as from the glare of the screen.
6. Chair Adjustment: The height of the chair should be adjusted so that the feet should be resting flat on the floor.
7. Armrest: The chair armrest should be removable; also the distance between the two armrests should be able to be adjusted. The lower arms and the elbow should be relaxing on the armrest to ensure good blood circulation. Raising the armrest too high will raise the shoulder too and might cause pain in the neck and shoulder. The armrest’s height should be adjusted to march individual preferences.

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5.        MONITOR

After adjusting the chair and setting up the work surface, the monitor should be placed in a position that the monitor screen will be at just below eve level with the user is sitting in an upright position. This set up will prevent eyestrain, pain in the neck and shoulder tiredness while using your computer workstation:

1. The monitor’s screen should be always clean and the screen contrast and brightness should be readjusted to suit personal needs.
2. The monitor should be seating directly in front of the person using it. This will prevent the user from twisting the neck repetitively to get a better view.
3. The monitor’s position should be approximately 16-29 inches away from the user to provide comfortable viewing distance.
4. In order to avoid glare, the computer monitor should be place in a right angle position from the window and also make sure that window blinds or curtains are close to shield the sun from reflecting to the monitor.
5. The monitor tilt should be also adjusted to ensure that there is no reflection from the ceiling light.
6. In orders to avoid frequent eye movement between the computer screen and the work being typed, a document holder could be used and placed at the same height as the computer monitor.
7. Computer screen users are recommended to get regular eye test from an optician and inform the optician that they are computer user. .
8. If there’s a need for a large screen arises for example for larger screen requirement for image editing purposes, invest in one and make sure you seat further away from the larger monitor.

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Figure 3 MONITOR POSITION

JI999

Courtesy of the Workers’ Compensation Board of British Columbia.

Prescription glasses wearers have to pay particular attention to the placement of their monitor. Wearers of spectacles often unknowingly tilt their heads backwards so they can read the screen through the lower portion of their glasses. This can sometimes lead to neck, shoulder, and back discomfort. Potential solutions include either lowering the computer monitor or purchasing glasses designed specifically for working at the computer.

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6.        KEYBOARD

In order to avoid problems connected with computer usage, changes should be made to the computer workstation set up. This will in turns stop the user encountering computer ergonomics problems that affects the wrist, elbow and forearm. In order to prevent development of ergonomic problems while using computer, the following changes should be made to the computer workstation.

Figure 4 KEYBOARD

Courtesy of the Workers’ Compensation Board of British Columbia.

Illustrations used with permission.

1. Following the adjustment of chair as mentioned earlier, the next thing is to get comfortable position to use the keyboard. The user arms should be resting comfortably at his side. Then raising the forearm in order to form 90degree angle with the upper arms.
2. The keyboard’s height has to be adjusted so that the shoulder could relax and take away the pressure from the arm. The keyboard tray is essential to allow proper height and distance adjustment.
3. In order to avoid excessive arm stretching trying to reach the keyboard, the keyboard has to be place right in front of the user.
4. The forearms’ position should be about 90-degree angle at the elbow, paralleling to the floor.
5. The keyboard’s height should be the same as the mouse and mouse’s position should be adjacent to the keyboard. This will prevent pressure on the wrist through elevated and extended reach of keyboard and mouse. It’s also a good practice to keep the hand away from the keyboard during idle typing time. Hand could be rest on the lap when the user is not using the keyboard.
6. Palm or wrist rest are supports aid designed for the wrist to rest upon while on break from typing, Palm rest is not supposed to be rest upon when the user is engaged in keyboard operation but to take pressure away from wrist during idle keyboarding period.  
7. Padded wrist rest protects the arms away from edges of the computer table. It also help align the wrist in a straight position during keyboard operation
8. Adjustment should be made to the keyboard for example making sure its in a flat position so that the wrist will be in a straight position during keyboard usage.
9. During keyboard operation, the shoulder arm and fingers should be kept relaxed. Also the keyboard’s keys should be pressed gently and softly and not to be held down for a long duration.

7.        MOUSE AND OTHER INPUT DEVICES

Figure 5 MOUSE AND OTHER INPUT DEVICES

1. The mouse should be the same height as the keyboard and can be at either side of it.
2. Mouse and other input device should placed at arms length of the user and not be put far away from the immediate reach as this will lead to stretching to reach and putting pressure on the wrist resulting in discomfort elbow.
3. In order to avoid putting pressure to the wrist, the user sitting position should be a bit high in a way that the workstation height is a bit below the elbow’s height.
4. Mouse comes in different shapes and sizes. The user should test different types and then choose the one that have the features needed to make their job comfortable.
5. The mouse’s surface should be level to ensure stability

8.        LIGHTING

Computer workstation is recommended to have a lower illuminated area compared to typical room. Brightly lighted area will reflect on the images on the computer screen and can cause loss on the picture quality or glare. Similarly poorly lit computer room could result in symptoms such as burning eyes, blurred eye and double vision. The ceiling light should be avoided, reduced or switched off if possible. The ceiling light can be substituted with a desk lamp if possible.

Figure 6 LIGHTING

Eye strained and Fatigue reduction tips:

1. Curtain or blinds should be shut to avoid glare.
2. Ensure adequate illumination, properly adjusted light to prevent glare on the computer monitor. It is recommended that light source should be 90-degree angle with reduced wattage instead of high.
3. The light should be shielded away from the screen if possible.
4. Monitor glare screen shield could be used to minimise glare from the ceiling light.
5. Computer monitor should be placed at 90-degree angle to windows where possible.
6. Non-reflective paint finish is more suitable for the room where the computer is situated and ceiling lighting should be reduced or avoided.

9.         WORK HABITS

Repetitive static work on the computer can be very exhausting on your upper extremities as well as your eyes. It is important that breaks from working at the computer be taken every 20 to 40 minutes in order for your body to rest and recover.

The Health and Safety Executive (HSE) guidelines suggest that taking short frequent breaks are better than longer less frequent ones. Taking a short breaks does not mean the user have to be totally idle, other activities such as using the phone or anything other than keyboarding and looking at the screen.

It is also important to change positions periodically. Sitting in one position or leaning on your arms for an extended period of time can interfere with circulation.

10.        CONCLUSION

It is quite evident that providing the right equipments such as computer ergonomics products for a safe computing experience is not enough to guarantee a safe use of computer, Human involvement in adjusting the available computer equipments to meet individual needs is paramount. Also making sure the environment around them is conducive for a safe computer use and ultimately maintaining a good working habits while using the computer.

In a nutshell, computer user has to create a suitable and safe environment for computing purpose. They should be disciplined in taking frequent breaks away from the computer and the glare of the screen. Also acknowledging that regular eye check ups and periodical breaks such as few stretches at regular intervals will greatly reduced the chances of sustaining injury related to prolonged computer usage such as eye strain, difficulty in circulation, repetitive strain injury (RSI) and so on

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BIBLIOGRAPHY

Computer Workstation Ergonomics, CDC

 

Accessed 15/08/09

Down, R. (2000) “14 steps to safe and comfortable computer use - the practical ergonomics approach” Ergonomos.

Health and Safety Executive

 

Accessed 10/08/09

Home Accident Surveillance System, 1998, Department of Trade and Industry

J. Almond, Computer Safety, ROSPA  

Accessed 2/08/09

Marc Liron, (2007), Healthy Computing Guide, Microsoft MVP,

Safe computer use, Directgov.

 Accessed 14/08/09