Regulatory Requirements

Transcription

1 Safe Use of Display Screen Equipment The wide application of display screen equipment (DSE) to improve the quality of work and efficiency are commonly recognized in our daily life such as paper work, data input, programming and writing , etc. Use of DSE has potential occupational safety and health hazards to the operator though it seems to be low risk. Problems like developing upper limbs disorder and back pain as well as other symptoms of visual discomfort, muscle fatigue, and work and mental stress are common after prolonged use of DSE. Regulatory Requirements According to the Occupational Safety and Health (Display Screen Equipment) Regulation, the person responsible for a workplace shall perform a risk assessment of a workstation in the workplace and to take steps to reduce any risk identified in the risk assessment to the lowest extent as is reasonably practicable. Employers should ensure that their employees are provided with necessary safety and health training in the use of DSE workstations. Employees should on the hand conform to the system of work and work practice and comply with the risk reduction measures. Equipment

2 Display Screen The screen should give a clear, sharp and steady image. The characters should be of adequate size, with adequate spacing between the characters and the lines. The brightness and contrast of the image should be easily adjustable. The screen should be swiveled and tilted to suit the needs of the user. A viewing distance where the image could be comfortably read, for example, should be about 350 to 600mm; and the first line on screen should be at about or just below eye level. Keyboard The keyboard should be tiltable and detachable from the display screen so that the user adopts a comfortable working posture. The surfaces of the keyboard and keytops should be non-reflective. The letters and symbols on the key tops should be clear and easily recognizable. There should be sufficient space in front of the keyboard to provide support for the hands. The table edge should be preferably rounded. If the user spends long time for typing, a wrist support pad may be considered so as to reduce the stress at the user's wrists. The keyboard should be at appropriate position in such a way that the forearm is at about right angle to arm. Work Surface The work surface should be large enough for the screen, keyboard, document and peripheral equipment. The best practice is that the heights of the work surfaces for the screen and keyboard should be adjustable to suit the needs of the user. There should be adequate legroom below the work surface. Chair The seat height should be adjustable in the range of 400 to 500mm. The backrest should be easily adjustable in both height and tilt to provide

3 adequate support to the lower back. Armrests, if provided, should not interfere with keyboard operation. The chair should have a stable base (preferable with a five-pronged base) and smooth castors should be provided at its base to allow easy movement if mobility is required. The seat pan should be of appropriate hardness and the front edge should be scrolled. Footrest A stable footrest should be made available to the user if the chair is too high for the feet to rest firmly on the floor. Document Holder

4 If there is a need to input information from reading the respective document. Document holder should be provided and is properly positioned to avoid awkward neck posture and movement. Environmental Illumination General lighting and / or supporting lighting should be suitably provided with luminance level of the work area around lux. Reflections and Glare The screen should not be positioned directly under the source of illumination or near the window so as to prevent glare and reflections. The screen should be placed at the right angle to the source of illumination and windows while sunlight through windows can screened by blinds. Noise Noise generated from printer or copying machine could disturb the user and therefore, they should be controlled, for example, use a barrier to surround the noisy equipment away from the user. For general computer work, a noise level below 60dB(A) is optimal.

5 Temperature and Humidity Temperature and relative humidity at workplace should be controlled at appropriate and comfortable level. Room temperature should be kept at C (summer) and C (winter) and the relative humidity should be 40-70%. Ventilation Workplace should have good ventilation in order to ensure fresh air supply to the workplace. Administration Control Administration control such as providing appropriate training about the correct postures and re-scheduling the tasks for reducing the working time with DSE can improve the safe use of DSE. Employers should provide safety and health training on working with DSE. The contents of training can be focused but not limited to the following items: Viewing the Screen In additional to the viewing distance at about 350 to 600mm, the angle of

6 viewing is important. The screen should swivel and tilt correctly to make viewing comfortable in order to avoid awkward neck posture. Using keyboard The keyboard should tilt to a suitable inclination for proper keyboard operation. Excessive inclination can cause extreme wrist bending. Wrist position should keep straight or at most slight inclined. Position of mouse Mouse should be positioned at an easily reachable distance to the operator so as to avoid excessive extension of forearm and keep the wrist in neutral posture. Sitting posture Good sitting posture should have the back straight and should avoid twisting the trunk. The backrest should be adjusted to provide adequate support to the lower back. Avoid maintaining a fixed posture for a long time by changing posture to facilitate blood circulation. Short breaks & Exercise Arrange short breaks to relieve muscle strain arose from prolonged keyboard

7 operation. Viewing distant object after prolonged viewing of DSE to alleviate eyestrain and exercises for visual comfort are recommended. Prolonged DSE work can induce muscle fatigue in upper limbs and low back. Stretching exercises for DSE operators are recommended during the rest breaks since the exercises are effective in reducing mental stress as well as muscle strain. Apart from DSE work, job allocation should also be arranged in such a manner to incorporate different varieties. For example, mix of DSE work with photocopying and other paper work. This arrangement not only helps to minimize static or repetitive movement, but also takes chances for different muscle groups to rest. Conclusions Our working practices are moving towards paperless due to the widespread use of computer in our daily life. Frequently use of display screen equipment can arise various safety and health problems to the users though it can enhance work efficiency. The Occupational Safety and Health (Display Screen Equipment) Regulation has specified the ways to guide the prolonged use of computers' works. Employers shall perform a risk assessment of a workstation in the workplace and take appropriate safety measures to ensure the safety and health of the users as according to the findings of the risk assessment. Besides, employees shall cooperate with employer to follow the safety measures that have been arranged by the employer in order to reduce the identified risks. In addition to these safety measures, employees shall operate the display screen equipment with correct postures as well.