Calculations: Workstations With Computer

Workstations equipped with a computer must accommodate at least a visual display unit (VDU) and an alphanumeric keyboard. There is no standard for such workstations because the requirements vary widely depending on individual work processes (e.g. from a simple networked terminal for enquiries to stand-alone systems for data entry and manipulation, which in addition to the VDU and keyboard may also have disk drives, scanners, printers and other peripherals).

These workstations should be designed according to national safety requirements and generally accepted technical standards for good practice based on an understanding of ergonomics.

Workstation design. Items that are used frequently should be placed within the preferred field of vision and reach area – (1) – (3).

The best working position is when the person is seated with the upper arm perpendicular to the floor and the forearm at a 90° angle. The thighs should be parallel to the floor with the lower leg at a 90° angle - (4). The table and chair must be adjustable to allow proper positioning for users of different heights. Two ergonomic systems are equally acceptable.

Sufficient leg clearance should be provided - (6). In work areas, all items of equipment close to the user (on the desk top, etc.) should have a 20-25% reflection factor. Illumination should be between 300 and 500Lx, and glare from lights must be limited (e.g. by providing specular louvred ceilings above VDU stations). Arrange lighting strips parallel to the window. Matt surfaces in the room should have the recommended reflection factors (ceiling approx. 70%, walls approx. 50%, movable partitions approx. 20-50%).

The worker's line of sight to the monitor should be parallel to the windows and to any lighting tubes; the monitor should be between these if possible. It is necessary to install blinds to control daylight at visual display workstations.

Follow local recommendations for environmental control and noise protection. The increased use of heatgenerating electronic equipment in offices tends to result in the need for additional cooling to maintain a comfortable temperature.

The impact of information technology. Employment usually required attendance at a place of work because the materials and tools were there, and the work needed to be supervised. However, advances in information technology mean that the 'material' for most office work (information) can be transmitted electronically. The tools of office work are increasingly a telephone and a workstation, both of which can be installed at home. Innovations in communication technology are gradually having a major impact on how the work environment is defined.

It is also freeing many workers from geographical constraints. The free-address workstation is becoming a technical reality, with portable voice and data links to anywhere in the world. However, the free-address workstation has implications for both people and organisations, such as the need for increased social interaction and new management techniques which are able to cope with a widespread workforce.