University of New South Wales - Human Resources - Ergonomics

Indoor Climate

Ventilation

The basic requirement for adequate lighting is that the work must be easy to see and the light comfortable to the eyes. Illumination is measured in units of LUX - lumens per square metre.

Suitable light levels based on Australian Standard AS 1680 - 1990 Interior Lighting are: -

General background 200 Lux
Routine office work (typing, filing) 400 Lux
Work with poor contrast (proof reading) 600 Lux

Appropriate lighting is important to minimise unnecessary eyestrain and to ensure that an appropriate posture is maintained. For example when individuals find it difficult to see what they are working with they tend to lean closer, which results in an awkward posture. Excessive light levels (greater than 1000 lux) can cause headaches.

Helpful hints

The Risk Management Unit can perform light measurement assessments. To arrange an assessment contact OHS Administration on 9385 1565 or 9385 2911

Glare and reflections

Glare and reflection can result in eye discomfort and strain. Glare and reflections can occur from overhead lights, poor lighting positioning, and type of lighting or external light sources (eg. windows). To check for reflections place book or object between light source and desk or monitor to determine whether reflection is reduced (Australian Standard AS 1680.2.2 1994 ).

Helpful hints to eliminate or reduce glare and reflections

Utilise blinds to control light from windows.
Re-orientate workstation to minimise the amount of light falling on work area.
Overhead lighting should be fitted with glare reducing diffusers. The light should fall from the side rather than the front to avoid reflections on the work surface.
Windows should be to the side of the user if possible, not directly behind or in front of the screen.
Tilt the screen so that reflections are directed below eye level.
Cover screens with an anti-glare screen. It is important to be aware that the use of anti-glare screens can reduce the brightness of the monitor, so they should only be used when the above strategies are not effective.

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Noise Standards

Noise is often described as any disturbing sound. Sources of noise may include:

Office Equipment (eg. telephones, printers, photocopiers)
People (i.e. conversations)
Background noise (eg. lifts, air conditioning, traffic)

Most noise levels in the office areas are below levels known to result in risk to hearing, however they can be distracting to concentration and / or affect communication.

Hints for controlling office noise

Isolate noisy equipment such as printers or photocopiers by positioning them in separate rooms, or by fitting screens
Use sound absorbing materials for internal walls and partitions, window glazing if external traffic
Select equipment with lowest noise specifications
Lower the ring volume setting on a telephones
Establish local area guidelines ie. areas to have conversations
The Risk Management Unit can perform noise measurement assessments. To arrange an assessment contact OHS Administration on 9385 1565 or 9385 2911

Refer to AS/NZS 2107:2000 for further information on managing noise in the work place.

Taken from Officewise Office Safety - Designing a Healthy and Safe Working Environment, Comcare Australia (March 2004).

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Indoor Climate

Maintaining a comfortable climate indoors is essential for both health and comfort of the worker, as well as ensuring optimum work performance. The factors which most affect comfort are:

Temperature
Humidity
Air movement
Odours

The sensation of comfort varies from individual to individual and the aim is to provide a comfortable environment for the maximum number of people in a particular environment.

Thermal comfort can be affected by nearby windows and the placement of air conditioning outlets and/or heating ducts and fans. Cool draughts around the neck or the feet are particularly unpleasant and can cause muscle contraction. The heat emissions from computer equipment and printers should be taken into account. WorkCover recommended temperatures for sedentary work in summer is between 21°and 24°Celsius. The preferred winter temperature is usually about 2 degrees lower than in summer.

The relative humidity of the air affects the mucous membranes of the eyes, nose, mouth and throat. The optimum range for relative humidity is 40% - 50%. Relative humidity below 30% can cause dryness of the eyes, nose and throat and may also result in a build up of static charges. High relative humidity above 80% can cause fatigue and may give rise to complaints of stuffiness.

Odours may result from human intervention, for example work of contractors resulting in paint fumes being circulated through air conditioners. Odour may also result from the natural environment, for example urine of feral cats in garden or fertiliser smell.

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Ventilation

Ventilation refers to the movement of air and rate of fresh air input. Air movement of less than 0.1 metres per second can lead to stuffy rooms whereas air movement of more than 0.2 metres per second causes draughts to be felt.

The Australian Standard AS 1668.2 - 1991 Mechanical ventilation for acceptable indoor-air quality sets out the absolute minimum requirements for fresh air. For each person, a minimum rate of 10 litres per second per person for general office space or 10 litres per second for every 10 square metres of floor space is recommended.

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