Designing a healthy and safe working environment

Humans can see quite well in a wide range of lighting levels because our eyes adapt to different lighting conditions. For example, when we move from a bright room into a relatively dark area. Some tasks have recommended levels of lighting to reduce the:

• demands on eyes
• need to adapt when changing tasks or viewing fields.

How light is measured

A light meter, also known as a lux meter, can measure:

• The amount of light in an area.
• The amount of light falling onto a surface. This is known as the illuminance of that surface and is measured in lux.

Table 1 shows the recommended illuminance for different types of work as set out in AS/NZS 1680.1:2006: Interior and workplace lighting, Part 1: General principles and recommendations. The levels for the different types of work areas are approximate.

Table 1: Australian/New Zealand standard guidelines for lighting levels

Information adapted from AS/NZS 1680.1:2006

Quality of light

Quality of light refers to the level of lighting and other factors that affect how well people can perform a task. Factors affecting quality of light include:

• The number of lights in use. Having the correct number of lights will provide evenness of lighting over the area.

• The type of lights. For example:

  • LED
  • fluorescent tubes
  • compact fluorescent
  • tungsten
  • halogen.

  LEDs use about 75% less energy than halogen light bulbs and last 5 to 10 times longer.

• The type of light fittings used. The design of light fittings can influence the direction of lighting.
• The position of the lights. Lights should be positioned to illuminate workstations.
• How colours appear under the lights.
• Maintenance of the lighting system.
• Sunlight. Installing skylights, transparent roof panels or light tubes can maximise the use of sunlight for internal lighting.

When planning lighting for office environments, employers should consider:

• all the above factors
• consulting a lighting designer when designing lighting in a new office area.

Natural light

When identifying, assessing or controlling lighting issues, remember that the time of day and year will affect the quantity and quality of natural light in a work area. This is particularly important when designing lighting systems.

Natural light entering a work area may cause lighting issues. Enabling employees to control and adjust natural light can help. For example, by providing venetian or vertical blinds.

Colour

Choice of colours can determine the mood of an environment and the level of reflection from a surface:

• Ceilings are usually white or off-white and should reflect around 80% of the light.
• Walls should reflect between 50% and 75% of light and be painted in subdued cool colours with a gloss or semi-gloss finish.
• Floors should be less than 20% reflective and be darker and not glossy if painted.
• The use of colourful posters or non-reflective paintings can relieve monotony and provide visual relief.

Flickering lights

Some lights can be a source of annoyance, particularly older fluorescent tubes that may flicker when malfunctioning. Flickering or flashing lights can trigger seizures in people with photosensitive epilepsy.

Lighting needs to improve the visual environment and be free from flicker and stroboscopic effect as well as glare. Regular maintenance will help control light flicker.

Stroboscopic effects can also cause the illusion that rotating or moving machinery:

• is moving slowly
• is moving backwards
• appears stationary.

This can be a cause of accidents. Lamps should be wired to eliminate the stroboscopic effect.

Glare in a work area

Glare occurs when one part of an area is much brighter than the background or vice versa. For example, if a bright window is behind a computer screen, the contrast between dark and light can be so great that the eyes must adapt constantly to the change. This can cause eye fatigue and headaches, as well as make it harder to view the screen.

There are several ways to reduce glare, including:

• Controlling natural light from windows. For example, blinds enable employees to adjust the light in their work areas.
• Reducing the contrast between the foreground and background. For example, using a slightly darker partition with a matte surface reduces the contrast between a computer screen and the surrounding area.
• Repositioning the workstation to reduce the light falling on the work surface.
• Reducing the general lighting to suit the task being performed.

Reflections from a work surface

Light reflected from a surface can make it difficult to see what is on the surface. For example, it can be difficult to read a screen when light from artificial lighting or windows reflects onto the screen.

To identify reflections, observe a work surface or screen and ask the operator if reflections make it difficult to see their work. Don’t forget, light from windows changes during the day and with the seasons.

To check for reflections, hold a sheet of paper above a computer screen or place a mirror over the work surface to reveal the source of reflections visible from the usual working position. Check whether the mirror shows overhead lighting or other sources of light as a problem for that work surface.

Controls for reflections include positioning computer screens side-on to the main light source. A light screen background also reduces difficulties caused by reflections.

If the reflection problem remains, consider moving the workstation to another position. Removing reflections is important when the screen is used for prolonged periods. Use the controls in this guidance rather than screen filters. These can reduce the quality of the screen display and require regular cleaning.

Annoying reflections can also occur in workplaces where there are highly polished floors or glass-covered wall paintings. Employers should address these issues when planning and setting up an office. Even glossy paper documents can reflect light and become unreadable.

Figure 2: Preferred placement of the screen to reduce reflections

Shadows across a work surface

Shadows can:

• reduce the visibility of work
• add to glare problems
• lead to poor posture.

Holding a piece of paper above the viewing surface can show if shadows fall over that work surface. A person’s posture can also indicate if shadows affect their work.

The main ways to reduce shadows are:

• increasing the number and spread of overhead lights
• moving work
• redirecting lighting
• removing or relocating barriers that prevent light falling on the work surface.

An adjustable task lamp can provide lighting where:

• shadows are a problem
• light from a particular direction is required
• an increase in general lighting is not practicable.

However, a task lamp can create pools of light that force eyes to adapt rapidly when looking at the whole work surface. For this reason, removing the barriers to light falling on the work surface is the preferred control measure to remove shadows.

When employees find it difficult to see what they are working on, they often:

• lean closer to the object
• bring it closer to their eyes.

In both cases, this may lead to an awkward posture. If an employee adopts poor posture to read or see their work, then shadows, glare or reflection may be a problem.

Employees who report discomfort at work should be observed performing their usual duties. A well-supported, neutral posture is less likely to result in discomfort.

If an employee is not well supported by their chair, leans towards their work or adopts a hunched-over posture, there may be a problem caused by:

• poor lighting
• poor screen design or position
• uncorrected visual problems.

If lighting is contributing to poor posture, the location and all aspects of lighting relative to the task need to be considered. For example:

• Is a shadow being cast over the work surface?
• Is there enough light for the task being performed?
• Are reflections or glare causing the employee to adopt an unsatisfactory posture?

Where visual problems are thought to exist, advice should be sought from a medical specialist or optometrist.

Eye muscles can become tired when constantly focused on close work. To identify if visual fatigue is an issue in the workplace, ask employees if they get tired eyes or other eyestrain symptoms.

To control visual fatigue, employees can change their focus. For example, by looking out a window or to a picture along a hallway. This will exercise other muscles of the eyes while resting the tired muscles. A helpful approach is the 20-20-20 rule:

• for every 20 minutes of computer work
• look 20 metres away
• for 20 seconds.

For more information, see ‘Eyestrain and headaches’ in Office layout and design.

Workplace noise can come from:

• Inside the building. For example, equipment, people and background noise.
• Outside the building. For example, road traffic and general industrial noise.

Background noise generally goes unnoticed unless equipment breaks down. Some background noise can help to make a quiet environment less uncomfortable.

Figure 3: Common noise levels in decibels

Noise in office areas is unlikely to be at a level that can pose a risk to hearing. Instead, it is likely to be an annoyance. It may:

• interfere with communication
• distract employees
• affect how well employees do tasks like reading and writing.

This type of noise can also:

• contribute to work-related stress
• be costly for an organisation
• be a safety risk if it stops someone from understanding an instruction or warning signal.

Employers can use the following noise control measures:

• Design the space to separate noise-making activities or equipment from tasks requiring concentration.
• Put noisy equipment such as printers or photocopiers in separate rooms.
• Use sound-absorbent materials like:
  • suitable floor coverings
  • wall panels
  • ceiling panels
  • dividing screens.
• Use acoustic-grade dividing screens to reduce conversation noise. Partitions should:
  • be 1200 mm high between employees and 1600 mm high between workstations
  • be used with other sound-absorbing surfaces like floors, walls and ceilings
  • not affect ventilation or make employees feel isolated.
• Choose equipment with the lowest noise specifications practicable.
• Use noise barriers like double-glazed windows, solid walls and fences. This will reduce external noise.
• Lower the volume setting on disruptive telephones.
• Arrange workstations so that phones are not placed near to the ear of nearby colleagues.
• Locate break or meeting areas away from workstations.
• Provide soundproof booths for phone work or meetings.
• Provide noise-cancelling headphones.
• Encourage employees to have conversations in meeting areas away from work areas.

If you can’t control unwanted noise, consider using masking sound. This is electronic background noise to mask or cover intrusive noises. Masking is generally an unsatisfactory way to deal with unwanted noise. It may be necessary to consult an expert on this issue.

To find out more about how to identify, assess and control excessive noise levels, see:

• the OHS Regulations
• WorkSafe’s Compliance code: Noise
• AS/NZS 2107:2016: Acoustics – Recommended design sound levels and reverberation times for building interiors.

Some privacy during conversations is necessary, particularly in open-plan offices. Breakout or quiet rooms can provide spaces for private conversations.

Privacy requirements should be considered at the design stage of the office layout when deciding the:

• distance between employees
• orientation of workstations.

Partitions can provide privacy between workstations. Using partitions involves considering the design of the whole office environment. This includes the size, construction and continuity of partitioning and all other surfaces in the office.

Expert advice should be sought when designing partitioning to provide speech privacy. For further information, see AS 2822-1985 (R2016): Acoustics – Methods of assessing and predicting speech privacy and speech intelligibility.

To identify disturbing noise sources in an office, it is best to ask the employees working in the area a series of questions. For example:

• What noise is most disturbing, if any?
• When does it occur?
• What effect does it have?
• How do you deal with disturbing noise?

A general walk-through survey interviewing employees can identify noise in the office.

Where noise issues are a problem in an office environment, employers should do an assessment and develop noise control measures. It may be necessary to consult a qualified person for a specialist assessment or advice.

To identify thermal comfort issues in office environments, employers should ask employees working in the area a series of questions such as:

• Do you find the atmosphere hot, cold, stuffy or draughty?
• When do you notice these conditions?
• What effect do these conditions have on your work? 
• Do the conditions affect your ability to complete your work?
• How do these conditions affect you?
• Where do you notice these conditions?

In cases where employees have identified problems with thermal comfort, an appropriately qualified person should assess thermal comfort issues. Employers must develop control measures in consultation with employees, so far as is reasonably practicable, and any HSRs.

The working environment and weather will affect thermal comfort, but general suggestions for improving temperatures and air quality include:

• air conditioning regulated for temperature and humidity
• fans
• electric heating
• open windows
• layout and location of workstations – avoid locating workstations directly in front of or below air conditioning outlets
• installing deflectors on air vents to direct airflow away from people and help prevent employees being annoyed by draughts
• controlling direct sunlight and radiant heat with blinds, louvres and window treatments
• ensuring proper building insulation
• minimising draughts and thermal differences between employees’ heads and feet
• ensuring adequate air flow
• work and rest regimes.

All heating and cooling facilities need to be serviced regularly and maintained in proper working order.

Where air quality is identified as a problem, employers should get an appropriately qualified person to assess the air quality and act as recommended.

Employers should ensure workplaces are adequately ventilated with fresh, clean air that is:

• drawn from outside
• uncontaminated by discharge from flues or other outlets
• circulated through the workplace.

You should also ensure the air conditioning system:

• provides a comfortable environment for air temperature, humidity and air movement
• prevents the excessive accumulation of odours
• reduces the levels of respiratory by-products, especially carbon dioxide, and other indoor contaminants that may come from work activities
• supplies an amount of fresh air to the workplace, exhausts some of the stale air, and filters and recirculates some of the indoor air
• is regularly serviced and maintained in accordance with the manufacturer’s instructions.

See ‘Airborne diseases’ in General health and safety issues in the office for more information on heating, ventilation and air conditioning systems.

General health and safety issues in the office

The building needs to be adequately cleaned, with carpets vacuumed and dust removed, on a regular basis.

Employers should also ensure that employees:

• Avoid adding odours to the air, such as fragrance oils and incense. These can travel through the air conditioning system to other parts of the building.
• Are aware of what they are cooking in the kitchen. If installed, they should use exhaust fans to remove cooking odours.
• Report leaks or areas of damp.

Bushfire smoke and smoke from planned burns can be hazardous. It can be more harmful for:

• people with chronic health conditions
• older people
• pregnant women.

During smoky conditions, employers should check whether the cause of smoke is a bushfire or planned burn. You should:

• check for planned burns with Forest Fire Management Victoria
• call the VicEmergency Hotline on 1800 226 226
• follow the relevant advice or message.

To reduce the effects of smoke:

• avoid physical activity
• stay indoors
• close windows and doors
• switch the air conditioner to recycle or recirculate
• if necessary, leave the area while it is affected by smoke
• seek medical advice for anybody suffering symptoms that may come from smoke.

When the air quality is poor because of bushfires, it can affect the health of employees working indoors. This is due to Heating Ventilation and Air Conditioning (HVAC) systems drawing in outside air.

Information on how to control the risk of exposure to bushfire smoke.

Photocopiers produce small amounts of the gas ozone. If present in sufficient concentration, this odorous gas is irritating to the eyes, lungs, throat and nasal passages. Under normal circumstances, the concentration of ozone from a photocopier is not sufficient to cause symptoms such as itchy eyes or illness.

For more information, see the most recent version of Safe Work Australia’s Workplace exposure standards for airborne contaminants.

The concentrations of ozone within the breathing zone of the operator depend on the:

• amount of ozone discharged by the copier
• rate of decay of ozone
• volume of air in the room
• temperature
• ventilation in the room.

Odour problems with modern copiers and fax machines usually indicate inadequate ventilation.