Working Well

A 1984 World Health Organisation Committee report suggested that up to 30 percent of new and remodeled buildings worldwide may be the subject of excessive complaints related to Indoor Air Quality (IAQ).  Often this condition is temporary, but some buildings have long-term problems.  Frequently, problems result when a building is operated or maintained in a manner that is inconsistent with its original design or prescribed operating procedures.  Sometimes indoor air problems are a result of poor building design or occupant activities.

Common causes of poor Indoor Air Quality

Inadequate ventilation
If a building’s heating, ventilation and air conditioning system is not operating correctly, ventilation may be poor and there may be a build up of indoor pollutants.  It is important to strike a balance between optimum ventilation and minimisation of energy consumption, especially given the growing concern with climate change.

Chemical contaminants – Indoor Sources
Most indoor air pollution comes from sources inside the building.  For example, adhesives, carpeting, paints, upholstery, manufactured wood products, furniture polish, copy machines, pesticides, perfumes, air fresheners, deodorants, hairsprays, cleaning products and other aerosols may emit volatile organic compounds (VOCs), including formaldehyde.

Research shows that some VOCs can cause chronic and acute health effects at high concentrations and some are known carcinogens.  Low to moderate levels of multiple VOCs may also produce acute reactions.  A likeness can be drawn between some VOC exposure symptoms and some depression symptoms (eg  fatigue, poor concentration, short term memory loss, brain fog) and a number of new studies are showing chronic VOC exposure may increase the risk of depression.

Chemical contaminants – Outdoor Sources
The outdoor air that enters a building can be a source of indoor air pollution. For example, pollutants from motor vehicle exhausts, plumbing vents and building exhausts (eg bathrooms and kitchens) can enter the building through poorly located air intake vents, windows and other openings. In addition, combustion products can enter a building from a nearby garage.

Biological contaminants
Bacteria, moulds, pollen and viruses are all types of biological contaminants.  These contaminants may breed in stagnant water that has accumulated in ducts, humidifiers and drain pans, or where water has collected on ceiling tiles, carpeting or insulation. Sometimes insect or bird droppings can be a source of biological contaminants.  A recent study has identified a possible link between depression and household mould, a link that can be extended to mould in the workplace.  

Other Causes
Other causes of poor indoor air quality include temperature fluctuations or too low or too high a temperature.  The ideal ranges in a building for temperature are: Summer, 23-26C; Winter, 18-24C. Temperatures below 18C are associated with colds, chills or flu whilst temperatures above 26C are associated with discomfort, headaches and fatigue.  The ideal temperature for an office is 23C.

Dry conditions in offices are common in many parts of Australia due to the use of air conditioning.  Low humidity is associated with dry eyes, nose and throat, increased respiratory illness and static electricity.  In high humidity conditions, workers may experience fatigue, headaches and dizziness.  Biological contaminants including dust mites are likely to increase in number and there is also an increased off-gassing of VOC’s. Humidity can be a concern when levels exceed 70 percent or when they are below 30 percent.  Ideal humidity levels are in the region of 50 percent.

Build up of carbon dioxide (CO2) as a by-product of respiration combined with lack of ventilation can also cause fatigue, loss of energy and poor concentration. By making sure that your workplace is well-ventilated and by eliminating as many pollutants as feasible, you can improve the quality of your indoor air, thereby reducing potential health impacts.

In Australia there are trained professionals who can assess Indoor Air Quality in workplaces. For a workplace assessment, talk to your organisation’s Occupational Health and Safety Officer, a manager or the business owner directly.  An independent audit can be conducted by a building biologist, occupational hygienist or  a heating, ventilation and air conditioning systems specialist.

References: 

US Environmental Protection Agency

Department of the Environment, Water, Heritage and the Arts Australia

Other articles of interest include:

Air fresheners/Aerosols, VOC’s and depression VOC’s and depression  - The Age

Potential Indoor Air Quality Indicator - State of the Environment, Tasmania 

Mould and depression - Brown University