Odour, or smell, is experienced when one or more chemical compounds in a gaseous form stimulate the sense of smell. They can range from a pleasant fragrance or aroma to an unpleasant stink or stench. Odours can also cause significant impacts on people’s lives and adversely affect their amenity.
Repeated exposure to nuisance levels of odour can lead to a high level of annoyance. While some people may become acclimatized to odours, others may be negatively affected. An individual’s response to odour may be influenced by a variety of factors including:
- The state of their health
- Previous experience with the odour
- Their relationships to the party generating the odour
Most odours are generated by bacteria, mould and chemicals, that are microscopic, and the offensiveness can be subjective as it relates closely to an odour’s ‘hedonic tone’, which is the degree to which an odour is perceived as pleasant or unpleasant. Odour offensiveness is also related to its character – what the odour smells like.
Character can distinguish between different odours, for example ammonia gas has a pungent and irritating smell. The character of an odour may also change with dilution. For these reasons, odour offensiveness is difficult to quantify.
The age of a property may increase odour problems because newer buildings tend to have air systems that include filtering, cleaning and processing units whereas older buildings may not. In any property there are some simple and affordable ways to effectively control indoor air pollution and odours; steps you can implement immediately.
Control the source of odours in a few simple steps…
Reduce the source of the smell. Put the source away somewhere safe; for instance, store cleaning chemicals in a locked cupboard and keep the bin area away from the property.
Clean all hard and soft surfaces routinely and thoroughly to prevent mould and bacteria growth.
Steam. Effectively remove the source of many bad smells with steam. This method is environmentally friendly; using only pure water to penetrate all surfaces, destroying odour-causing residues and leaving surfaces deep-cleaned, sanitised and refreshed. Safe, if used correctly, this leaves rooms with a natural, clean smell.
Dry. Keep on top of all maintenance issues because neglected leaks/drips rapidly cause mould and smells.
Separate wet areas from dry. Keep bathroom and laundry doors closed to reduce humidity.
Ventilate. Install an exhaust fan close to the source of pollutants or moisture, such as the cooking stove, dishwasher, tumble drier and washing machine. Open windows and run ceiling and bathroom fans (make sure they are working well) when needed.
Beware of garbage chutes and disposals: by their design, they have an updraft hat can transport airborne bacteria and smells back into living spaces. Review and repair your chute as required.
What else is available?
Foul odours need to be eliminated quickly and efficiently. To supplement the source control and ventilation actions, one might consider other cleaning methods, such as:
Odour neutralisers: Used to minimise unpleasant odours by reacting with the offensive molecules. This tends to be a short-term fix until the cause of the odour is eliminated.
Air purifier: A device to remove contaminants from the air, marketed as beneficial to allergy sufferers and asthmatics, aiming to reduce or eliminate second-hand tobacco smoke.
Filters: purification traps and high-efficiency particulate air (HEPA) is a technology that has been around for years; air is forced through a very fine fibre-like material that has been folded back and forth and 99.97 percent of particles are reportedly captured. HEPA purifiers require that the air going into a room does not bypass the HEPA filter.
Activated carbon technology: a form of carbon that is very porous with high absorbance abilities, effective at capturing pollutants, such as chemical emissions, gasses, tobacco smoke and other odours.
Negative ion air purifiers: using negative ions (simple oxygen atoms that have gained an electron) to magnetically attract airborne particles such as pollen and dust, until the newly-formed particle is too heavy to remain in the air. Fan-less ionisers use little power and are quiet but are less efficient then fan-based ionisers that can clean and distribute air faster.
UV technology: used with a particle filter, can sanitise and purify the surrounding air and surfaces. Microorganisms, such as bacteria and viruses, are destroyed by passing through the UV light, the effectiveness of this type of air purifier is dependent on the wattage of the light and the time of exposure. Beware, UV lamps should be monitored and replaced as per recommendations.
Ozone odour elimination: very popular in the hospitality industry because one machine can be utilised for multiple areas and can quickly and effectively eliminate odours. An ozone generator is designed to produce gas ozone and is used effectively in water purification; however, in air, ozone must reach high levels to remove air pollutants.
Be warned, high levels of ozone can exacerbate respiratory illnesses and so people should not be allowed in the area at the same time as the ozone treatment and for a time after. If you are considering using ozone air cleaning technology, always ensure that it is sued correctly, fit-for-purpose and engineered for the task. Remember, other technologies can also emit small amounts of ozone as a by-product.
Plasma technology: some air purification devices on the market utilise this technology for the removal of airborne and surface contaminants using a variety of sources of energy to produce ‘plasma’.
Remember, for optimum effect, whatever odour control system you use should be sized to the room, properly installed, used per instructions and well maintained. Always purchase from an industry supplier and consider the costs of maintenance and replacement filters.
If your building is experiencing an unacceptable or unmanageable odour problem, you are advised to contact the state government’s Environment Protection Authority (EPA) or your local council.
