Odour management
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.
Health impact
Repeated exposure to nuisance levels of odour can lead to a high level of annoyance. While some people may become acclimatised to odours, others may become sensitised to them. 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 relationship to the party generating the odour (if a person’s livelihood is dependent on the facility the perception may be less than a person who does not benefit from it in any way).
The EPA’s role in odour management
The EPA is responsible for ensuring those facilities it licenses are taking all reasonable and practicable measures to prevent nuisance odour.
The overall objectives in the management of potentially odorous activities are to:
- minimise odour emissions and their impacts
- ensure industry or facility does not expose neighbouring land users to an unacceptable level of odorous emission
- ensure that industry manages odour emissions within the accepted criteria
- apply ongoing risk evaluation and management principles that evolve as scientific understanding of odours and their potential health effects increases over time.
Odour complaints occur when individuals consider the odour to be unacceptable and are sufficiently annoyed by it to take action. As well as an individual’s sensitivity, 5 factors that influence odour complaints are:
- frequency of occurrence
- intensity
- duration of exposure
- offensiveness
- location of the odour source.
The offensiveness of an odour is very subjective and 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. However, the other 4 factors are quantifiable and can be built into a regulatory guideline.
Reporting odour nuisance
