Odour management
Health and wellbeing impacts
Repeated exposure to nuisance levels of odour can lead to a high level of annoyance and can also be detrimental to peoples’ health and wellbeing. While some people may become acclimatised to odours, others may become sensitised to them.
Source: EPA Victoria
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 (for example ifa person’s livelihood is dependent on the facility causing the odour they will be more likely to accept an odour than a person who does not benefit from it in any way).
Examples of the impacts of offensive odours include:
- interference with backyard activities such as barbecues, having visitors or gardening
- infiltration into homes or prevention of windows being opened
- physiological and psychological health impacts triggered such as stress, headaches, nausea, shortness of breath or aggravating asthma symptoms
- interference with a person’s capacity to work.
Odour management
The EPA requires licensed facilities to take all reasonable and practicable measures to prevent or minimise odour. Other odour issues within the community are regulated by local councils under the Local Nuisance and Litter Control Act 2016.
The overall objectives in the management of potentially odorous activities are to:
- minimise odour emissions and their impacts
- ensure industry or facilities do not expose neighbouring land users to an unacceptable level of odorous emissions
- ensure that industry manages odour emissions within the accepted criteria; and
- apply ongoing risk evaluation and management principles that evolve as the scientific understanding of odours and their potential health impacts evolves over time.
Measuring odour
Odour, or smell, is experienced when one or more chemical compounds in a gaseous form stimulate the sense of smell. An odour can be made up of many chemical compounds and while chemical compound levels can be measured, the impact on humans can only be measured by human senses. The way people experience odour is still poorly understood and a person’s sensitivity to odour can vary greatly. A person with an overly sensitive sense of smell will experience a greater reaction to odours while another person may be ‘anosmic’ and possibly cannot even experience most odours. The only way to measure odour is by using people that have been tested to have an average odour sensitivity.
Odour is a highly subjective experience. An odour that someone considers offensive, another might truly enjoy. Odours can range from a pleasant fragrance or aroma to an unpleasant stink or stench – depending on the person smelling them. Odours can also cause significant impacts on people’s lives and adversely affect their amenity.
Unacceptable odour
Complaints will occur when individuals consider the odour to be unacceptable, and become sufficiently annoyed to take action. As well as an individual’s sensitivity, 5 factors influencing odour complaints are:
- frequency of the occurrence (how often do you experience the odour?)
- intensity (how strong is the smell and how is it affecting your amenity?)
- duration of exposure (how long is the odour present?)
- offensiveness (is the odour objectionable or pleasant?)
- location of the odour source.
The intensity of an odour will vary with a person’s sensitivity and the offensiveness is also very subjective. This 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.
Lastly, the frequency and duration that a person experiences an odour may also make it more or less offensive. If you work in an odourous industry you can become acclimatised. Conversely even a pleasant odour, like a bakery, may become offensive if you are exposed to it repeatedly over a long time. 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
If you are experiencing unacceptable odour from an industrial or commercial facility, find out if the site is licensed by the EPA. If this is the case, you will need to complete an odour diary. This will help us to identify where the odour may be coming from, why it is occurring, and allow us to determine what further action is required to collate evidence.
Please email the diary once completed keeping in mind that your diary could become evidence to help us investigate and prosecute.
If the odour source is not from a licensed facility, you can contact your local council. You can use the odour diary to provide the same information so that they can determine the necessary action. For instance the frequency or duration of an odour nuisance may point to a particular process that has changed within the industry or business and then the EPA or council can work with them to remediate the odour more effectively by targeting that process.
