Dynamic Olfactometry Testing
We perform dynamic olfactometry using validated equipment, controlled dilution sequences and strict QA checks. Results are suitable for dispersion modelling, impact assessment and compliance reporting.
In-house odour analysis with a six-assessor panel, a 15 to 2,500,000 dilution range and a 29 odour unit reportable limit, for impact assessment, approvals and complaint response.
Air Environment operates an in-house odour testing laboratory to support high-stakes odour investigations, approvals and complaint response. Our laboratory is NATA accredited operationally to ISO/IEC17025 and the dynamic olfactometry testing standard AS EN13725. By controlling the full sampling and testing workflow, we deliver reliable datasets, consistent methods and clearer interpretation for decision-makers.
We perform dynamic olfactometry using validated equipment, controlled dilution sequences and strict QA checks. Results are suitable for dispersion modelling, impact assessment and compliance reporting.
We collect representative odour samples from stacks, area sources and fugitive emission points using documented sampling procedures. Chain of custody and sample handling are digitally managed to protect data integrity.
We translate laboratory results into practical assessment inputs for odour dispersion modelling and impact evaluations. This helps define risk, compliance margins and priority mitigation areas.
We manage an assessor panel program with screening, performance monitoring and ongoing calibration. This supports consistent, defensible olfactometry and field odour surveillance program outcomes.
Not all odours are created equal. The concentration of an odour is only one important piece of the puzzle. How the odour’s intensity and hedonic tone is perceived at different concentrations is critical to understanding how people react to smells. Where required, we assess odour intensity and hedonic tone to better describe and understand these perceptions. This supports risk- based interpretation and communication of likely impacts.
We deliver clear reports that document methods, assumptions and results in a review ready format. Outputs are suitable for councils, regulators, licence submissions and independent technical review.
The integration of in-house laboratory capabilities ensures complete control over data quality, testing timelines, and assessment outcomes - delivering the technical rigour required for successful project approvals and ongoing compliance management.
Advanced olfactometry equipment and streamlined laboratory procedures enable significantly faster odour panel sessions with higher sample throughput. This efficiency translates directly to reduced costs and timelines from field sampling to final results, so projects can respond quickly and keep approvals moving.
Higher sample volumes per testing session generate statistically robust datasets that improve both accuracy and reliability of odour assessments. Standardised methods, controlled laboratory environments, and minimised sample handling reduce variability while ensuring consistent, repeatable results that withstand rigorous technical scrutiny.
Robust emission datasets with extensive data points strengthen the foundation for odour dispersion modelling and comprehensive risk assessments. This enhanced data quality enables more defensible impact assessments that support confident decision-making throughout regulatory review processes and potential legal challenges.
AS EN 13725 requires samples to be analysed within 30 hours of collection. When sampling and analysis sit with the same team, the panel session is booked around the field program rather than the other way around. No freight risk, no waiting on a third-party laboratory's schedule, and no samples written off because they arrived an hour late.
Odour is not measured with an instrument that reads a number off a screen. It is measured with people, under controlled conditions, and the result is a dilution factor. Understanding that is the difference between reading a report and being able to defend one.
Swipe the chart sideways to see the full dilution range.
We clarify what must be proven and what the project needs to achieve.
Monitoring, sampling and modelling designed to be credible and efficient.
We interpret results, test assumptions and quantify uncertainty where needed.
Regulator-ready reporting, stakeholder clarity, and support through next steps.
Andrew’s reporting and evidence provided to the court was thorough, clear, compelling and to the point and resulted in the client achieving a successful outcome.
I would recommend Air Environment for any matter involving the detailed analysis and interpretation of meteorological data and the development of atmospheric meteorological models.
Nice work!
Andrew and the team proved to be very flexible and responsive in accommodating changes and providing strategic and technical advice. I would highly recommend Air Environment and will certainly use them again.
Our Brisbane Odour Laboratory holds NATA accreditation to ISO/IEC 17025 for laboratory operations and AS EN 13725 for olfactometry test methods.
Laboratory results are an input, not an answer. Our air quality consultants can take the numbers through modelling, assessment and management planning with the same team.
Common questions about dynamic olfactometry, sampling logistics, panel management and what laboratory accreditation actually buys you.
A sample of odorous air is presented to a trained human panel through an olfactometer, diluted with odour-free air in controlled steps. The dilution factor at which half the panel can just detect the odour is the odour concentration, reported in odour units per cubic metre. It remains the reference method because the human nose still detects many odorous compounds at concentrations well below the limit of routine chemical analysis.
One odour unit per cubic metre (ouᴇ/m³) is the concentration at the panel detection threshold. A sample reported at 4,000 ouᴇ/m³ needed to be diluted 4,000 times before half the panel could just detect it. The figure feeds directly into dispersion modelling as an emission rate, which is why sampling and analysis quality determines the quality of every impact prediction downstream.
AS EN 13725 requires analysis within 30 hours of collection, because odorous compounds degrade and react inside the sample bag. That window drives project logistics more than anything else, and it is the single most common reason samples are rejected. Sampling schedules should be planned backwards from the panel session, not forwards from site access.
Samples are drawn into inert bags using the lung principle, where a vacuum chamber pulls the sample into the bag so it never passes through a pump. Bag material and all wetted parts are selected to avoid adsorption and carryover. Our olfactometer uses PTFE and passivated 316L stainless steel throughout, with heated lines and jet pulse cleaning between samples.
Panel members are screened against a reference gas and must fall within the sensitivity range the standard allows, with ongoing performance monitoring across sessions. Assessors outside the range are excluded. Panel management is the part of olfactometry most often done poorly, and it is where reproducibility is won or lost.
Concentration tells you how much dilution is needed before the odour disappears. Intensity describes how strong it seems above that threshold. Hedonic tone describes how pleasant or unpleasant it is. Two sources at the same concentration can generate very different complaint rates, so where community response matters, concentration alone rarely explains what is happening.
Yes, provided sampling method, bag type and collection time are documented and the 30-hour window can be met. We will tell you before analysis if the chain of custody has a gap that would weaken the result, rather than after.
Yes. Our Brisbane Odour Laboratory holds NATA accreditation to ISO/IEC 17025 for laboratory operations and AS EN 13725 for olfactometry test methods. Accreditation is what allows results to be relied on in regulatory submissions and contested proceedings.
Yes. We deliver air consulting services across Australia, including regional and remote sites. Sampling logistics are scoped around the 30-hour analysis window, which usually determines how a remote campaign is staged.
