WHAT IS A SNIFF SURVEY ?
A sniff survey is an independent subjective survey that measures the impact of odours. Known by many names, you may also see it referred to as a sniff test, odour survey or field odour survey. It identifies the specific odour source, or sources, where it is not known.
At Silsoe Odours, we use the results of this type of odour survey to provide clients with scientific evidence relating to your odour emissions. Our report will enable you to measure, evaluate and ultimately control the odours which your plants and processes may produce.
Our sniff surveys are conducted by qualified odour panellists, in line with BSEN16842-2 guidelines. They determine the effects of odour dispersal over a determined period in a range of meteorological conditions.
HOW DO SNIFF SURVEYS ASSESS ODOUR IMPACT?
Sniff surveys use a series of observation points located downwind of the suspected source of the odour. Panellists keep detailed records to track intensity and frequency. The term ‘plume’ describes the trajectory of the odour and the dispersal pattern created as it meets atmospheric turbulence. We record data at regular intervals, noting meteorological divergences. Our human assessors use the ‘sniff test’ to determine the absence or presence of the odour, and its journey is plotted by noting where the smell is at its most intense and at what point it disappears.
The composition of the panel for any given odour survey will remain constant throughout the testing process, and the manner of assessment will determine the number of panellists:
Plume Method – a minimum of five assessors.
Dynamic Plume Method – a minimum of two assessors.
The simplified diagram in Fig. 1 illustrates the idealised progression of the assessors. The wind indicated by the arrow 1, the odour source is at 2. Black spots indicate where an odour is detected and circles where no odour is detected. The plume extent is drawn between odour present and no odour points. Panel members will make an assessment every 10 seconds.
Don’t take our word for it – here’s what our clients say:
We were seeking planning permission for a development which is adjacent to a site with known odour issues. We had completed our own survey, but the council asked for an independent odour assessment. We approached Silsoe Odours as had previously had a good experience with them for olfactometry work, and knew they had prior knowledge of the site. I was particularly impressed with the way they presented and summarised their data. It was easy to understand and presented in such a way that the layman could understand. I wouldn’t hesitate to recommend Silsoe Odours and look forward to working with them again in the future.
Peter Brett Associates