ODOUR MEASUREMENT: HOW TO MEASURE ODOUR
At Silsoe Odours, we provide our clients with information about the odorous emissions produced by your processes. We can objectively measure, assess and analyse odours, all in line with international odour measurement standards. So the question is, how do we do this?
HOW TO MEASURE ODOUR
Generally speaking, we use two methods of odour measurement.
Most commonly, we measure odour by taking samples from a site and analysing them in our UKAS-accredited odour laboratory, using dynamic olfactometry. This is called an odour sampling survey. Our analysis results help you to understand the scope and the characteristics of odour emissions at your site. You will find this useful for planning purposes, to comply with environmental permits or in testing odour abatement equipment.
For the second route, we send odour panellists to conduct a ‘sniff test’ of the area.
ODOUR MEASUREMENT EQUIPMENT: Sampling
Have you ever heard the mantra “proper preparation prevents poor performance”? Here at Silsoe Odours, we are fully on board with the ‘5Ps’. That is why we begin every single odour measurement project by thoroughly researching the site. We take into account meteorological and physical conditions for the day of the survey. For sampling surveys, we also carefully identify the potential odour sources.
Equally important is that our team holds extensive expertise and experience. Crucially we hold UKAS-accreditation for odour sampling and testing.
Finally, it is essential that we use the right odour measurement equipment. We carefully select the right tools for each job. Here is a quick run-down of some of the equipment we use.
Nalophan Odour Sampling Bags
When we are at a site, we collect odour samples using Nalophan odour sampling bags. We manufacture and test the bags in-house at our laboratory according to the requirements of European odour standard EN13725. Indeed we are accredited to do so, according to ISO17025.
Rigid Lung Barrels
Where there is positive pressure, we will attach the Nalophan odour sample bag to direct point sources. Otherwise, we use a rigid lung barrel to evacuate the air using a vacuum pump, to draw the odour sample into the bag.
A Lindvall hood is a piece of equipment that allows us to measure odour from open sources. We place the hood over a particular source and allow it to fill. Once complete, we can draw off the odour from the hood using a Nalophan sample bag and rigid lung barrel.
Sometimes we may need to dilute a sample at the source in order to stop condensation forming. In this case, we will use a dilution probe. When we prevent condensation forming, we can ensure more effective odour measurement.
ODOUR MEASUREMENT EQUIPMENT: Testing
Once we have successfully collected odour samples, we return them to our laboratory to undergo testing and analysis. To do this, we use a process of dynamic olfactometry.
The only effective sensor of odour is the olfactory organ. In other words, the human nose! For that reason, we consider it our most critical piece of odour measurement equipment. We use a panel of carefully selected, screened and trained assessors (‘odour panellists’) to conduct our olfactometry testing.
Specialist odour panellists also conduct ‘sniff surveys’.
The olfactometer is a device that dilutes an odour sample to a known concentration. We then use the olfactometer to present the sample to our specialist odour panel. The odour panellists then take part in a ‘forced choice’ progression of odour assessment until they have established the odour concentration of the sample. In addition to odour concentration, we can also test samples for chemical analysis, odour detection threshold, odour intensity and odour characterisation.
FIND OUT MORE ABOUT ODOUR MEASUREMENT
So you should now have a good idea of what goes into measurement odour, from preparation to collection to analysis. However if you have any queries we would be more than happy to help. Our team have many years of expertise and experience and can help with your specific odour challenge. In the first instance, you can reach us by calling 01525 860222 or by clicking the button below. You can also follow us on LinkedIn, Twitter and Facebook to keep up with the latest news from the team.