THE MANY NAMES OF SNIFF SURVEYS

Do you know what sniff surveys are? For starters, they have a fair few names. So, depending on who you ask, you may hear it called a ‘field odour survey’, ‘field odour impact survey’, ‘odour survey’, ‘sniff test’, or – as we favour – a ‘sniff survey’.

Either way, it is a subjective survey that measures odour impact. In sniff surveys, we use the human nose as an analytical sensor. Our trained odour panel can describe an odour’s frequency, character, duration and how offensive it is at a given point and time. We can also identify (or confirm) where an odour originates (the ‘odour source’).

WHY WOULD I NEED A SNIFF SURVEY?

Odour panel members, Catrin and Kim, on site conducting a sniff survey

There are a few reasons why you might find sniff survey data extremely useful. Specifically, you may use it to:

• overcome difficulties accessing the site of an odour source
• identify an odour source when there are multiple possible sources
• confirm the results of dispersion modelling
• design odour abatement equipment
• inform odour management plans
• validate odour complaints

OVERCOME DIFFICULTIES WITH ACCESS TO AN ODOUR SOURCE

One of the most frequent reasons clients ask us to conduct sniff surveys is for planning applications. In this instance, you need to demonstrate that your proposed development will not be impacted negatively by odour. You can assess the impact from nearby odour sources using sniff surveys, without needing access to those sources.

Our team of experienced odour consultants can advise when and where to survey. We will help you choose the best meteorological conditions (or, in other words, when the wind is blowing the right way) and identify which location points will gather the most representative data. You can read more about how we do this in the IAQM’s Guidance on the Assessment of Odour for Planning.

Finally, we will provide a comprehensive report, with maps and graphical representations showing the potential odour impact on your development.

IDENTIFY AN ODOUR SOURCE FROM MULTIPLE POSSIBILITIES

When odour becomes an issue in a community, there will probably be odour complaints. However, these complaints are not always accurately attributed. Sometimes, a site can be held responsible for odour nuisances caused by other sources. In these cases, sniff surveys can provide essential data to identify where the real issue lies. Usually, we will survey the area where complaints originate at different times of the day and week, factoring in differing wind directions. In this way, we can provide a clear picture of the origin of any odours.

SNIFF SURVEYS CAN CONFIRM THE RESULTS OF DISPERSION MODELLING

Dispersion modelling is a mathematical process which allows you to predict the impact of odour emissions. Often, you will use dispersion modelling to help you design new sites, or odour abatement equipment for existing sites. They can be beneficial as part of planning applications and environmental permit applications. You can also use dispersion modelling to provide an overview of the impact of odour based on your existing site. In this instance, you can conduct supporting sniff surveys to verify the modelling data, which provides confidence in the modelling before any physical development or remediation occurs.

DESIGN ODOUR ABATEMENT EQUIPMENT

When you understand the sources and extent of your odorous emissions, you can design effective abatement measures. You can equip your odour abatement equipment supplier with data from sniff surveys (and other kinds of odour monitoring). They will be able to interpret this data in order to design robust, effective and cost-effective equipment. It is essential to develop abatement equipment well to avoid rectifying problems later.

INFORM ODOUR MANAGEMENT PLANS

Usually, you will need to develop a comprehensive odour management plan as part of your environmental operating permit requirements. An odour management plan is a detailed document that outlines how you manage odour on your site. When creating this, you should consider the receptors near the area (schools, businesses, homes) and how your odour emissions impact them. Sniff surveys can provide the data you need to do this effectively. You can also use the data to demonstrate to the regulator that you have adequate and considered odour processes in place.

VALIDATE ODOUR COMPLAINTS

If you are an operator, odour nuisance complaints can be a real headache. Should your site receive too many (valid) complaints, the regulator could impose fines and restrictions (or even suspension) of your operating license. So, the first thing to do is confirm whether or not these complaints are, in fact, valid. Depending on the nature of your sites and the complaints you have received, you may wish to consider odour sampling, sniff surveys, dispersion modelling or a combination of different odour services. The data will help you understand where any problems lie and their extent. You can use this to resolve any issues and demonstrate your understanding of the situation to the regulator. Should odour nuisance complaints escalate to court, this data (and your response to it) will usually be considered favourably.

ASK US ABOUT SNIFF SURVEYS

Finally, please do give us a call if you are in the midst of any of the scenarios we have outlined in this article. We have a team of odour specialists and will be happy to answer any queries you have. In the first instance, you can reach us on 01525 860222. Alternatively, you can click the button below or email the team at info@silsoeodours.co.uk. So, please do get in touch!

Article updated 30th June 2022