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Odour monitoring is an important part of ongoing best practice for odour


We know that many people stumble across odour monitoring at the direction of third parties. This might be the regulator, the planning authority, or a specialist consultant like an architect or legal counsel. So, we put together a comprehensive overview to help you get started. We explain why odour monitoring is so important and what the benefits could look like for you. We also look at the different odour services available to you and which would support your needs most effectively. To start with, there are three key questions for you to think about.

  • Why is odour monitoring important?

  • Why do I need to monitor odour?

  • Which odour services are best for me?


As we said above, odour monitoring is something that you might be thinking about because you have to. You might have received odour complaints. Or perhaps you have received advice from the regulator or planning authority.

Businesses usually have an odour condition in their environmental permit. This means that you are probably already in breach of your permit by the time you notice a problem. The same is true for planning applications. You will likely need to provide evidence that you have considered odour. Missing this step means you will probably face frustrating delays somewhere along the line.

Thinking about odour monitoring early will save you time, money and effort later.

In the future, the key is to make odour monitoring a key part of your daily best practice. In doing so, you will always have the facts to hand. As a result, you can fix any problems before they escalate.


In the first place, it is important to think about what you are trying to achieve. This will help shape the approach you take. Generally speaking, there are three main reasons you might be looking into odour monitoring.

1. Planning

Planning applications will usually require evidence of suitable odour monitoring and considerationYou may be in the planning stages and need to consider your development’s potential odour impact. Local authorities often require evidence of odour monitoring as standard when they consider planning applications. What’s more, if you neglect odour in your planning, you may face legal repercussions later. This could happen if there is a negative impact on residents or the neighbouring community.

As a starting point, you could look at the Air Quality section of the National Planning Practice Guidance and the IAQM Guidance on assessment of odour for planning.

2. Ongoing Best Practice

Regular monitoring of the site is best practice and may form part of your environmental permitYou may wish to monitor how effective your odour control measures are. This will help you avoid problems before they arise or fix them in the early stages. You may also nominate specific staff members to monitor the perceived odour around your site. Regular monitoring should form part of your best practice measures and may be an odour condition in your environmental permit.

The Environment Agency offers comprehensive advice on how to comply with your environmental permit in their H4 Odour Management guidance.

3. Complaints Management

Your goal may be to understand an existing problem, perhaps in response to nuisance complaintsYour goal might be to understand an existing odour problem, perhaps in response to nuisance odour complaints. You can use this knowledge to improve your odour management plan. Or where cases progress to court to demonstrate an effective response to complaints. Being proactive and invested can also be helpful when you’re engaging with the community affected by any odour issues.


Odour Sampling & Measurement

Ideally, you will use a combination of regular sampling and measurement as part of your ongoing activity. It will form part of your ‘best practice’ odour monitoring and should be included in your odour management plan. The goal here is to identify which of your processes are performing well and where you might need to act. If you do this regularly, you are unlikely to encounter major problems before you have an opportunity to fix them. What’s more, if you monitor odour regularly, you can provide evidence of your permit compliance to the regulator.

Needless to say, it is not always practical to monitor odour as a matter of course. And sometimes, issues crop up despite your best efforts. If you find yourself in receipt of nuisance complaints, you can use sampling and measurement to confirm whether the complaints are valid. You will have detailed data to support your findings, which can be useful for the regulator and during legal proceedings later on.

At Silsoe Odours, all our odour sampling and measurement is UKAS-accredited. We can assess samples for several things. The most popular measurements we conduct are for odour concentration, intensity and characterisation. However, we can also look at chemical analysis, odour detection threshold and hedonic tone.

‘Sniff Survey’ Odour Monitoring

Sniff surveys can be carried out by internal staffAnother useful way to monitor odour is with ‘sniff surveys’. Our specialist team of odour panellists will conduct a survey to monitor the impact of your odour sources in the surrounding area. The most effective measure of odour is the human nose. These surveys are great if you need to monitor the odour source but don’t have access to the site or there is more than one potential odour source.

Odour Sensitivity Testing – for ongoing monitoring

You can attend our Covid-compliant laboratory for odour sensitivity testing.As with sampling and measurement, it is important to build regular odour monitoring into your daily best practice activity. Try to allocate this responsibility to a few specific staff members for better consistency in your results. You will find it helpful to have this in place to show good practice to the regulator. It is even better if the monitoring staff comply with the European odour standard BSEN13725:2003. You can ensure this with odour sensitivity (or acuity) testing. This is a quick, cost-effective session in our UKAS-accredited laboratory in Bedfordshire. Your staff members will gain valuable insight into their individual sensitivity to odour compared to the general population.

Planning Surveys

If you are working on a new development, whether residential or industrial, you will need to support your planning application with an odour risk assessment. You will need to account for any potential odour impacts on residents or the neighbouring area. Planning law aims to monitor possible odour impacts at the first opportunity. This is to make sure they don’t become a problem for the development and nearby community once complete.

You will be especially interested in paragraph 182 of the National Planning Policy Framework, which reads:

Planning policies and decisions should ensure that new development can be integrated effectively with existing businesses and community facilities (such as places of worship, pubs, music venues and sports clubs). Existing businesses and facilities should not have unreasonable restrictions placed on them as a result of development permitted after they were established. Where the operation of an existing business or community facility could have a significant adverse effect on new development (including changes of use) in its vicinity, the applicant (or ‘agent of change’) should be required to provide suitable mitigation before the development has been completed.

Dispersion Modelling

In a similar way to planning surveys, you will find dispersion modelling useful at the planning stages of a new or modified development. You will get a mathematical model, usually based on odour sampling survey results. It will show how odours from your proposed developments are likely to impact the surroundings. Or conversely, how an existing odour source may affect your housing development. Dispersion modelling is also handy to test the projected efficiency of different odour abatement equipment types.

Smoke Testing

Smoke testingA key aspect of odour control often includes ‘odour proof’ buildings and containers. It is good practice to monitor these structures to ensure no weak points where odour might escape. Equally, if you know you have a leakage point but cannot identify it, you will find smoke testing useful. Our team of odour specialists fill your building or container with visible oil vapour ‘smoke’. They will then be able to see exactly where that smoke emerges. You can use this insight to take remedial action and monitor the leakage sites for any future odour escape. This is particularly useful in identifying leakage from room to room.


So whatever your goal, when it comes to odour monitoring, we can support your needs wherever you are in the UK. We operate independently and have a small but experienced team of odour experts. The Silsoe Odours team holds UKAS accreditation for all our odour measurement and sampling. Give us a call on 01525 860222 or click below to get in touch with our team. We are happy to talk through any query and advise you on the best solution for your needs.