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Air quality testing service

Air Quality Page Description

The quality of air in both indoor and outdoor environments is critical to the health, comfort and well-being of people using them.

Air Quality Details

Air quality testing

BRE provides a wide range of air quality testing and advisory services to ensure that the air in and around your buildings is of optimum quality and meets regulatory and environmental requirements.

Why work with BRE?

BRE’s technical experts have extensive experience and knowledge of monitoring and assessing across a wide range of indoor environments. We offer a flexible approach to testing with a variety of work patterns and testing protocols available to suit your organisation.

Our reports provide you with impartial findings and assurance, allowing you to commission testing of the air within an indoor space, or to demonstrate the safe and effective operation of an air treatment/cleaning product carried out in a real-life environment.

Our services include monitoring air quality, minimising outdoor air pollution impacts, investigating pollutant emissions, measuring ventilation improving indoor air quality and testing of monitors and air cleaning devices.

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Preparing indoor air quality plans to assist the client to fulfil the requirements of various environmental assessment and building certification schemes.

Identifying and measuring TVOC and/or formaldehyde emissions from building components, materials, paints, office equipment and furnishings. The measurements can be carried out to show compliance with environmental assessment schemes (including BREEAM, LEED and WELL) as well as regulations and European standards such as the French Arrêté scheme. We have room-sized chambers (including a 30 m3 room conforming to EN 16516) and smaller cells (including FLEC, which conforms to ISO 16000-10) available.

Responding to indoor air quality concerns or complaints, our expert team conducts third-party investigations in a wide range of building types (e.g. dwellings, schools, hospitals, workplaces), delivering clear and unbiased reports. Inspection and assessments are backed up with monitoring, sampling and analysis of the air for a range of air pollutants. We can identify possible sources of any pollutants found and suggest remedial actions.

Using tailored testing regimes in our environmentally controlled chambers, we can replicate various indoor settings and conditions. This allows us to study the impact of activities including for example cleaning, cooking, vaping and smoking on indoor air quality.

Validation of the accuracy of air quality monitors and sensors by subjecting them to controlled, known environmental and air quality test conditions. This will benefit manufacturers and end-users by increasing their confidence in the quality of the data that the sensors/monitors generate.

Assessment of the effectiveness of air cleaners and purifiers using controlled environmental chambers. Such devices and technologies can be challenged with a variety of airborne pollutants to ensure that they perform effectively. Also, assessment of the safety of such devices by checking for unwanted and potentially harmful emissions such as ozone or by-products such as formaldehyde during their operation.

Bespoke monitoring and testing according to customer needs, using  environmental chambers or purpose-built mock-ups of rooms or other indoor areas. Also, air quality testing in other enclosed environments, such as vehicles and temporary structures.

Helping to ensure that the ventilation present in buildings of all types  contributes to optimum quality indoor environments, while making efficient use of energy and complying with Building Regulations (Approved Document F) and/or environmental  assessment schemes (e.g. BREEAM).

Measuring air pollutants, including gases, particles and volatile organic compounds (VOCs), to demonstrate compliance with health-related and building certification schemes (e.g. BREEAM, WELL, LEED).

Case study: Investigating a school’s indoor air quality

Case study: Investigating a school’s indoor air quality

Following feedback from the staff at a new build school, BRE was commissioned to evaluate the environmental conditions in the school. We carried out comprehensive four week programme of surveys, inspections, monitoring and testing to investigate the factors that may have led to ill health among building occupants, assess occupant comfort, and establish whether the school building complied with Building Regulations and contractual and statutory air quality requirements.
The programme included:

  • Thermal comfort assessment (temperature and relative humidity)

  • Inspection of heating and air handling systems (including controls)

  • Air quality monitoring (CO, CO2, particulate matter, SO2, NO2, VOCs, formaldehyde)

  • Airtightness and air change rate measurements

  • Lighting assessment (daylight; electric lighting; glare; task-based lighting)

  • Background noise assessment

The findings were presented in a full technical report, and later in person to senior educational officers at the local authority. The main findings and recommended remedial actions were also presented in layman’s terms to school staff and to maintenance staff working for the school’s contracted facilities management organisation. This included guidance on use of features such as trickle vents and Heating Ventilation Air Conditioning controls.

BRE was later commissioned to undertake follow-up monitoring to verify that the remedial actions had been effective.

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BRE can assess the effectiveness of air cleaners and purifiers in our variety of controlled environmental chambers (with internal volumes of 1 m3, 30 m3 and 40 m3). Devices can be challenged with a variety of airborne pollutants, such as particles, gases and volatile organic compounds, to ensure that they perform effectively.

The safety of these devices, in checking for unwanted and potentially harmful emissions such as ozone or by-products such as formaldehyde during their operation, can also be evaluated.

Showcase: Air purifier testing for airborne particle removal
BRE challenged a commercially available, fan-driven, free-standing filtration device with generated ultrafine (0.02 to 1 µm) particles under controlled conditions in its 40 m3 environmental chamber. The filtration unit was run at different air flow rate settings and also compared against the natural decay rate of particles in the chamber (without the filtration unit operating) once the particle generator was turned off.
Understanding the performance of these devices is important to achieve optimum indoor air quality conditions, balancing filtration performance, energy use and noise produced at different fan settings.

  • Normalised ultrafine particle concentrations 
  • Flow rate A = 85 m3 h-1
  • Flow rate B = 200 m3 h-1
  • Flow rate C = 430 m3 h-1


Time for particle concentration to reduce to 10% of original level:

Filtration unit flow setting

Air flow rate (m3 h-1)

Time to 10% of particle concentration (mins)













Indoor air quality (IAQ) is increasingly recognised as a major concern, potentially affecting both the health and productivity of building occupants. The design, refurbishment and maintenance of buildings are being increasingly driven towards the use of IAQ sensors to ensure the delivery of safe and productive indoor environments (Building Regulations Part F: Ventilation; BS 40102: Health and wellbeing and indoor environmental quality in buildings). As such, the availability and use of monitoring suitably accurate and reliable equipment (sensors and/or instruments) is increasingly important.

BRE tested a variety of types of carbon dioxide (CO2) sensors/instruments its 30 m3 controlled environmental chamber to evaluate their relative performances. Different concentrations were generated in the chamber using a controlled supply of CO2 gas from a cylinder. The results obtained were then compared against the readings from a reference monitor. All of the instruments used were within their current calibration period (as carried out by the manufacturer/supplier).

A number of the devices tested performed satisfactorily, as would be expected given the length of time that some CO2 sensors have been commercially available. However, at typical background CO2 concentrations some of the devices over-measured. At higher concentrations (1000 to 2000 ppm) two of the types of sensor tested under-measured CO2 concentration by approximately 60 to 80%.


% difference in measurements of background CO2 level compared to reference sensor

Showcase: Testing of carbon monoxide (CO) monitoring instruments
BRE tested three types of carbon monoxide monitoring instrument in one of its controlled environmental chambers to evaluate the consistency of their responses between ‘identical’ units of the same type. All the instruments used were within their current calibration period, as carried out by the instrument manufacturer/supplier.

Two sets of tests were undertaken. A stable concentration of approximately 50 to 60 ppm of CO was set up in the chamber and allowed to stabilise over a period of approximately 3 hours. The actual concentration of CO in the chamber was also measured/confirmed using a reference instrument approved to the U.S. EPA, UK Environmental Agency and EU Environmental Agency standards. 
The different sets of equipment were co-located together as closely as was practically possible within the test chamber during the testing. It can be seen from the results obtained that some of the types of instrument had much greater levels of accuracy and precision than others.

From the results obtained, it can be seen that one of the instrument types (denoted by circular symbols) showed very good agreement between the (seven) units tested. However, one of the instrument types (denoted by square symbols) showed very poor agreement between the (eleven) units tested, with measured concentrations of CO varying by a factor of up to approximately two.

Showcase: ‘Green technology device’ testing
BRE challenged a ‘green technology’ air purification device with various air pollutants under controlled conditions in one of its environmental chambers. The device drew room air both over plants, and also through the growing medium of the plants.
The ‘green technology device’ had no effect on carbon dioxide concentrations in the test chamber and a slight beneficial effect on ultrafine particle (0.02 to 1 µm) concentrations. Nitrogen dioxide, a reactive atmospheric gas, concentrations were significantly reduced in the chamber when the device was operated.

Indoor environmental quality training

Indoor environmental quality training

Learn about the background, scope, and features of the Indoor Environmental Quality standard, BS 40102-1. This standard offers guidelines for monitoring and reporting IEQ and well-being in occupied buildings.

BRE Academy IEQ online course

Get in touch

Get in touch

For more information, call us on +443333218811, email us at or use the online form.

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