Introduction
Healthy buildings start with healthy air. Indoor air quality (IAQ) monitoring is essential for achieving green building certifications and creating sustainable indoor environments.
While the benefits of IAQ sensors seem clear – from tracking pollutants to optimizing ventilation – many projects face feasibility concerns. This article examines the true value of IAQ sensors, their budgetary implications, and their role in earning crucial points for WELL, BREEAM, and LEED.
WELL, BREEAM, and LEED Certifications: Different Approaches to Indoor Air Quality Sensors
WELL, BREEAM, and LEED represent leading green building certifications, each with its own unique perspective on indoor air quality (IAQ) and the role of sensor technology.
While all three recognize the importance of healthy indoor environments, they differ in their specific requirements and recommendations regarding IAQ monitoring. This section will explore these varying approaches, outlining how each certification incorporates IAQ sensors, the specific parameters they prioritize, and the potential benefits for projects seeking certification.
WELL certification: a focus on occupant well-being
The WELL certification is one of the leading sustainable building certifications, driven by cutting-edge technologies. Its emphasis on the health and wellness of building occupants makes the integration of IAQ sensors a strategic element for buildings aiming to achieve this certification. Air quality monitoring devices benefit from the following features:
- A01 Air Quality Feature (Precondition)
- A08 Air Quality Monitoring and Awareness (2 points)
- Thermal Performance (Precondition)
- Thermal Comfort Monitoring (1 point)
- T07 Humidity Control (1 point)
Beyond the points awarded, the installation of IAQ devices greatly streamlines the ongoing data submission and recertification process, ensuring the continued maintenance of the certification.
Somewhere link to “how to select the right IAQ sensor for your green Building Project”
LEED v5 certification: the evolution towards continuous monitoring
The recently announced updates to LEED v5 are a clear example of how quickly innovative solutions are becoming part of the certification process. If in previous generations of LEED certification, continuous air quality monitoring was not a priority, then in the new version, this concept has been rethought. In the new protocol, The permanent air quality measurement devices should cover at least Carbon dioxide (CO2), Particulate Matter (PM2.5), Total Volatile Organic Compounds (TVOCs) and Comfort Parameters (T oC and RH %), which is an obvious vector for industry development in the coming years.
BREEAM certification: optimizing ventilation with CO2 sensors
As of 2025, BREEAM certification does not include the installation of air quality measurement sensors in its certification guidebook. However, the Health and Wellbeing chapter, specifically part 02 on Indoor Air Quality, recommends integrating CO2 sensors with a building’s ventilation system. This approach helps optimize ventilation and transition to a smart ventilation system.
Conclusion
WELL
Yes, IAQ sensors are a strategic element
LEED
Continuous air quality monitoring was not a priority in previous generations of LEED certification, then in the new version, this concept has been rethought.
BREEAM
No, IAQ measurement sensors are not included in its certification guidebook as of 2025.
WELL
Health and wellness of building occupants
LEED
The permanent air quality measurement devices.
BREEAM
Optimizing ventilation and transitioning to a smart ventilation system.
WELL
Particulate Matter: PM2.5 (15 μg/m3) and PM10 (50 μg/m3)
Organic Gases: Benzene (10 μg/m3), Formaldehyde (50 μg/m3), Toluene (300 μg/m3)
Total VOCs: 500 μg/m3 (for continuous monitoring)
Inorganic Gases: Carbon monoxide (10 mg/m3 or 9 ppm), Ozone (100 μg/m3 or 51 ppb)
Radon: 0.15 Bq/L or 4 pCi/L
Carbon dioxide (CO2)
LEED
Carbon dioxide (CO2)
Particulate Matter (PM2.5 and PM10)
Total Volatile Organic Compounds (TVOCs)
Temperature and Relative Humidity
Carbon monoxide (CO)
Ozone (O3)
BREEAM
Total Volatile Organic Compounds (TVOCs)
Formaldehyde
Carbon dioxide (CO2)
BREEAM also emphasizes ventilation design and filtration efficiency based on outdoor air quality levels
WELL
Streamlines data submission and recertification process, ensuring continued maintenance of certification
LEED
N/A
BREEAM
Helps optimize ventilation and transition to a smart ventilation system.
WELL
- A01 Air Quality Feature (Precondition)
- A08 Air Quality Monitoring and Awareness (2 points)
- T01 Thermal Performance (Precondition)
- T06 Thermal Comfort Monitoring (1 point)
- T07 Humidity Control (1 point)
LEED
N/A
