In France, people spend an average of 80 to 90% of their time indoors: at home, at the office, at school, or in shops. Indoor air quality therefore has a direct impact on quality of life, public health, and building performance. According to an exploratory study conducted in 2014 by Anses (the French Agency for Food, Environmental and Occupational Health & Safety) and the French Indoor Air Quality Observatory (OQAI), regularly cited by public authorities, indoor air pollution is estimated to cost close to €19 billion per year in France in health and economic terms.
Faced with this reality, local authorities, landlords, and facility operators are increasingly turning to the Internet of Things (IoT) to continuously measure, understand, and correct indoor air quality, in support of a smart building and smart city genuinely driven by data.
This issue is no longer just a matter of comfort: it is now governed by precise regulatory obligations, which connected sensors and an indoor and outdoor air quality IoT platform like Kuzzle make it possible to meet reliably, automatically, and traceably.
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Indoor air quality (IAQ) refers to all the physical, chemical, and biological characteristics of the air breathed inside a building, and its impact on the health and comfort of occupants. It depends on several combined factors: air renewal (ventilation, airing), indoor pollution sources (materials, furniture, human activity, combustion appliances), and outdoor pollution that infiltrates the building.
Contrary to popular belief, indoor air is often more polluted than outdoor air, due to the confined nature of indoor spaces and the multiplication of emission sources. This is why indoor air quality is now considered a quality-of-life criterion in its own right, on a par with thermal or acoustic comfort, and an indicator closely tracked in building and sustainable connected territory strategies.
The main indicators tracked as part of indoor air quality monitoring are:
To date, formaldehyde and benzene are the only two pollutants for which a regulatory guideline value is set out in the French Environmental Code (article R221-29, from decree no. 2011-1727 of 2 December 2011): it has been set at 10 µg/m³ for formaldehyde since 1 January 2023, and at 2 µg/m³ for benzene since 1 January 2016. Limit values that trigger a mandatory expert assessment if exceeded are also set at 30 µg/m³ for formaldehyde and 10 µg/m³ for benzene. The other indoor air quality guideline values, including that for CO2, serve as a reference for regulatory monitoring and measurement campaigns, without being binding values written into the Code.
Monitoring indoor air quality in certain buildings open to the public (known as "ERP" under French regulations) is governed by the French Environmental Code, Section 5 "Indoor Air Quality," and more specifically by Subsection 3 "Monitoring indoor air quality in certain buildings open to the public," articles R221-30 to D221-38. This framework was set out in detail by decree no. 2015-1000 of 17 August 2015, then simplified by a scheme that came into force on 1 January 2023 (often referred to as RSDIA, the indoor air quality monitoring regulation).
The regulatory scheme rests on four obligations, borne by the owner or operator of the premises:
Facilities concerned notably include childcare facilities for children under six, nursery and elementary schools, and secondary-level education or vocational training establishments, as well as leisure centers, since 1 January 2023. Social and medico-social establishments, along with facilities housing minors under judicial protection, have been subject to the requirement since 1 January 2025.
In parallel, the Tertiary Decree (known as "éco-énergie tertiaire") requires a progressive reduction in energy consumption for commercial buildings larger than 1,000 m², with declarations made on Ademe's OPERAT platform. The BACS Decree (Building Automation and Control Systems), revised at the end of 2025, complements this scheme by making it mandatory to install a Class A or B building management system (BMS) (standard NF EN ISO 52120-1) in commercial buildings where the capacity of heating, ventilation, and air conditioning systems exceeds certain thresholds. This obligation to monitor, record, and automatically regulate energy and environmental data makes IoT an almost essential tool for any building or smart building seeking to secure its compliance.
| Deadline | Facilities concerned | Main obligation |
| 1 January 2018 | Childcare facilities for children under 6, nursery and elementary schools (first wave) | First pollutant measurement campaigns |
| 1 January 2023 | All schools, secondary education establishments, leisure centers | Annual ventilation assessment, self-assessment, measurement campaigns |
| 1 January 2025 | Social and medico-social facilities, facilities for minors (judicial protection) | Extension of the indoor air quality monitoring scheme |
| 1 January 2025 (buildings > 290 kW) / 1 January 2030 (70-290 kW) | Commercial buildings (offices, retail, healthcare, education, heated/air-conditioned warehouses) | BACS Decree: mandatory BMS, hourly consumption monitoring |
Meeting regulatory obligations and genuinely improving occupants' quality of life requires building a coherent IoT chain, from the sensor through to actionable data. Three technology building blocks must be considered together: sensors, the transmission network, and the supervision platform, as illustrated by the various IoT use cases for buildings and connected cities already deployed in the field.
Indoor air quality sensors continuously measure one or more parameters: CO2 (non-dispersive infrared sensors, NDIR), VOCs (formaldehyde, benzene) via electrochemical or photoionization sensors, fine particulate matter via laser scattering, as well as temperature and relative humidity. The choice depends on the building: a school will favor robust, low-cost CO2 sensors that can be deployed in large numbers, while a commercial building or data center will look for multi-parameter sensors that are precise and can be integrated into the building management system.
The choice of network determines the battery life, range, and cost of the IoT solution:
Deploying more sensors without a supervision platform simply means multiplying spreadsheets and isolated alerts. A centralized IoT platform such as Kuzzle makes it possible to collect heterogeneous data streams, keep a history of them, trigger action scenarios (alerts, automatic activation of ventilation, notification of technical teams), and provide a consolidated view to operators, local authorities, and, where relevant, occupants. This is the software layer that turns a simple indoor air quality measurement into a tool for managing the building and the city.
| Layer | Role | Example technologies | Point of attention |
| Sensors | Measuring CO2, VOCs, fine particulate matter, temperature, humidity | NDIR, electrochemical, laser | Accuracy, calibration, battery life |
| Network | Carrying data from the sensor to the platform | Wi-Fi, LoRaWAN, Zigbee, NB-IoT/LTE-M | Range, power consumption, cost per sensor |
| Platform | Centralization, analysis, automation, reporting | Kuzzle real-time IoT platform | Interoperability, scalability, data sovereignty |
Kuzzle designs IoT platforms for the smart building and IoT platforms for the smart city, in support of sustainable connected territories. Indoor and outdoor air quality monitoring is explicitly one of the IoT use cases covered by the platform, alongside energy management, building management, and smart street lighting: all complementary building blocks for managing a building or a connected territory as a whole, rather than treating air quality as a standalone issue.
Kuzzle's air quality solution collects CO2, temperature, and humidity data indoors, as well as fine particulate matter (PM10/PM2.5), volatile organic compounds, and ozone outdoors, via sensors connected through LoRaWAN, NB-IoT, Wi-Fi, or Sigfox, presented as interactive dashboards. It primarily targets schools and childcare centers, cities and municipalities, healthcare facilities, offices, shopping centers, and industrial areas, with four intended benefits: a positive effect on health (fewer respiratory illnesses and allergies), compliance with environmental and regulatory standards, savings through optimized heating and air conditioning, and better responsiveness thanks to automatic alerts when a threshold is exceeded.
Kuzzle Hypervision is the multi-domain supervision layer of the Kuzzle ecosystem: it cross-references data from IoT sensors (including air quality sensors), business systems (BMS, CMMS, GIS), and building or territory reference data within a unified interface. In practice, this makes it possible to:
Kuzzle's modular architecture, combining Kuzzle Data, Kuzzle IoT, and Kuzzle Hypervision, makes it possible to connect air quality sensors to all the building's other data streams (energy, occupancy, lighting) without replacing tools already in place, with sovereign French or on-premise hosting available for public and private organizations that care about controlling their data.
Kuzzle documents several concrete deployments related to air quality and the connected building. In Noisy-le-Grand, a one-year pilot made it possible to deploy indoor air quality sensors in the city's primary schools while staying within the project's initial budget, and reducing the energy consumption of the buildings concerned.
The speed at which the platform can be deployed is also demonstrated in other IoT use cases: the Bouygues Construction case study shows that a geolocation solution covering more than 50,000 pieces of equipment across 1,000 construction sites, integrating more than 20 connectivity technologies, was brought into production in one week thanks to Kuzzle IoT. This same rapid-integration logic applies to indoor air quality: an operator of school or commercial buildings can connect its existing CO2 and VOC sensors, centralize the data in Kuzzle Hypervision alongside the energy monitoring required by the BACS Decree, and thereby have a reliable, traceable data history to support the steps expected under the indoor air quality monitoring regulation (RSDIA).
What is the difference between indoor air quality and outdoor air quality? Outdoor air quality is measured by approved air quality monitoring associations (AASQA) at the scale of a territory, whereas indoor air quality concerns the air breathed inside a specific building, which is often more polluted due to confinement and emission sources specific to the building and its uses.
Which buildings are subject to the indoor air quality monitoring requirement? Since 1 January 2023, childcare facilities for children under six, schools, and secondary education establishments, as well as leisure centers, have been covered. Since 1 January 2025, the requirement has extended to social and medico-social establishments and facilities housing minors under judicial protection (French Environmental Code, articles R221-30 to D221-38).
Is one IoT sensor enough to comply with indoor air quality regulations? No. The regulation requires an annual assessment of ventilation means, a self-assessment every four years, measurement campaigns, and a documented action plan. IoT sensors facilitate continuous data collection (particularly CO2) but must be paired with a platform capable of storing, presenting, and tracing this information in order to meet the obligations to report to occupants and authorities.
How does IoT contribute to quality of life in a smart building? By making previously invisible parameters visible in real time (CO2, VOCs, fine particulate matter, humidity), IoT makes it possible to act before discomfort or health risks set in: adjusting ventilation, alerting technical teams, informing occupants. This is one of the pillars of the smart building, on a par with energy management or space occupancy management.
What is the link between indoor air quality and the BACS Decree or the Tertiary Decree? The BACS Decree requires a BMS capable of automatically monitoring, recording, and regulating a commercial building's technical data, while the Tertiary Decree sets energy reduction targets declared on the OPERAT platform. An IoT platform that centralizes both air quality data and energy data, such as Kuzzle Hypervision, makes it possible to meet both requirements with a single data collection and supervision infrastructure.
Does Kuzzle offer a turnkey air quality measurement solution? Kuzzle does not manufacture sensors but provides the IoT and air quality supervision platform (Kuzzle Data, Kuzzle IoT, Kuzzle Hypervision) that connects the air quality sensors of a building or territory, centralizes their data alongside other data streams (energy, occupancy, lighting), and automates the associated business scenarios, with sovereign French or on-premise hosting depending on the organization's needs. Interested organizations can request a Kuzzle demo to evaluate the solution on their own building portfolio.