Outdoor air pollution often dominates the news, but we spend much more time indoors than outdoors. If indoor air is not clean, it poses significant health risks. Without technological detection, we cannot know what pollutants are present in the air. Fortunately, with precise air quality monitoring devices and wireless IoT systems, it is possible to detect air quality and then purify the air using air filtration devices, creating a healthier environment. This article will introduce the development of indoor air quality monitoring technology and the related solutions offered by Nordic.
Wireless IoT technology helps create indoor air quality measurement and monitoring solutions
On average, a person inhales about 11,000 liters of air per day. According to the World Health Organization, approximately 6.7 million people die prematurely each year due to air pollution, with over 3.2 million deaths potentially attributed to indoor air pollution. According to the U.S. Environmental Protection Agency, Americans spend up to 90% of their time indoors. The National Institute of Environmental Health Sciences lists indoor pollution sources caused by human activities, such as smoking, burning solid fuels, cooking, and cleaning. Other sources include volatile compounds from building materials, equipment, and furniture, as well as biological contaminants like mold, viruses, or allergens.
Additionally, one of the most serious airborne threats to human health comes from VOCs (volatile organic compounds). They are widely used in paints, varnishes, cleaners, disinfectants, and solvent degreasers. The concentration of VOCs indoors can be ten times higher than outdoors and can lead to serious health issues.
Fortunately, IoT now offers a solution that can address potential dangers in a more detailed and timely manner, especially in cases of long-term, low-level pollution. Recent advances in wireless technology have helped create scalable solutions for measuring and monitoring indoor air quality. These advances allow for the flexible placement of various sensors independent of local IT networks. Combined with intelligent analytics, this data enables a better understanding of factors influencing indoor air quality.
By utilizing compact battery-powered sensors based on foundational IoT technologies such as Bluetooth LE, it is possible to sampling the air across an entire building. Meanwhile, low-power Wi-Fi technology is also a good choice for air quality sensors that take advantage of existing Wi-Fi infrastructure. Both technologies can transmit data to resource-appropriate Wi-Fi gateways, which can then forward the data to the cloud for remote access. Alternatively, a wide Bluetooth LE network can be constructed to send data to a cellular IoT gateway, which can forward data to the cloud independently of Wi-Fi, reducing security concerns.
Since wireless solutions do not require cabling, they can be easily integrated into new buildings or retrofitted into existing ones. Without physical wiring, sensors can be strategically placed with ease. For example, carbon monoxide sensors can be installed near fossil fuel heaters or in poorly ventilated rooms.
A key advantage of the new generation of sensors over traditional types is the continuous flow of data they provide, allowing for the identification of long-term air quality trends, leading to precise control. For example, based on historical data, additional air purification can be automatically triggered during summer when pollen counts are known to be high, or increased ventilation and heating can be triggered when cold and humidity conditions promote mold growth.
Edge computing capabilities enable today’s IoT devices to process continuous stream of data internally and only forward results to a smartphone, gateway, or cloud when action is needed to change humidity, temperature, ventilation, or purification. This greatly reduces energy consumption and data costs.
The IoT can be integrated with smart air purification, filtration systems, and intelligent HVAC (heating, ventilation, and air conditioning), enhancing flexibility. For example, when sensors detect carbon dioxide, VOCs, or other contaminants in the air, the integrated system can automatically intensify filtration.
Wireless air quality monitoring solutions enhancing educational environment quality
Many commercial wireless air quality monitoring solutions entering the market are showing positive results. For example, in New Zealand, research linking students' learning progress with the quality of their indoor environment led to the launch of the Te Haratau project by the New Zealand Ministry of Education. AirSuite, an intelligent environment solutions company, emerged from the Te Haratau project when the benefits of air cleaning applications became more apparent beyond the educational sector.
In 2023, AirSuite launched an indoor monitor designed to detect and record a range of environmental variables that may impact people's health and productivity in commercial, industrial, and residential environments. The AirSuite Glance uses a series of sensors to monitor carbon dioxide, VOCs, temperature, and humidity (as well as sound, light levels, and air pressure). By continuously monitoring a range of indoor environmental variables, it can improve health, boost productivity, and enhance employee retention — benefits that are crucial for any organization.
AirSuite utilizes the Nordic nRF52840 SoC to provide Bluetooth LE connectivity, transmitting data directly to users' smartphones every minute. It also integrates LTE-M or NB-IoT connectivity using Nordic's nRF9160 SiP to send relevant data to the cloud at least every 15 minutes. Through the app and web platform, users can monitor and receive notifications when environmental metrics exceed or fall below preset thresholds.
The AirSuite Glance can pinpoint hidden factors contributing to poor air quality and alert users to conditions they may have grown accustomed to. The wireless connectivity offers near real-time response capabilities, which is crucial as environmental factors can change rapidly. For instance, carbon dioxide levels can rise quickly in a crowded meeting room due to human respiration. Such alerts enable immediate intervention, which historical data analysis alone cannot achieve.
The next step in air quality monitoring is the introduction of a new generation of wireless SoCs, such as the Nordic nRF54H20, a multi-core, multi-protocol SoC with ample resources to support machine learning (ML). These SoCs can use long-term collected air quality data to train ML models, which can then be applied to the sensors. In turn, the sensors can assist in intelligently adjustments to building systems and HVAC to optimize occupant health and comfort.
This device optimization reduces power consumption by avoiding unnecessary usage while creating an indoor environment finely tuned for occupant well-being. Further integrating machine learning into wireless air quality monitoring is expected to provide enhanced predictive insights, enabling informed decision-making for better health outcomes. The result will be IoT solutions that deliver fresh air for everyone.
Accurate temperature and humidity measurements ensure optimal comfort for building residents
Another example is a solution developed by Adeunis, a leading French IoT sensor specialist, designed specifically for smart buildings to monitor indoor environment and air quality. The COMFORT and COMFORT Serenity devices use temperature, humidity, carbon dioxide (CO2), and VOC sensors to provide near real-time data to the cloud. They are powered by Nordic's nRF9160 SiP, supporting cellular IoT connectivity with NB-IoT and LTE-M networks.
With Adeunis sensors, building supervisors can access data regarding potential exposure to high concentrations of carbon dioxide or VOCs, which may pose health risks. Therefore, it is crucial to monitor and maintain safe levels. Additionally, Adeunis' devices ensure optimal comfort for building occupants through precise temperature and humidity measurements.
Nordic's nRF9160 SiP features a 64 MHz Arm Cortex-M33 dedicated application processor, providing sufficient processing power to manage the integrated sensor suite. Once device data is transmitted to the cloud via the nRF9160 SiP, users can review and manage information through an intuitive app with an NFC interface. The cloud server offers insights into sensor status, battery life, network quality, and data reception, allowing users to delegate device management, remotely configure devices, and take actions based on collected data.
The nRF9160 supports both LTE-M and NB-IoT technologies in a single SiP, offering unparalleled flexibility. Furthermore, its excellent low-power capabilities are a key factor, as extending battery life to the maximum is essential when using multiple sensors in each building. Adeunis' devices can achieve an impressive battery life of up to 15 years.
Highly integrated and innovative IoT solutions
The nRF54H20 System-on-Chip (SoC), introduced by Nordic, is the first SoC in the nRF54H series. It is a compact, ultra-low-power SoC with outstanding processing power, large memory capacity, and exceptional efficiency. Featuring a best-in-class new multi-protocol radio and state-of-the-art security features, this unique combination of functionalities integrated into a compact SoC will enable developers to create unprecedented innovative IoT products.
The nRF54H20 replaces multiple components with a highly integrated SoC, requiring minimal external components, reducing design size. Its efficient processing, ultra-low-power radio, and minimal sleep current extend battery life or allow for smaller battery sizes. It features best-in-class multi-protocol radio, with a transmission power of 10 dBm, reception sensitivity of -100 dBm for Bluetooth LE, and 802.15.4 reception sensitivity of -104 dBm, enabling long-range communication. The nRF54H20 includes state-of-the-art security features, such as secure boot, secure firmware updates, secure storage, and physical attack protection to defend against security threats.
Another product from Nordic, the nRF9160 low-power System-in-Package (SiP), integrates an LTE-M/NB-IoT modem and GNSS. This compact, highly integrated SiP brings the latest low-power LTE technology, advanced processing, and security accessible and easy to use, making it ideal for a variety of single-device low-power cellular IoT (cIoT) designs.
The nRF9160 features a built-in Arm Cortex-M33 application processor, full LTE modem, RF front-end (RFFE), and power management system. It is one of the most compact, complete, and energy-efficient cellular IoT solutions on the market. The integrated modem supports LTE-M and NB-IoT, capable of running globally without the need for regional variants. The nRF9160 supports all power-saving features, including eDRX and PSM, and supports IPv4/IPv6 transmission and security (TCP/TLS) levels. It can perform secure, encrypted firmware over-the-air (FOTA) updates to upgrade modem firmware.
Conclusion
According to statistical data, the global air quality monitoring system market is expected to reach $6.9 billion in revenue by 2028, indicating a promising market outlook. Wireless air quality monitoring devices can monitor indoor air quality changes at any time, and when combined with IoT solutions, they can provide fresh air for everyone, leading to better health outcomes. Nordic's highly integrated SoC and SiP solutions can accelerate product development for wireless air quality monitoring device manufacturers, making it worthwhile for you to explore and adopt further.