Sonoff Announces AirGuard CO2 Air Quality Monitor W/ Matter
SONOFF has released the AirGuard CO2 (SAWF-08P), an indoor air quality monitor that measures carbon dioxide levels alongside temperature and humidity, while supporting Matter over Wi-Fi for integration with smart home platforms including, of course, Apple Home.
Whilst many environmental sensors that rely on Zigbee or Thread networks, the AirGuard connects directly to the local network via 2.4GHz Wi-Fi, using Matter as the interoperability layer. This means the device can be paired directly with Matter controllers such as Apple TV4K or a HomePod hub without a Thread Border Router inside.
At the core of the AirGuard is a NDIR CO2 sensor, a technology commonly used in dedicated air quality monitors because of its accuracy and stability over time. The sensor measures CO2 concentrations between 400 and 5000ppm, with an accuracy rating of ±(50ppm + 5 percent).
In addition to CO2 levels, the device also tracks temperature and relative humidity. Things like PM2.5 and VOCs are not supported however. All three readings are shown on the built-in LCD display and can also be exposed to smart home platforms through Matter. Measurements update every five seconds, allowing the device to respond quickly to changes in occupancy or ventilation.
The AirGuard includes several built-in notification methods designed to alert users when air quality declines.
These include:
- coloured LED indicators for air quality status
- an audible alarm
- push notifications through the companion app
Users can configure alert thresholds and silence notifications if required, although this will be through the company’s own app.
The device can also store historical air quality data for up to 365 days, which can help identify patterns such as overnight CO2 build-up in bedrooms or humidity changes during seasonal weather shifts.
Because the AirGuard uses Matter over Wi-Fi, it can be added to Apple Home through a Matter pairing code. Once paired, its environmental readings can be used in automations alongside other accessories.
For example, users could create automations such as:
- activating a ventilation system or alter you to open a window when CO2 levels rise
- turning on a fan when humidity or temperature thresholds are reached
- sending alerts when overall indoor air quality drops
The device itself is purely a sensor, so it does not control appliances directly, but it can act as a trigger for other smart devices in the home.
Key specs include:
- Model: SAWF-08P
- Connectivity: Matter over Wi-Fi (2.4GHz)
- Sensors: CO2, temperature, humidity
- CO2 sensing: NDIR sensor
- Display: integrated LCD screen
- Power: USB-C, 5V 1A
- Dimensions: 70 × 103 × 26 mm
- Weight: 101g
The device runs on an ESP32-based microcontroller and requires continuous power through USB-C, meaning it is intended for desk or shelf placement rather than battery operation.
Air quality sensors have become increasingly common in smart homes, particularly as awareness grows around indoor CO2 levels in bedrooms, offices and classrooms. The AirGuard’s approach of using Matter over Wi-Fi, whilst not to some users’ preferences, means it can be added without another hub or dedicated radio network.
For Apple Home users, this is useful because it allows environmental monitoring to integrate directly into existing Matter setups, without relying on Zigbee hubs or cloud integrations. While the AirGuard focuses on CO2 rather than particulate matter or VOC detection, it still covers the environmental metric most closely associated with ventilation and occupant comfort.
You can purchase the Sonoff AirGuard for US$49.90 plus shipping directly from Sonoff’s online store.
