The uRADMonitor MODEL A3 is a plug-and-play, automated air quality monitoring station designed for continuous, unattended operation. Using 8 high-quality sensors, it simultaneously tracks 11 environmental parameters: particulate matter (PM1, PM2.5, PM10), ozone, formaldehyde, carbon dioxide, volatile organic compounds (VOC), temperature, barometric pressure, humidity, and noise level. It is lab-tested for accuracy , validated by INCD Ecoind Romania, AQMD in the USA, and AIRLAB AIRPARIF in France multiple times.

The A3 is available in four connectivity variants: Ethernet, WiFi, GSM, and LoRaWAN making it easy to deply at home, in a smart city deployment, in a university research network, or an industrial monitoring application. It runs on under 1 Watt, accepts 6–28V DC input, and transmits data automatically to the uRADMonitor cloud or your local network via API. Compact in size and deployed across 60+ countries, the MODEL A3 is one of the most capable and field-proven multi-parameter air quality sensors in its class.

Stevenson Shield v15, what’s new?

The Stevenson Shield is the outdoor enclosure for the MODEL A3. Made from UV-resistant ASA plastic with Stevenson-style radiation shield vents, it protects the electronics from rain, snow, and direct sun while allowing free passive airflow across the sensors, critical for accurate temperature, humidity, and gas readings. Version 15 introduces three meaningful hardware improvements.

Stainless Steel Rods for Extreme Mounting Rigidity

The most significant change in v15 is the addition of two stainless steel rods integrated vertically into the rear of the enclosure, passing through the mounting ears. When a metal band or hose clamp is threaded through the ears for pole or wall mounting, it runs behind the rods , sandwiched between the rods and the enclosure body. This geometry makes it mechanically impossible for the clamp to slip or rotate under load. The result is a mounting system that handles vibration, wind stress, and long-term outdoor exposure without loosening.

Structural Reinforcement of the 3D-Printed Body

The same stainless rods serve a second structural role: they clamp the 3D-printed layers together along the Z-axis , the axis most vulnerable in FDM-printed parts, where inter-layer adhesion is the limiting factor for tensile strength. By compressing the stack mechanically, the rods convert what would otherwise be a laminar structure into a cohesive, rigid assembly. The enclosure becomes substantially more resistant to impact and long-term stress compared to previous versions.

Antenna Port for Radio Variants

v15 adds a side protrusion designed for MODEL A3 variants with an external antenna (WiFi, GSM, LoRaWAN). The protrusion ships closed and is opened with a drill only when installing a radio-equipped board units going into the LAN variant remain unmodified. This keeps full IP65 integrity for all configurations while eliminating the need for a separate enclosure SKU per connectivity variant.

Compatibility

The Stevenson Shield v15 is compatible with all hardware versions of the uRADMonitor MODEL A3. It can be ordered together with the A3 (installed at the factory) or purchased separately and fitted in the field by removing 4 screws. Mounting straps up to 12mm wide pass through the 54mm clearance between the ears; both plastic zip ties and metal collars work. The power cable enters from the bottom, maintaining a drip loop that prevents water ingress.

The Stevenson Shield v15 for MODEL A3 is available on our shop.