Radon level card

Who it’s for

Building managers, property owners, and occupational health officers ask “is radon accumulating in this building above the action level?” They monitor radon continuously to fulfill occupational health obligations and protect occupants from long-term exposure to this naturally occurring radioactive gas.

What it does

A sensor reporting radon = 45 Bq/m³ displays the reading on a color-coded card: green for Safe (0–100 Bq/m³), orange for Elevated (100–200 Bq/m³), and red for High (above 200 Bq/m³).

• Live radon reading in Bq/m³ with automatic color coding across three severity bands
• Severity bands align with EU and WHO reference levels for indoor radon in occupied buildings
• Shows one sensor’s reading per widget; add multiple widgets to monitor different floors or zones

How to set up

Data keys

Key	Role	Type	Description
radon	Main value	Timeseries	Radon concentration in Bq/m³; change the key name to match your device’s telemetry key

The widget ships with a simulated function datasource key labeled Radon level, so it draws random values until you point the datasource at a device and rename the key.

To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.

Value ranges

Range (Bq/m³)	Level	Color
0–100	Safe	Green
100–200	Elevated	Orange
200+	High	Red

How to customize

• To change the severity thresholds — edit Icon color ranges and Value color ranges; set the same boundaries in both so the icon and the number always agree.
• To change the band colors — edit the color of each range in Icon color ranges and Value color ranges.
• To rename the units label — change the Units field in the widget settings if your sensor reports in pCi/L instead of Bq/m³.

Tips

• Radon concentrations are highest in basements and ground-floor rooms with poor ventilation; install sensors at floor level in these spaces for the most representative readings.
• Readings vary with ventilation, temperature, and atmospheric pressure — a sudden spike after a building is sealed overnight is normal, while sustained high readings over days indicate a structural issue that needs remediation.
• For occupational health compliance, archive daily average readings alongside sensor location metadata so inspectors can confirm measurements were taken in occupied zones at the correct height.