Ozone (O3) card

Who it’s for

Environmental health officers, air quality managers, and smart city operators ask “is ozone at this monitoring point within safe limits right now?” They track ground-level O₃ on air quality dashboards because elevated ozone, formed from sunlight reacting with traffic and industrial emissions, peaks in afternoon hours and can trigger respiratory advisories.

What it does

A monitoring station reporting ozone = 65 µg/m³ displays the reading on a color-coded card: green for Good (0–50 µg/m³), light green for Moderate (50–100 µg/m³), orange for Elevated (100–130 µg/m³), dark orange for High (130–240 µg/m³), and red for Hazardous (above 240 µg/m³).

• Live O₃ reading in µg/m³ with automatic color coding across five severity bands
• Severity bands follow WHO and EU air quality guideline thresholds for ground-level ozone
• Shows one sensor’s reading per widget; add multiple widgets to monitor stations across a network

How to set up

Data keys

Key	Role	Type	Description
ozone	Main value	Timeseries	Ozone concentration in µg/m³; change the key name to match your device’s telemetry key

The widget ships with a simulated function datasource key labeled Ozone, 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	Level	Color
0–50	Good	Green
50–100	Moderate	Light Green
100–130	Elevated	Orange
130–240	High	Dark Orange
240+	Hazardous	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 for each severity level in the widget settings to match your organization’s color scheme.
• To rename the units label — change the Units field in the widget settings if your sensor reports in ppb.

Tips

• Ground-level ozone typically peaks in the afternoon when solar radiation is strongest; monitor this card from midday onwards on clear, hot days when photochemical conditions are most favorable.
• Ozone concentrations are often higher downwind of city centers than at the source — check rural monitoring stations as well as urban ones to identify elevated levels outside the city.
• For compliance reporting, pair this card with an O₃ chart card so inspectors see both the current reading and the daily trend without switching views.