Ozone (O3) chart card

Who it’s for

Environmental health officers, air quality managers, and smart city operators ask “what is the ozone level right now, and is it rising toward the afternoon peak?” They need both the current reading and the intraday trend to issue public advisories before ozone reaches harmful levels.

What it does

A monitoring station reporting ozone = 65 µg/m³ shows the current value color-coded by severity alongside a time-series chart of recent readings: 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). The chart shows whether the reading is still climbing or has already peaked.

• Live O₃ reading in µg/m³ with color coding across five severity bands
• Historical trend chart shows how ozone concentration has evolved over the selected time window
• Shows one sensor’s data per widget; add multiple widgets to track and compare stations across a network

How to set up

Data keys

Key	Role	Type	Description
ozone	Chart series	Timeseries	Ozone concentration in µg/m³; change the key name to match your device’s telemetry key
Latest	Latest value	Timeseries	The headline figure above the chart. Its own color ranges are where the band colors are edited
Delta percent	Percentage change	Timeseries	Change against the previous period, as a percentage
Delta absolute	Absolute change	Timeseries	Change against the previous period, in the key’s own unit

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 time window — adjust the dashboard time filter to show the last hour, day, or week of O₃ readings.
• To change the severity thresholds — edit the color ranges on the Latest data key to match your local regulatory limits.
• To change the band colors — edit the color for each severity level in the widget settings.

Tips

• Ground-level ozone peaks in the afternoon; set the time window to 24 hours so the characteristic rise-and-fall diurnal cycle is visible, making anomalous high-persistence events stand out clearly.
• A reading that stays elevated into the evening rather than declining after sunset typically indicates an unusual meteorological event such as a temperature inversion trapping pollutants near the surface.
• For compliance reporting, use the chart’s export feature to download the raw time-series data for the period under review.