Simple ozone (O3) chart card

Who it’s for

Environmental health officers, air quality managers, and smart city operators ask “how has ozone concentration at this station trended over the last few hours or days?” They want a compact trend chart that fits into a multi-station overview without the overhead of a full chart card.

What it does

A monitoring station streams ozone telemetry and the widget renders a time-series chart of those readings, color-coded by severity: 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 fills the card without a large numerical readout, maximizing the visible time window.

• Trend chart of ozone concentration over the selected dashboard time window
• Color-coded by severity at each point in time across five bands
• Shows one sensor’s data per widget; add multiple widgets to compare trends across stations

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

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 change the chart colors — edit the color of each range on the Latest data key.

Tips

• Use this chart in a grid alongside simple chart cards for CO, NO₂, and SO₂ to give operators a side-by-side multi-pollutant trend view without cluttering the dashboard with large value cards.
• The diurnal ozone cycle — low at dawn, rising through the morning, peaking in the afternoon, and declining at night — is a normal pattern; a 24-hour time window makes deviations from this baseline immediately obvious.
• Ozone levels that remain high overnight often indicate regional transport of polluted air masses rather than local photochemical production, which requires a different regulatory response.