Carbon monoxide (CO) chart card with background

Who it’s for

Environmental health officers, air quality managers, and smart city operators ask “what is the CO level right now and has it been rising — and can I see the severity status from across the room?” The background-color chart variant combines real-time trend visibility with high-contrast room-level status communication.

What it does

A monitoring station reporting carbon = 3.2 mg/m³ displays the current value and a historical trend chart on a card whose background fills with the severity color: green for Good (0–5 mg/m³), light green for Moderate (5–10 mg/m³), orange for Elevated (10–25 mg/m³), dark orange for High (25–50 mg/m³), and red for Hazardous (above 50 mg/m³).

• Full-card background color communicates severity at a glance from a distance
• Historical trend chart shows how CO concentration has evolved over the selected time window
• Shows one sensor’s data per widget; add multiple widgets to track stations across a network

How to set up

Data keys

Key	Role	Type	Description
carbon	Chart series	Timeseries	Carbon monoxide concentration in mg/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 Carbon monoxide, 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
0–5	Good	Green
5–10	Moderate	Light Green
10–25	Elevated	Orange
25–50	High	Dark Orange
50+	Hazardous	Red

How to customize

• 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 background color for each severity level in the widget settings.
• To change the time window — adjust the dashboard time filter to show the last hour, day, or week of CO readings.

Tips

• On a wall display, the colored background signals the current severity from a distance while the embedded chart gives analysts the context they need when they approach the screen.
• Use consistent severity colors across all air quality widgets on the same dashboard.
• A sudden spike that returns to baseline within minutes typically indicates a transient source; a sustained rise over hours points to a persistent emission source worth investigating.