Volatile organic compounds chart card with background
Who it’s for
Indoor air quality managers, building managers, and health and safety officers ask “how has VOC concentration trended in this space recently?” The chart with background combines compact trend visualization with a full-card color signal so the current status is visible at a distance.
What it does
A sensor reporting voc = 320 ppb renders a time-series trend chart on a card whose background color reflects the current severity: green for Good (0–500 ppb), orange for Moderate (500–1000 ppb), and red for Hazardous (above 1000 ppb).
- Full-card background color communicates current severity at a glance from a distance
- Trend chart of VOC concentration over the selected dashboard time window
- Shows one sensor’s data per widget; add multiple widgets to compare trends and current status across rooms
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
voc | Chart series | Timeseries | VOC concentration in ppb; 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 VOCs, 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 |
|---|---|---|
| 0–500 | Good | Green |
| 500–1000 | Moderate | Orange |
| 1000+ | Hazardous | Red |
How to customize
- To change the time window — adjust the dashboard time filter to show the last hour, day, or week of VOC readings.
- To change the severity thresholds — edit the color ranges on the Latest data key to match your organization’s indoor air quality policy.
- To change the background colors — edit the color of each range on the Latest data key.
Tips
- On a wall display, the colored background signals the current VOC severity from across the room while the embedded chart shows whether post-renovation off-gassing is still elevated or already clearing.
- Use consistent severity colors across all indoor air quality widgets so facilities staff can interpret a red background anywhere on the dashboard without reading the label.
- VOC levels that remain in the Moderate band for several consecutive days after a renovation indicate the materials are still actively off-gassing and the space should not be fully reoccupied until the chart returns to the Good band.
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