Skip to content
Stand with Ukraine flag

Humidity Out-of-Range Alarm

  • Alarm Rule
  • 0 installs
  • v1.0.0
  • Aug 11, 2026
  • MIT license
  • v4.3+

Monitor relative humidity and alarm when it drifts too dry or too damp, for greenhouses, cold storage, server rooms, museums, and building comfort.

Type
  • Alarm
Category
  • Threshold
  • Environmental
Use Cases
  • Environment Monitoring
  • Cold Chain
  • Smart Farming
  • Smart Building

Who it’s for

Facility managers, greenhouse and grow-room operators, and cold-storage or server-room technicians. Reach for it when relative humidity has to stay inside a comfort or preservation range and either edge deserves an alarm: “is the air too dry and cracking timber, paper, or electronics?”, “is a grow room or produce cooler drifting too damp and inviting mould?”, “is a museum or archive room holding its target humidity band?”

What it does

Reads the device’s humidity telemetry and raises a Major alarm when relative humidity goes too high or too low and stays out of range long enough. The alarm auto-clears once humidity returns to a tighter safe range and stays steady there.

Humidity Out-of-Range Alarm diagram

How to set up

The rule has default values for every threshold, so it works as soon as it is installed. Install on a device or asset profile so the alarm covers every entity of that type at once and automatically picks up any new entity added later. Single-device or single-asset installs are also supported.

How to customize

  • To monitor a different telemetry - change the Time series key on the metric argument (e.g. humidityrh or relativeHumidity to match your sensor’s key).

  • To use different threshold attribute names - change the Attribute key on the threshold arguments to match what your devices or assets already use (e.g. humidityWarningHighrhMax).

  • To change the trigger and clear thresholds used when no per-entity attribute is set - change the Default value on the warningHigh, warningLow, clearHigh, and clearLow arguments.

  • To change how long a reading must stay out of range before firing or clearing - change the Default value on the holdMinutes or clearHoldMinutes arguments.

  • To tune thresholds and hold durations at runtime without editing the rule - set the value on the entity as a regular server-side attribute. It can be edited directly from a dashboard using Update Multiple Attributes input widget:

    • Per device or asset - set the attribute (e.g. humidityWarningHigh, humidityHoldMinutes) on the device or asset itself. The per-entity value overrides the Default value.
    • Per customer (in deployments that use customers) - change Entity type on the relevant argument to Current owner, then set the attribute on the customer. Every device that customer owns picks up that value.
    • Tenant-wide - change Entity type to Current tenant, then set the attribute on the tenant. The value applies across every device.
  • To make the alarm manual-clear-only - remove the Clear condition. The alarm then stays active until an operator clears it.

  • To restrict firing to occupied hours - in the trigger condition’s Schedule, choose Active at a specific time range (or Custom schedule for different intervals per day). For per-entity schedules - e.g. different rooms with different hours - switch to Dynamic mode and source the schedule JSON from an attribute on the entity.

  • To control where the alarm shows up - toggle the propagation flags under Advanced settings.

Share Your Alarm Rule with the Community

Built a reliable alarm rule? Export it as a JSON from ThingsBoard and publish it to the IoT Hub. Share it with thousands of ThingsBoard developers and help the community react to incidents faster.