Why it matters
The people in immediate danger are the ones standing next to the device, and they need to be told first and unconditionally. An alarm that requires a round trip to a server inherits every failure of that server as a safety failure.
Monitoring & detection
Local alarm
A local alarm is an audible or visual warning produced by the sensing device itself, without depending on a network, server or remote service.
How it works
Threshold evaluation runs on the device, and the device drives its own buzzer, display or beacon directly from that evaluation - before, and independently of, any attempt to transmit.
Example
A gas leak in a workshop with no internet connectivity still sounds the buzzer on the node.
In Alfa HazardX
The buzzer, display and LED matrix are driven by on-device evaluation. Publishing to the cloud is deliberately the last step in the control loop.
Read further
Related terms
- Fail-safeA fail-safe design ensures that when a component fails, the system moves to a safe state rather than an unsafe or unknown one.
- Hazard detectionHazard detection is the act of determining that a hazardous condition exists now, usually by comparing a sensor reading against a defined limit.
- Edge intelligenceEdge intelligence is processing and decision-making performed on the device that collects the data, rather than on a remote server.