Implementing Fire Alarm Monitoring via Mobile Applications
Fire alarm monitoring is a domain where the cost of a software error is incomparably higher than in regular IoT. The panel receiver-controller ("Bolid S2000-KDL", Honeywell NOTIFIER, Siemens Sinteso) always remains primary: mobile app reads its state but never replaces local automation. No "Reset Alarm" button in the phone should work without confirmation on the physical panel.
Integration with Panel via OPC DA/UA and RS-232
Old panels (S2000-KDL, Bolid) use RS-232 with proprietary protocol — documentation by request from manufacturer. Modern systems provide OPC UA server or MODBUS TCP. For Honeywell NOTIFIER — REST API via LifeSafety Power Manager.
Typical scheme: gateway on Linux mini-server in server room reads panel via RS-232/OPC and publishes normalized events to MQTT. Mobile client subscribes to MQTT over TLS.
Topic structure:
fire/{buildingId}/panel/{panelId}/zone/{zoneId}/state
fire/{buildingId}/panel/{panelId}/alarm
fire/{buildingId}/panel/{panelId}/fault
Zone state — enumeration: normal, alarm, fault, disabled, test.
Priorities and Display
In app, events are ranked strictly by priority:
enum FireEventPriority { alarm, fault, warning, normal }
Color getZoneColor(ZoneState state) => switch (state) {
ZoneState.alarm => const Color(0xFFD32F2F), // red
ZoneState.fault => const Color(0xFFFF6F00), // orange
ZoneState.disabled => const Color(0xFF757575), // grey
ZoneState.test => const Color(0xFF1976D2), // blue
ZoneState.normal => const Color(0xFF388E3C), // green
};
Alarm must be immediately visible: FCM priority: high + notification.android.channel_id with IMPORTANCE_HIGH and sound. Without notification_priority: PRIORITY_MAX on some Xiaomi/Huawei, notification gets lost in background.
Event Log and Responsible Officer
Every alarm event is logged with timestamp, zone ID, sensor type, and user who acknowledged receipt. "Acknowledgement" in app is only additional information layer, not replacement for physical reset on panel.
Developing fire alarm monitoring app with zone map, live state and alarm push notifications: 3–5 weeks. Cost calculated individually after analyzing panel type and integration requirements.