Fire Detection and Alarm System
What is an SDAI?
SDAI is the system responsible for detecting incipient fires, alerting occupants, and activating protection devices. Regulated by ABNT NBR 17240, it is mandatory in practically all commercial, industrial, and public-assembly buildings in Brazil.
Components of an SDAI
Fire alarm control panel
The brain of the system. Supervises loops, processes alarms, and commands output devices.
View Firebee product →Smoke detectors
Optical, ionic, or combined. Conventional, addressable, or wireless depending on the project.
Heat detectors
Rate-of-rise or fixed-temperature. For kitchens, garages, and areas with ambient smoke.
Manual call points
Alarm call points with break-glass or push activation, addressable or wireless.
Audible & visual alarms
Sirens and strobes for evacuation. Addressable, with zone and volume control.
Functional architecture
A typical SDAI operates in three layers:
- Detection — sensors (smoke, heat, flame) and manual call points collect signals from the environment.
- Processing — the central panel receives signals via addressable, wireless, or conventional loop; applies confirmation logic (double-knock, zone verification) and decides on actions.
- Notification/action — audible and visual alarms alert occupants; I/O modules command elevators, dampers, sprinklers, pressurized stairs, HVAC.
Applicable standards
ABNT NBR 17240
SDAI — Design, installation, commissioning, and maintenance. Applicable Brazilian standard.
ABNT NBR 9441
Execution of fire detection and alarm systems (superseded by 17240).
ISO 7240
Fire detection and alarm systems — international series (14 parts).
IT 19 CBPM
Technical Instruction for Fire Detection and Alarm Systems of the state fire brigades.
Stages of an SDAI project
Risk assessment and occupancy classification
Executive design per NBR 17240
Approval by the fire brigade
Installation and commissioning
Functional testing and ART
Periodic maintenance (monthly, semi-annual, annual)