Fire Alarm and Evacuation Control System for Hospital Building
Our organization has developed an evacuation control system project for a hospital.
EVACUATION CONTROL SYSTEM DESIGN
Purpose of the Evacuation System
The alarm and evacuation control system is designed to broadcast emergency voice messages and light-sound signals to all building areas upon receiving a fire signal from the hospital's fire alarm system.
System Description
The facility is part of a building complex. The building includes a basement level. The functional purpose of the premises is a hospital. The basement and first floor house equipment blocks. Key solutions adopted in the project. Working documentation describes execution of the following work types:
- Wall-mounted speakers, door communication stations, digital output module, power amplifier, universal interface module, master communication station, 24V uninterruptible power supply, 220V uninterruptible power supply
- Cable laying and device connection
- System equipment configuration
The facility is equipped with fire alarm and evacuation control systems:
- Central equipment is provided for future connection of tenant notification lines in first-floor office spaces
- Existing evacuation system in management company offices
Key system parameters:
- System type 4, according to safety codes
- Number of notification zones: 5
- Number of door communication stations: 4
- Total acoustic power: 15W
Facility notification zones and their acoustic power:
- Zone 1 - 3W
- Zone 2 - 3W
- Zone 3 - 3W
Acoustics
The project provides 100% acoustic power reserve for each zone for future expansion without needing control equipment upgrades. Control equipment integrates into unified system via Ethernet network. Fiber optic communication lines are laid between hospital buildings according to the project.
The microphone console enables manual transmission of non-scheduled voice messages to notification zones or other buildings. The master communication station enables two-way voice communication with any door station or other building.
Local system control with zone division is activated automatically from fire alarm relays. Install door communication stations according to working drawings. Install central equipment in the control room:
- Digital microphone console
- Master communication station
Install control equipment in the designated cabinet in the server room according to specified layout and perform inter-unit connections. Connect control equipment to Ethernet network. Connect microphone console, master station and door communication stations to building control equipment.
Electrical Cable Connections
Use following cable types during installation:
- Fire-resistant cable for cable lines
- Fire-resistant cable for master station and door communication stations
- Shielded cable for microphone console connection
Route cables in the building:
- In PVC corrugated conduit above false ceiling
- In PVC corrugated conduit concealed in chases and behind partitions
- Exit light indicators and direction signs are provided in the project
System Power Supply
Equipment power is supplied from 220V 50Hz first category reliability network. Backup 24V power is provided by uninterruptible power supply with battery backup. Speaker power in facility premises is supplied through notification system loops. Backup 220V power for communication equipment is provided by 1000VA uninterruptible power supply.
Master station and door communication stations are powered through network equipment. Backup power sources ensure uninterrupted autonomous system operation throughout evacuation time. Maximum power consumption doesn't exceed 4.5kW. Protective grounding is performed according to electrical codes and manufacturer documentation.
Working Documentation for Production Building Fire Protection
All metal parts of electrical equipment must be grounded. Protective grounding resistance must not exceed 4 Ohms.
Power supply category: first category with one input and secondary circuit with backup.
Current type: AC input, DC secondary circuit.
Voltage: main input 220V, secondary circuit 24V
Installed power: 220W.
Protected Premises List and Characteristics
Evacuation control system equipment is installed in assembly workshop premises. Building structure features reinforced concrete columns and brick walls.
Main Technical Solutions Adopted in the Project
General information about system purpose:
The evacuation control system is designed to ensure people safety through timely notification of staff and visitors about fire and managing evacuation.
The system activates automatically from command signal generated by automatic fire alarm or extinguishing system.
Remote, manual and local activation is permitted according to safety regulations. Manual activation devices must meet requirements for manual call points.
The system includes technical means complex consisting of:
- sound speakers,
- light indicators,
- photoluminescent signs,
- manual activation devices,
- control equipment and cable lines installed in system cabinet.
Type 2 notification system is provided for protected premises:
- Notification methods:
- sound (siren, tone signal);
- light.
Sound level must be at least 75dB at 3m distance from speaker. Wall-mounted sound devices are installed with top part at least 2.3m from floor level. Number, placement and power of sound devices must ensure sound level in all areas of people presence.
Exit signs should be installed above evacuation exits. Evacuation direction signs should be installed at minimum 2m height. Manual call points are placed on evacuation routes for system activation by staff.
Manual call points are installed on walls and columns at 1.5m height with illumination at least 50lux. Control equipment is installed on non-combustible material walls at 0.8-1.5m height from floor level.
System Sound Pressure Calculation
Sound devices are installed in premises at minimum 2.3m height from floor level. Devices used in the system don't have volume controls and connect without connectors. Additional visual indicators may be installed in convenient locations. Sound signals must provide level at least 15dB above permanent noise level in protected area.
Actual sound level at arbitrary distance from speaker is determined by formula considering distance attenuation. Based on equipment characteristics and assuming workshop noise level, required notification sound level should be 80-90dB.
When using multiple speakers in one room, simultaneous operation increases sound level by 3dB. Considering sound pressure attenuation with distance and through doors, maximum distance between speakers should be 35m in premises. Equipment selection is determined by system type and equipment characteristics. System diagrams are presented in drawings.
System Power Supply
For uninterrupted power supply, speakers, manual call points and control equipment connect to network through backup power units with batteries. Network and connection lines are executed with shielded communication cable and copper conductor wire with appropriate cross-section.
System Autonomous Operation Time Calculation
According to reliability requirements, fire alarm and evacuation systems belong to first category electrical installations. With single power source, battery backup or UPS should provide power for 24 hours in standby mode plus 1 hour in alarm mode.
The system must remain operational during entire evacuation time.
Battery capacity calculation formula considers standby and alarm mode consumption with safety factor.
Battery capacity is sufficient for system operation for at least 24 hours in standby mode plus at least 1 hour in fire mode.
System power is supplied from distribution board. Device connection is performed with fire-resistant cables.
According to reliability requirements, fire alarm and evacuation systems are first category consumers. System power is supplied from 220V network.
Cable laying is performed in PVC conduit. All 220V electrical equipment is grounded for safe operation.
Grounding is performed with copper wire connected to existing grounding network. Grounding wire cross-section is selected to ensure resistance not exceeding 4 Ohms.
Qualified maintenance personnel requirements:
Maintenance and repair work is performed by qualified electricians. Personnel selection and qualification requirements follow established standards.
Only personnel instructed in safety rules and familiar with equipment manuals are permitted for system installation and maintenance.
Installation work should begin only after safety measures implementation. Work with electrical equipment must be performed with power disconnected.
During project implementation and subsequent operation, no harmful waste is generated. Designed systems don't emit harmful electromagnetic waves. All equipment used has valid certificates.