6. Disaster Prevention & Protection Systems

Active Fire Protection

• AFP is a fire protection system using manual or automatic actions that work during a fire
• Examples include:
  • Fire/Smoke alarm systems
  • Sprinkler systems
  • Fire extinguishers
  • Firefighters
• Fire/Smoke alarms detect fire and or smoke
• Sprinkler systems slow the growth of the fire
• Fire extinguishers and firefighters work to put out the fire

Manual Fire Suppression Systems

• Fire Blanket:
  • A fire-extinguishing equipment for extinguishing small fires
  • Made of wool or fiberglass fabric treated with fire retardant chemicals
• Fire Extinguisher:
  • A portable device for putting out small fires
  • Ejects pressurized water or chemicals
  • Fire Extinguisher Classes:
    • Class A: ordinary combustible materials (e.g., wood, paper, cloth)
    • Class B: flammable liquids (e.g., gasoline, oil, grease)
    • Class C: electrical equipment
• Standpipe:
  • A building's vertical water piping system for manual water application
  • Dry Standpipes: Used in buildings with four or more stories, located near stairwells, providing 900 liters of water per minute from three outlets
  • Wet Standpipes: Used in buildings with more than 1000 occupants, extending from the basement to the topmost floor

Automatic Fire Suppression Systems

• Fire Sprinkler System:
  • An active fire protection system using water supply for fire sprinkler activation
  • Sprinkler System Types:
    • Wet: Piping filled with water under pressure; sprinklers activate upon fire detection.
    • Dry: Piping filled with pressurized air; valves and sensors trigger water release upon fire detection.
    • **Pre-action:**Similar to dry systems but with added safety features; water release occurs via an electronic valve after fire detection.
    • Deluge: All sprinklers open with activation; water release occurs without heat sensing elements.
• Sprinkler Head Coverage:
  • Light Hazard Occupancy: 20 square meters
  • High Hazard Occupancy: 10 square meters
• Sprinkler Head Types:
  • Pendant:
    • Hangs from ceiling pipes, spraying water in a domed or conical pattern
    • Traditional pendant sprinklers are visible
  • Upright:
    • Project upwards, spraying water downwards
    • Used in mechanical rooms or inaccessible spaces, providing better coverage.
  • Sidewall:
    • Mounted on walls, spraying in a crescent or half-circle shape.
    • Effective in small rooms and hallways.
    • Common application for hotel rooms.
  • Concealed:
    • Installed in walls or ceilings, covered by a concealed plate
    • Heat-sensitive plate detaches when activated, releasing water.

Passive Fire Protection (PFP)

• Aims to contain fires or slow their spread
• Building Construction and Materials:
  • Fire Walls: Designed to stop fire spread.
  • Fire Blocks: Contain fire spread.
  • Smoke Barriers: Prevent smoke spread.
• Fire Compartmentation: Building design using walls and floors to create fire compartments, controlling fire spread and protecting occupants by creating safe evacuation routes.

Fire Alarm and Detection System

• Automatic System: Uses detectors to trigger the alarm system.
• Manual System: Requires human detection to trigger the alarm.

Automatic Fire Alarm System:

• Uses sensors to detect fire, sending signals to the fire alarm panel
• 3. Addressable Fire Control Panel (FACP):
  • Identifies the exact fire location within a building.
  • Allows shutdown of equipment to prevent further damage or injury.
  • Detects potential fire conditions.
  • Provides information about the fire's circumstances.
  • More reliable than other panels, enabling quicker action.
• A. Fire Alarm Control Panel (FACP):
  • The fire alarm system's central control unit.
  • Monitors initiating devices and relays signals to fire alarm devices.
  • Displays system status and troubleshooting codes.
  • Includes a touch panel for system management.
• B. Primary and Backup Power Supply:
  • Primary power constantly supplies the system.
  • Backup power (using batteries) ensures system function during power failures.
• C. Alarm Initiating Device:
• Informs the fire alarm system of fire emergencies.
• Can be manual or automatic (using heat, smoke, flame, photoelectric, ionization, in-duct detectors).
• Most commercial systems use a combination of manual and automatic devices.
• 1. Coded Panels:
  • Older systems, indicating fire by the number of bells or horns ringing.
  • Require manual reset by an employee.
  • Used in older buildings.
• 2. Conventional Panels:
  • Operate on circuits with sensors wired in parallel.
  • Limited by the number of circuits.
  • Used for zone-based boundaries in commercial buildings.

Detection System

• 1. Temperature Detector
  • Fixed Temperature Unit: Triggers when a set temperature is reached.
  • Rate-of-rise Unit: Activates when the temperature change exceeds a predetermined rate.
• 2. Photoelectric Detector:
  • Detects smoke obscuring a light beam.
• 3. Ionization (Smoke) Detector:
  • Detects ionized particles in the air.
• 4. Flame Detectors:
  • a. Infrared: Used for enclosed spaces.
  • b. Ultraviolet: More sensitive than infrared, used in flammable areas.

Alarm Notification Device (D)

• Activated by initiating devices (e.g., smoke detectors).
• Produces audible alarms to alert occupants during a fire emergency.
• Notifies emergency personnel.

Remote Control and Display Panels (E)

• Allow centralized control of fire alarm systems, even remotely.
• Enable security personnel to check, activate, and deactivate alarms throughout the building.

Building Safety Interface (F)

• Connects the fire alarm system with other building systems (e.g., access control).
• Improves building safety during a fire emergency by controlling door access and smoke spread.

Detection Methods (Diagram: "Through Beam")

• A “Through Beam” system utilizes a transmitter and receiver.
• Detects obstructions within the beam path.
• Triggers an alarm when an object blocks the beam path.

Warning Systems

• Bells, chimes, horns, strobes, horn-strobes, and voice evacuation systems provide warnings.

Auxiliary Devices

• 1. Dampers:
  • Passive fire protection products.
  • Used in HVAC ducts to prevent fire spread.
• 2. Heat and Smoke Vents:
  • Active fire protection measures.
  • Installed on building roofs to vent heat and smoke.

Earthquake Mitigation

• 1. Pendulum Power:
  • Suspended large mass near the top of a structure.
  • Counteracts seismic energy by moving opposite to the structure's motion.
  • "Tuned mass dampers" are tuned to the structure’s natural frequency to reduce the dynamic response.
• 2. Symmetry, Diaphragms, and Cross-Bracing:
  • Symmetrical structures are preferred for seismic design.
  • Symmetrical structures distribute forces evenly and limit torsion caused by seismic activity.
• 3. Shock Absorption:
  • Similar to vehicle shock absorbers to reduce vibratory motions during earthquakes.
  • Shock absorbers are placed at each building level, connected to the beam and column.

Building Utilities

• 4. Rocking Core-Wall:
  • A cost-effective technique used in modern high-rise buildings to increase their seismic resistance.
  • In this method, a reinforced concrete core is placed in the center of the building, surrounded by elevators.
  • Works most effectively when used with base isolation.
• 5. Floating Foundation: “Base Isolation”
  • This technique separates the substructure from the superstructure of a building by using lead-rubber bearings.
  • During an earthquake, the floating foundation can move without moving the entire structure.
• 6. Carbon-fiber Wrap
  • Used to improve an existing building’s seismic performance.
  • Carbon fibers are wrapped around a building to strengthen it.