Fire prevention and control systems - Fire alarms - Electrical alarm circuits -Smoke extraction and ventilation -Gas extinguishers - Types of detectors - Gas installation and components.
2. FIRE SAFETY INSTALLATION
Fire prevention and control systems - Fire alarms - Electrical alarm
circuits -Smoke extraction and ventilation -Gas extinguishers - Types of
detectors - Gas installation and components.
3. FIRE PREVENTION AND CONTROL SYSTEMS
• Stipulation of the various fire protection measures for building, to
minimise the loss of life & property and effects of fire on surrounding
area, are broadly based on following aspects/ philosophy.
5. Extinguishing of fire
•Cooling – fire extinguishing by the application of water acts by removing heat from the
fuel faster than combustion generates it.
•Oxygen starving (பட்டினி) – application of carbon dioxides is intended primarily to
starve the fire of oxygen. Ex., putting fire blanket to cut off the oxygen
supply.
•Remove fuel source – a forest fire may be fought by starting smaller fires in advance of
the main blaze, to deprive it of fuel. Ex., physical removing fuel
•Interference of Chemical reaction – other gaseous fire suppression agents, such as halon
or HFC-225, interfere with the chemical reaction itself.
7. Rising Mians
(a) Dry riser (RED)
• Any floor is at a habitable height beyond 24 m and not exceeding 60 m above the ground level.
• For a building under purpose group of the fire code, having a habitable height exceeding 10 m but
not exceeding 60 m.
(b)Wet riser (Yellow)
• Any floor exceeding habitable height of 60 m above ground level
• Wet rising main zone heights exceeding 76 m may be permitted when a listed
pressure regulating device, which controls nozzle pressure under both flow and no flow
conditions is installed at each outlet in house rise buildings, the following requirements are
also applicable to wet risers:
• The maximum zone height shall not exceed 120 m
• The pressure regulating device is arranged to regulate pressure at the hose valve
outlet to a running pressure not exceeding 5.5 bar
• The pressure on the inlet side of the pressure regulating device does not exceed the
working pressure rating of the device
• All other pipe fitting and devices on the system are rated for not less than the
maximum system pressure.
10. Fire Safety precautions
• Don't overload outlets with multiple outlet cords or plugs. If
additional outlets are required, use an IS marked multi-outlet "power strip"
with its own built-in circuit breaker.
• Careless smoking, use of candles and incense, and unattended
cooking appliances remain major causes of fatal fires in residential
buildings. Use of fire crackers, hot work, and open fire is prohibited in all
buildings.
• Keep walkways, stairwells and exits free from obstructions at all
times.
• Report immediately if you observe/noticed damaged fire equipment
and other fire hazards to Campus security and Fire Safety wing.
• Do not open fire hydrant/hose reel water for unnecessarily use.
• Do not misuse of Fire Extinguisher.
12. Dry Pipe System
•Above the control valves, system is charged with compressed air/nitrogen instead of water
•Dry pipe valve held closed by air pressure
•Upon activation of sprinkler head, air is released and water flows into the pipe work
•For areas subjected to freezing temperatures.
13. Pre-Action System
• For areas where accidental discharge of water is unacceptable.
• Pipes filled with low pressure air.
• Heat/ smoke detector send signal to valve to release water to pipe work and sound alarm.
• When sprinkler burst, water is discharged.
• Prevent unwanted water flow when a pipe or sprinkler is accidently broken.
14. (d). Deluge System
• Pipes are usually empty, sprinkler are open
• Detectors activate control valve to allow water to flow
• Water is discharged simultaneously through all the open sprinklers in
the area.
•Thus, providing fast and total wetting of protected areas.
•For areas that required total coverage (extra high hazard area such as
aircraft hangers, power generating stations, and petrochemical facilities).
15. Fire protection equipment
Automatic fire detection system
Automatic sprinkler system
Automatic release mechanism
Automatic self-closing device
• Basement
Boundary
Cavity
Ceiling
Circulation space
.
•
16. Common Fire
Hazards
• Kitchen fire from unattended cooking, such as frying, boiling and simmering.
• Electrical systems that are overloaded, resulting in hot wiring or connections, or failed components.
• Combustible storage areas with insufficient protection.
• Combustibles near equipment that generates heat, flame, or sparks.
• Candles and other often flames
• Smoking (cigarettes, cigars, pipes, lighters, etc.).
• Equipment that generates heat and utilizes combustible materials.
• Flammable liquids and aerosols.
• Flammable solvent (and rags soaked with solvent) placed in enclosed trash cans.
• Fireplace chimneys not properly or regularly cleaned.
• Cooking appliances-stoves, ovens.
• Heating appliances-fireplaces, wood burning stoves, furnaces, boilers, portable heaters.
• Household appliances-clothes dryers, curling irons, hair dryers, refrigerators, freezers.
• Chimneys that concentrate creosote.
• Electrical wiring in poor condition.
• Leaking Batteries.
• Personal ignition sources-matches, lighters
• Electronic and electrical equipment
• Exterior cooking equipment-barbecue
17. FIRE ALARM
Fire alarm systems generally use visual and audio signalization to warn the
occupants of the building. Some fire alarm systems may also disable elevators,
which under most circumstances, are unsafe to use during a fire.
18. Fire Alarm Control Panels
(a) Function of control panel
• It is the brain of the fire detection and alarm system
• Responsible for monitoring the various alarm input devices such
as manual and automatic detection components
• Activates alarm output devices such as horns bells warning lights
emergency telephone diallers and building controls
(b) Design
• Control panels may range from simple units with a single input
and output zone, to complex computer driven systems that monitor
several buildings over an entire campus.
20. Conventional Systems
(a) Conventional
• Point wired – have a dedicated writing back to the signal processing
• One or more circuits are routed through the protected space of the building.
• Along each circuit, one or more detection devices are placed
(b) Factors for selection & placement
• Depends on need for automatic or manual initiation
• Ambient temperature & environment conditions
• Anticipated type of fire
• Desired speed of response
(c) Fire occurrence situation
• One or more detectors will operate
• Action will close the circuit which the fire control panel recognizes as an emergency condition
• Panel will then activate one or more signalling alarm circuits to sound building alarm and
summon emergency help
• Panel may also send the signal to another alarm panel so that it can be monitored from a
remote point.
21. (d) Fault monitoring
• To help ensure that the system is functioning properly
these systems monitor the condition of each circuit by sending a
small current through the wires.
• Should a fault occur, such as due to a wiring break this
current cannot proceed and is registered as a trouble condition
• The indication is a need for service somewhere along the
respective circuit
22. Addressable systems
(a) Addressable systems
• State of the art in fire detection and alarm technology
• Monitors and controls the capabilities of each alarm initiating and signalling device through
microprocessor and systems software
• Major differences involve the way in which each device is monitored
• Each initiating device (automatic detector, manual station, sprinkler water flow switches) is given a
specific identification or address
• This address is correspondingly programmed into the control panels memory with information such
as the type of device its location and specific response details such as which alarm devices are to be
activated.
(b) Operations
•The control panels microprocessors send a constant interrogation signal over each circuit
•Each initiating devices is contracted to inquires its status (normal or emergency)
•This activates monitoring process occurs in rapid succession providing system updates every 5 to 10
seconds
•Therefore, instead of merely showing a fault along a wire they will indicate the location of the
problem
•This permits faster diagnosis of the trouble and allows a quicker repair and return to normal.
24. Fire Alarm Control Panels
(a) Function of control panel
• Control panel is the brain of the fire detection and alarm system
• Responsible for monitoring the various alarm input devices such
as manual and automatic detection components
• Activates alarm output devices such as horns bells warning lights
emergency telephone diallers and building controls
(b) Design
• Control panels may range from simple units with a single input
and output zone, to complex computer driven systems that monitor
several buildings over an entire campus.
30. SMOKE EXTRACTOR AND FIRE VENTILATOR
• Number and area of ventilators - estimates are based on providing a smoke-
free layer about 3 m above floor level.
35. PORTABLE FIRE EXTINGUISHERS (ACID BASED)
• A portable fire extinguisher must contain the type of fire extinguishing agent suitable
for the fire it is required to extinguish. It must also be clearly identifiable by colour
coding for its intended purpose.
36. Portable fire Extinguishers
Extinguishing agent Extinguisher colour Application
Water Red
Carbonaceous fires,
paper, wood, etc.,
Foam Red with cream band
Ditto and flammable
liquids, oils, fats, etc.,
Carbon dioxide Red with black band
Electrical fires a
flammable liquid
Dry chemicals Red with blue band All fires