Fire Detection & Suppression

fire

heat/light energy that is released during a chemical reaction

fire wall

walls that divide a single building into two or more "buildings", if either side collapses the wall will not for the duration of its rating

fire barriers

make up rated assemblies/enclosures (e.g.: shafts, exit enclosures, exit passageways, horizontal exits, atriums, mixed use occupancy separation)

shaft enclosures

openings through ?oors/ceilings connecting adjacent ?oors. 1 hour rated when connecting less than 4 stories, or 2 hour if passing through a 2 hour ?oor assembly or if connecting 4 or more stories

fire partitions

demising walls separating tenants, residential units, corridor walls

smoke

collection of airborne solid and liquid particles and gasses emitted when a material combusts

smoke barrier

used as required to prevent the movement of smoke, have a 1 hour ?re resistance rating

smoke partition

like a smoke barrier, but does not have to resist ?re

incombustible

consisting of or made of material that will not burn if exposed to ?re

horizontal assemblies

?re resistance rating (1 or 2 hours) applied to ?oor and roof construction

means of egress

ability to exit a structure in an emergency

area of refuge

location in a building where ?re and smoke are excluded, and used to contain occupants during a ?re or emergency or until safe to evacuate. Has a steady supply of outside air, passive ?re protection, electrical integrity/emergency lighting, two way commun

fire resistance

values for how long a separation can resist the passage of ?re. Stated in terms of hours and can be increased with the use of sprinklers. (eg: walls, doors, windows, ?oors, etc.)

flame spread rating

measures the amount of ?ame and smoke a material generates. (e.g. Carpet, fabrics, etc)

incipient

invisible particulate matter like combustion gas is given off but no ?ame is visible, nor any smoke/heat generated. Sensors detect gas

smoldering

large particles become visible as smoke, but no visible ?ame or appreciable heat. Sensors are photoelectric

flame

appreciable heat is not immediate present, but follows very quickly. Sensors detect ?ame

heat

uncontrolled heat and rapidly expanding air is present and ?ames and smoke become major hazards. Smoke inhalation ultimately causes most injuries. Sensors detect heat.

compartmentation

� Critical, as it separates a building into sections
� Goal is to contain a ?re and limit its spread so people can escape and to protect other parts of the building that weren't originally subject to ?re
� Can serve as an area of refuge for occupants

smoke control

� The most important part of ?re protection because smoke moves so rapidly.
� Tricky to control because it can move in ways that ?re can't, and well beyond the location of ?re too
� Moves by natural convention forces between cool and warm air
� Goal is to

containment

same as compartmentation used to contain ?res is used here
� Eg: ?re dampers, gaskets on ?re doors, and automatic closing doors

passive smoke control system

a system of some barriers arranged to limit the
migration of smoke

active smoke control system

an engineered system that uses mechanical fans to
produce pressure differentials across smoke barriers or to establish air?ows to limit and direct smoke movement

smokeproof enclosure

a required exit which consist of a vestibule and continuous stairway enclosed from the highest point to the lowest point by 2-Hour walls and which exist into a public way or exit passage leading to one

stairways

pressurized to prevent smoke from entering them

vestibules

pressured slightly higher than the ?re ?oor, but less than the stairway

exit access

the portion of a means of egress system that leads from any occupied portion of the building to an exit

exit

the portion of a means of egress system that is separated from other occupied spaces by ?re-rated construction, and extends between the exist access and the exist discharge. Horizontal exist are ok.

exit discharge

the portion of a means of egress system between the exit and a public right of way

horizontal exits

a path of egress travel from one part of a building to another part of a building on the same level, which affords safety from ?re and smoke

exit passageway

similar to an exit, but horizontal, and leads to the exit discharge

area of refuge

required for each 200 occupants and must be 30" x 48" in an area protected from ?re and smoke

fire door

a fire resistive door assembly consisting of frame, door and hardware which provides a specific fire resistive rating when closed

fire assembly

a complete fire resistive assembly consisting of a fire door, fire damper, or fire window and its mounting farm and hardware. The entire thing must
be approved and labeled by a testing agency

fire containment

achieved through building materials, compartmentation and smoke control

fire suppression

achieved through sprinkler systems, standpipes, and other methods

standpipes

pipes that run the height of the building and provide water at each ?oor for ?re?ghting hose connection

fire sprinkler

the part of a ?re sprinkler system that discharges water when the effects of ?re have been detected

flashover

when materials become extremely hot and combust suddenly after reaching their temperature limit

ball drip

automatic drain valve at the bottom of dry standpipe

deluge systems

� Used in high ?re hazard areas to ?ood area in case of a ?re
� Heads are always open and water is controlled by a sensor
� Sprinklers are activated all at once regardless of the location of the ?re

wet standpipe system

� Most common system
� Continually pressurized with water
� Have low initial cost
� Have quick response time, will work when a sprinkler head reaches 135?F - 170?F
� Susceptible to damage from freezing

dry standpipe system

� Used in areas subject to freezing because no water sits in the pipes
� Hold valves closed with compressed air, requires constant pressure else the system will leak
� Slower to deliver water if pipe runs are long

preaction system

� Reduce likelihood of a false start by requiring both a sprinkler head and ?re detection system to be activated
� Water is allowed into the system before a sprinkler head is opened

halon extinguisher

used when water damage might be bad for the room (e.g.: computer rooms)

foam extinguisher

used where ?ammable liquid ?res might occur (e.g.: industrial buildings, aircraft hangers)

intumescent paint

material expands rapidly when exposed to heat
insulating the surface

ionization detectors

used for incipient state
� Have two chambers: a reference and a measuring
� A small amount of radioactive material ionizes the air between the charged surfaces in each chamber which results in current ?ow
� When combustion particles enter the detector, it

photoelectric sensors

used to detect at smoldering stage
� React to visible smoke that blocks a beam of light
� Can measure a large volume of air
� Are useful when potential ?res may produce a lot of smoke before busting into ?ame

heat actuated sensors

used during ?ame stage
� Activated by temperature rise, and ?ames must be present before the alarm temperature is reached

UL

Underwriters Laboratory

ASTM

American Society for Testing Materials

NFPA

National Fire Protection Association

ANSI

American National Standards Institute

smoke developed rating

numerical rating of interior ?nish material derived from a standardized ?re test procedure. The larger the number the greater the density of smoke