Ch. 5 Fire Behavior and Bldg Constr. Flashcards Preview

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Flashcards in Ch. 5 Fire Behavior and Bldg Constr. Deck (67):

Fixed or movable walls and partitions, columns, and ceilings. Commonly refers to finish on walls and ceilings, NOT FLOOR COVERINGS.

Interior finish
*plaster, gypsum wallboard, wood paneling, ceiling tiles, plastic, fiberboard*


Combustibility of interior finish affects fire behavior: (4)

Contributes to fire extension by flame SPREAD over surface of walls and ceilings.
Affects rate of fire GROWTH (flashover).
Adds to INTENSITY (fuel).
Can produce smoke/toxic GASES (life hazard)


Incidental trim considered trim as long as: (2)

-doesn't exceed 10% of wall AND ceiling.
-doesn't constitute "a large continuous surface"


Bldg code exclude surface treatments that are no thicker than ______. A thin product, ______, will propagate flame more quickly with studs and air space, than attached directly to more solid material.

NO thicker than 1/28th in.



Degree to which fire can spread over the surface of a material is technically referred to as the _____ of a material.

Surface burning characteristics


Speed of flame spread over an interior finish influenced by:

-composition of material
-shape of space in which material is installed
-whether finish of material is applied to ceiling or wall


Interior features such as ____, ____, and _____ have a CUMULATIVE effect on the outcome of a fire event.

-wall coverings
-fire protection systems


Total amount of heat produced or released to the atmosphere from the CONVECTIVE LIFT PHASE of fire per unit mass of fuel consumed per unit time.

Heat release rate (HRR)


_______ is not by itself a measure of the severity or rate of fire development of a fire. The severity of a fire is determined by _________ plus ___________.

Fire load.

Fire load.
The rate at which the fuel burns


Rate at which fuel burns is determined by several factors. The most important is the ___________.

Combination of fuel and available oxygen.


The tunnel test, NFPA 255, produces a _______ rating of the flammability of the interior materials, which is known as the ______.

Flame spread rating


NFPA 255, UL 753, ASTM E84 Tunnel Test (Steiner) dimensions and temperature

25 ft long horizontal furnace.
17 5/8 in. wide.
12 in. high.

4 1/2 ft. flame.
5,000 btu's
10 minutes


Three classifications of interior finishes

Class A-0-25, VERTICAL exits.
Class B-26-75 CORRIDORS that provide EXIT access.
Class C-76-200 other ROOMS and SPACES depending on occupancy
*rooms of healthcare and assembly occupancies*


To derive numerical rating for NFPA 255 Steiner Tunnel, flame spread compared to two standard materials:

Asbestos cement board 0.
Red oak flooring 100.

Fire spread along red oak flooring 24 ft in 5 1/2 minutes


The tunnel test provides an additional measure of flammability: ___________.

The smoke developed rating.
(Photoelectric cell and light source at end of tunnel furnace)
Red oak standard-100 smoke developed rating.
Codes limit max smoke developed to 450


Fire retardant coatings (4)

Intumescent paints-expand upon exposure to heat.
Mastics-thick, noncombustible coating.
Gas-forming paints.
Cementitious and mineral fiber coatings
**do not increase fire resistance of structural components unless tested**


Fire retardant coatings-
Must be applied at a __________________. May not have permanent effect if used in ___________ or ______________. Fire retardant coatings only affect ___________, not the ____________.

Specified rate of square feet per gallon

In exterior applications OR environments with high humidity

Coated surface, untreated back side of a panel


Tunnel test (255/ASTME84/UL753) is useful because:

-it provides REPRODUCIBLE results AND
-is a widely RECOGNIZED standard


Smoke developed rating ______ an indication of toxicity or volatility. Tunnel ________ detect or measure a completely transparent product of combustion.



Materials produce fire hazard greater that tunnel test because: (2)

Flame spread different over a vertical surface than horizontal surface.
Walls and ceiling provide for re-radiation of heat between intersecting surfaces


NFPA 265 is _____________

"Evaluating room fire growth contribution of textile coverings on full height panels/walls" originally developed carpet-like textiles began to be used as wall coverings


NFPA 286 is ____________.

"Contribution of wall/ceiling interior finish to room" to handle materials that may not remain in place during tunnel test (plastics that melt and drip)
*IBC allows 286 instead of steiner. No flashover, max 800kW.*


2 basic fire protection concepts are:

Active - have a power source, source can be manual=fire extinguisher. Ex. sprinkler or alarm
-extinguishes or controls fire.
Passive - relies on bldg constr. and materials. Ex. firewalls, stair enclosure, fire doors.
-limits spread


Partitions separating individual rooms within an apartment are ___________.

NOT fire rated


Assemblies of building components required by code to have a minimum fire-resistance rating from independent testing agency. Also called _______.

Rated assembly


_______ can provide areas of refuge for occupants when immediate/rapid evac is not possible. Concept of providing an area of refuge is referred to as ________ or ________.

Fire-rated partitions.

Defending-in-place OR sheltering in place
*requires INTERVENING doors be CLOSED*


Fire walls can be constructed as "freestanding walls" or as "tied walls". Freestanding walls are _______ and ________.

Independent of the building frame (bldg may provide horiz. support).
*Usually found in wood-frame or wood-joisted masonry (Type III or IV)*


Wall that is self-supporting to vertical loads and can withstand lateral force of AT LEAST 5 lbs per sq. ft. and self-supporting with respect to Vertical loads.

Freestanding wall (fire wall)


______, or AREA SEPARATION WALLS, are erected to limit the maximum spread of fire. Constructed with sufficient fire resistance and structural stability to act as an __________ to fire under conditions of total burnout on ______.

*freestanding and tied*

Fire walls.
Absolute barrier.
Either side


Recent building codes permit fire walls with fire-resistive ratings of _________, depending on occupancy. 4 hr firewall must have _____ rated openings.

2, 3 or 4 hrs.
3 hr


IBC permits combustible structural members to be framed into masonry or concrete fire wall from opposite sides provided there is a ___________ between the ends of the structural members.

4 in. separation


Fire walls must _________ to prevent radiant heat from igniting adjacent surfaces. Accomplished by continuing the wall through the roof with a _____. Parapet height above combustible roof varies from ________.

Extend beyond walls and roofs.
18 to 36 in.


_______ are erected at ________ in a bldg of steel-frame or concrete frame construction. Must resist _____________ on either side.

Tied fire walls, A column line

Lateral pull of the collapse


Some bldg codes contain exceptions that permit elimination of parapets under certain conditions, such as fire wall can ____________ that has a covering of low combustibility.

Terminate at the underside of a noncombustible roof


Non-freestanding firewalls that DO NOT have parapets are ________ from the outside. Particularly true for fire walls with ____ rating constructed of materials OTHER than _____.

Not readily identifiable.


______ are interior walls used to subdivide a floor or area of a building that DO NOT qualify as fire walls OR

Fire barrier that extends from one floor to bottom of floor above OR to underside of a fire-rated ceiling assembly

Fire partitions


Fire partitions can be constructed from a wide variety of materials including ____, _____, _____ and ___________. Materials chosen depend on _____ and _____.

Lath and plaster.
Gypsum wallboard.
Concrete block.
Combination of materials.

Required fire resistance.
Construction type of building.


Enclosure and shaft walls
-required to have fire resistance rating of _________ hrs depending on height of building.
-stairwells in bldgs 3 stories or less ____
-stairwells in bldgs more than 3 stories ______

1-2 hrs.


Partition walls separating adjacent units in an apartment building may be required to have a __________.

1 hr fire resistance
*steel studs with 5/8" fire-rated gypsum board*


Enclosure walls are load bearing or non-load bearing?

Non, except for older mill bldgs-masonry stair enclosures


Light shafts can provide a ____________ of fire from window to window.

Means of vertical communication
*HOT vertical AND horizontal*


Two aspects of curtain walls are significant to firefighters:

Degree of fire resistance - non-load bearing so lacks fire resistance.
Vertical communication of fire - gaps between wall and floor/ceiling


Building codes require exterior walls-including curtain walls- have some degree of fire resistance between buildings. This resistance depends on:(2)

Separation DISTANCE between buildings AND


Fire doors differ from ordinary doors in: (3)



Fire doors are rated as:
Meant to describe the opening but historically have been used to __________.

Describe the door itself

4, 3, 1 1/2, 1, 3/4, 1/2 and 20 minutes
*1/2 and 1/3 used in smoke barriers*


Existing fire doors have been classified by using ______, ______, or both. (5)

Letter designation, an hourly rating.

A-fire walls.
B-vertical shaft and openings 2 hr rated partitions (stairwells).
C-rooms/corridors 1 hr or less.
D-exterior walls SEVERE fire exposure from outside.
E-exterior walls MODERATE to LIGHT fire exposure from outside


Classification of a fire door is known as its "fire _______ rating", and is not to be confused with the fire ______ rating used to describe structural components.



NFPA _____ standard method of fire tests of door assemblies

252/ASTM E-152


Criteria for fire door acceptability:

Door remain in place (primary criteria)
-some warping permitted
-flame passage after 30 minutes.
Door assembly must remain in place WHEN SUBJECT TO HOSE STREAM (second criteria)
-1/3 hr doors may not be subject to hose stream


Fire doors identified with label indicating: (3)

-door type
-hourly rating
-testing lab


Builders hardware:

Swinging door

Shipped SEPARATE from door


Fire door hardware

Swinging AND sliding.
Hardware shipped with door


Glazing is often NOT provided by the door manufacturer and may be installed ______________. NFPA ____, standard for fire doors and fire Windows.

By a glazing contractor


Glass in fire doors

100 sq in = 1, 1 1/2 and 3 hr doors.
1,296 sq in or consistent with listing = 3/4 hr.
Up to max area tested = 1/3 and 1/2.


Smooth galvanized sheet metal on wood-core doors is:

Kalamein door
"Smooth as kalamein"


Galvanized steel or terneplate referred to as:

Tin clad door


Failure of fire doors common-Reasons for failure of fire door:

-damage to door closer
-the door itself
-door guides


Swinging, sliding or rolling.
Used with suitable door closer.
Electromagnetic in conjunction with smoke detector.
Prevents blocking of door.
Closes quickly.
Health care occupancies

Door holder


Sliding or swinging fire doors.
Hold open device or self closing.
Fusible link.
Commonly used is spring hinge.
Self closing used for stairwell doors or doors that separate hotel rooms from corridors.

Fire door CLOSER


Used with sliding fire doors mounted on level or inclined track.
Electric operator that opens/closes for normal use.
Fusible link disconnects door from operator
-allows it to close by means of spring-powered door closer or suspended weights

Door operators


For a door in normally open position to close, some type of OPERATING DEVICE must first sense fire or smoke from fire.
Oldest and simplest:

Oldest/simplest:fusible link
-relatively rugged
-BUT slower to operate
Smoke detector
-door closes quicker
-permits easy testing
-BUT costs more and must be properly positioned


Louvers in a fire door:

Usually closed by fusible link.
Swinging doors with ratings up to 1 1/2 hrs can be equipped.
Louvers may not be produced by door manufacturer.
Listed separately by testing labs.
Cannot be arbitrarily installed.
Only doors listed for installation of lovers can have them


Very common-stairwell enclosures and corridors.
Disadvantage-clear space.
Ratings of 3 hrs to 20 minutes.
Large variety available

Swinging fire doors


Used to protect opening in industrial occupancy OR
at opening in wall separating bldgs.
May be used on one or both sides of opening.
Architectural advantage-inconspicuous and out of the way
Interlocking steel slats.
Closes under force of gravity when fusible link melts.
-May create dangerous dead-end corridor when closes
FF's can't see-avoid being struck by closing door

Rolling steel fire doors (overhead rolling)


Freight/passenger elevators.
Service counter openings.
Security (bullet-resistant).
Horizontal folding door (motor-driven, requires electrical power)
-smoke detector/fire alarm. Fire partition required but no fixed wall)

Special fire doors


Often found in OLDER industrial bldgs.
Held open by fusible link.
Slide into position by gravity or counterweight.
Metal covered, wood core.
Vent hole to vent gases of decomposition.
Kalamein and tin clad door.

Horizontal sliding door


This type of door ESPECIALLY subject to damage. Also closing mechanisms are 1)more complicated and 2)typically more inconspicuous.

Overhead (fire) doors