Ch. 3 Firefighting problems & structural hazards in the 5 basic types of Bldg. construction

Question 1

FIRE RESISTIVE CONSTRUCTION CLASS 1
In a low rise bldg. smoke spreads by heat, convection currents, fire pressure and wind. In a high rise bldg., you also have smoke spread by what?

Answer 1

HVAC System

Question 2

FIRE RESISTIVE CONSTRUCTION CLASS 1
In the past Class 1 apartment houses did not have central AC but had individual units installed in each apartment. This is changing. HVAC systems may connect public hallways on several floors with ducts and vents. This hall air system may spread ______ & _______ on several floors.
Fill in the blank

Answer 2

Smoke & Heat

Question 3

FIRE RESISTIVE CONSTRUCTION CLASS 1
Automatic closing shutters in the air supply ducts are designed to close at a specific temperature. This heat activated damper may stop the flame spread, but does not stop the spread of _______ throughout the system’s air ducts

Answer 3

Smoke

Question 4

FIRE RESISTIVE CONSTRUCTION CLASS 1

During a fire in a modern building, the IC should order bldg. management to shut down what?

Answer 4

The Central air system serving the living space and the hallways.

Question 5

FIRE RESISTIVE CONSTRUCTION CLASS 1

Experience has shown that FF’s operating hoselines can not extinguish fires in floor areas over how many square feet?

Answer 5

5000 square feet

Question 6

FIRE RESISTIVE CONSTRUCTION CLASS 1
Of the 5 basic construction types, fire resistive bldg.'s are the most stable. there are 2 basic types of class 1 bldg.'s reinforced concrete and structural steel. the collapse danger in these bldg.'s at serious fires lies in the?

Answer 6

Concrete

Question 7

FIRE RESISTIVE CONSTRUCTION CLASS 1
In reinforced concrete bldg.’s the heated concrete ceilings can collapse on top of FF’s. Internal pressure in the concrete can cause heavy sections of concrete to crack away from the ceiling and collapse down. The rapid expansion of the heated moisture inside the concrete is known as?

Answer 7

Spalling

Question 8

FIRE RESISTIVE CONSTRUCTION CLASS 1
In steel skeleton bldg.’s heat reaches the underside of the fluted metal deck and is conducted through the concrete floor directly above. The bottom of the concrete cannot collapse downward because of the supporting steel, so the expanding moisture explodes the concrete floor upwards. The floor cracks and erupts upwards. How far?

Answer 8

Several inches

Question 9

FIRE RESISTIVE CONSTRUCTION CLASS 1
NEW
General Info

Answer 9

• If the fire is severe, the steel beams supporting the fluted metal deck start to expand, and if the steel beams are restricted, they start to sag and bow downward, causing the concrete to also sag and bow downward
• When heated, a concrete floor can crack and allow heat, smoke and flame to spread to the floor above
• At a serious fire in a Class 1 bldg., the composite, concrete and fluted metal deck will be damaged because the steel expansion is greater than the concrete when heated by the fire. The composite, concrete and metal decking are the collapse hazard.

Question 10

NON/LIMITED COMBUSTIBLE CLASS 5
When a fire occurs in these bldg.’s the IC should have a FF check the roof covering over the fluted metal deck for fire extension, as heat may have conducted through the metal roof deck and ignited the combustible roof covering.
He should do this as soon as the fire is?

Answer 10

Darkened down

Question 11

NON/LIMITED COMBUSTIBLE CLASS 5
The IC should order a COMPANY to the roof to check the combustible asphalt roof covering as heat may have conducted through the steel fluted roof deck and ignited the roof covering.
He should do this as soon as the fire is?

Answer 11

Under Control

Question 12

NON/LIMITED COMBUSTIBLE CLASS 5

The collapse danger in Non/Limited combustible bldg.’s is?

Answer 12

Roof cave in (the collapsing material is the steel open web bar joists)

Question 13

NON/LIMITED COMBUSTIBLE CLASS 5
The main advantage of the lightweight steel support is its non combustibility. The main disadvantage is the open web bar joists are susceptible to damage by fire. Unprotected lightweight open web steel joists can fail when exposed to fire for how many minutes?

Answer 13

5-10 minutes

Question 14

NON/LIMITED COMBUSTIBLE CLASS 5

What other natural occurrence can cause the collapse of the roofs of these bldg.’s?

Answer 14

Heavy snow falls

Question 15

NON/LIMITED COMBUSTIBLE CLASS 5

Are the roofs of these bldg.’s designed to support FF’s during fires?

Answer 15

No these roofs are not designed to support FF’s during fires.

Question 16

NON/LIMITED COMBUSTIBLE CLASS 5

NYC Bldg. code prohibits open web steel bar joists in high rise construction bldg.’s since what date?

Answer 16

9/11/2001

Question 17

BRICK & JOIST CONSTRUCTION CLASS 3
The major fire problem in an ordinary constructed bldg. is the fire and smoke spread throughout concealed spaces. The largest and most serious concealed space is the?

Answer 17

Common Cockloft-the space above the ceiling and below the roof.

Question 18

BRICK & JOIST CONSTRUCTION CLASS 3
There are many concealed spaces, voids and poke through openings hidden behind the plaster walls, ceilings and floors. As soon as possible after the fire is extinguished in a class 3 bldg. a FF MUST be directed to open up what 2 areas to examine for fire spread to concealed spaces?

Answer 18

The CEILING above the fire and nearby WALLS

Question 19

BRICK & JOIST CONSTRUCTION CLASS 3

If fire is discovered in a concealed space what MUST be checked for fire, prior to FD units leaving the scene?

Answer 19

The cockloft space above the top floor.

Question 20

BRICK & JOIST CONSTRUCTION CLASS 3

What is the major collapse hazard in a brick & joist ordinary construction bldg.?

Answer 20

The parapet wall

Question 21

HEAVY TIMBER CONSTRUCTION CLASS 6
These 4-7 story, bricked wall bldg.’s, originally designed for textile mills, used large wooden timbers to support heavy machinery and are very stable bldg.’s. The major fire problem is?

Answer 21

The Large wooden interior timber framework

Question 22

HEAVY TIMBER CONSTRUCTION CLASS 6
For a bldg. to qualify as heavy timber:
-A wood column cannot be less than ___ inches thick.
-A wood girder cannot be less than ___ inches thick.
Fill in the Blanks

Answer 22

Column-8”

Girder-6”

Question 23

HEAVY TIMBER CONSTRUCTION CLASS 6
The advantages of not enclosing ceilings or the timber in plaster are that there will be no concealed spaces, no obstructions to the FF’s hose stream, and no hidden what behind ceilings and walls?

Answer 23

Flames or Fire

Question 24

HEAVY TIMBER CONSTRUCTION CLASS 6
The disadvantages of not enclosing the ceilings or timber is if initial firefighting efforts are unsuccessful and a exterior attack is required, a Class 6 bldg. will experience a large fire, and radiant heat from the windows will ignite adjoining structures. Radiant heat waves can travel distances up to how many feet?

Answer 24

80 feet

Question 25

HEAVY TIMBER CONSTRUCTION CLASS 6

The major collapse hazard in these bldg.’s is what?

Answer 25

Falling masonry walls-very few FF’s are killed by these falling walls because the radiant heat keeps them away from the front of the bldg.

Question 26

WOOD FRAME CONSTRUCTION CLASS 4
Officers normally consider the possibility of extension to the “6 sides” of the fire-above, below, and the four side walls. Wood frame bldg.’s have a 7th side that MUST be considered.
What is the 7th side of wood frame bldg.?

Answer 26

The combustible exterior walls

Question 27

WOOD FRAME CONSTRUCTION CLASS 4
Closely grouped wood houses can present fire companies with a fast spreading fire on the outside walls, in addition to the interior fire. Fire spread to nearby structures can be reduced by the use of non combustible siding and by providing distances of how many feet between frame bldg.’s?

Answer 27

10-20 feet

Question 28

WOOD FRAME CONSTRUCTION CLASS 4
The structural hazard of a wood frame bldg. is the combustible bearing wall constructed of 2x4” wall studs. The structural supports of the side bearing walls are only 2x4 inches in size yet they support wood floor joists and roof joists of 2x10”s in size.
Which structural member is the weak link in this construction?

Answer 28

The 2x4” wall stud

Question 29

WOOD FRAME CONSTRUCTION CLASS 4
Flames coming out the windows of a side bearing wall should be treated with more caution than a front or rear wall. Fire burning through or against a side wall is more likely to collapse the bldg., than fire burning through several floors or the roof. Failure of a bearing wall will trigger simultaneous failure of what? ( 2 answers)

Answer 29

The floors and roof