book 29 Flashcards
1
Q
What are the four objectives of ventilation?
A
- Save lives
- Assist in firefighter access
- Control horizontal spread of fire
- Reduce possibility of flashover and backdraft
2
Q
What are the two types of ventilation holes?
A
Heat holes (Offensive) Strip Ventilation (Defensive)
3
Q
What is a kerf cut?
A
A single cut, chainsaw width, through the decking
4
Q
How many inches inside the purlin shall the cuts be
to avoid the metal hangers?
A
4-6inches
5
Q
Conventional construction utilizes structural
members that depend on what for their strength?
A
Their size
6
Q
Lightweight construction does not derive its
strength from size, but instead what?
A
Multiple members in compression and tension. If
one member fails, others may fail
7
Q
A single lightweight truss structural member can
span how many feet?
A
70 feet
8
Q
For size up considerations, roofs can be divided
into what categories?
A
Hip, bridge truss, flat, arch, gable, sawtooth
Huntington Beach FAGS
9
Q
In a gable roof, rafters are usually what?
A
2 x 6 or larger, spaced 16” to 24” on center
10
Q
Steep pitched gables can have rafters spaced up
to how far?
A
36 inches
11
Q
How are lightweight gables built?
A
2 x 3 or 2 x 4 inch wood trusses held together by
metal gusset plate connectors
12
Q
What is the most common size for metal gusset
plate connectors?
A
18 gauge steel plates with prongs that penetrate
3/8”
13
Q
What are the strong areas of a gable roof?
A
Ridge and area where rafters cross outside walls
14
Q
What decking is found on conventional and
lightweight gable roofs?
A
Conv - 1 x 4 or 1 x 6 inch space sheathing
LW - 3/8” or 1/2” plywood
15
Q
What is a jack rafter?
A
A rafter that crosses an outside wall but does not
reach the ridge board (may reach the hip rafter)
16
Q
What are the strengths of a hip roof?
A
Ridge board, valley rafter, hip rafter and walls
17
Q
Where are bridge truss roofs found?
A
Various types and sizes of commercial buildings
constructed during the 30s and 40s
18
Q
What are wooden truss members made of in
bridge truss roofs?
A
2 x 12”
19
Q
What rafters are found on bridge truss roofs?
A
2 x 6 or larger
20
Q
What type of sheathing is found?
A
1 x 6” (diagonal or straight)
21
Q
When will you find diagonal vs straight sheathing?
A
Pre-33 Straight, 33 and later Diagonal
22
Q
If modified for the Earthquake Ordinance, what will
be found on top of straight sheathing?
A
Plywood (adds shear strength)
23
Q
Where are bowstring arch roofs found?
A
Commercial structures built in 30s, 40s, and 50s
24
Q
What size lumber comprises the arch trusses and
related members?
A
2 x 12” or 2 x 14”
25
What size are rafters on bowstring arch roofs?
2 x 6 or larger
26
What type of sheathing is found?
Pre-33 Straight, 33 and later Diagonal
27
What are characteristics of a Lamella arch roof?
Egg crate, geometric or diamond patterned roof,
| 2 x 12” wood framing, 1 x 6 sheathing
28
Total roof collapse may occur if what percentage of
| the Lamella’s roof structure is removed by fire?
20%
29
What is largest difference between Arch truss roofs
| and tied truss roofs?
5/8” tie rods are used below each arch member in
| tied truss roofs
30
How is proper tie rod tension maintained?
Turnbuckles
31
What size are rafters on tied truss arch roofs?
2 x 10 or larger
32
What type of sheathing is found?
Pre-33 Straight, 33 and later Diagonal
33
What is the primary hazard of tied truss roofs?
Early failure of the metal tie rods and turnbuckles
34
What is the primary advantage to building a
| Sawtooth roof?
To yield additional light and ventilation for
| manufacturing type occupancies
35
What size are rafters on sawtooth roofs?
2 x 8 or larger
36
What size rafters are on conventional flat roofs?
2 x 6 or larger
37
What sheathing is found?
1 x 6" or plywood if newer
38
What is common spacing for lightweight members
| (wooden I, open web, etc)?
24” on center
39
Where are nailing blocks found?
Perpendicular to the top chords and spaced 4’
40
On an open web roof, the steel tube web members
| are prefabricated from what?
1-2” cold rolled steel tubing
41
How long can spans be with an open web
| member?
70'
42
How long can spans be with a metal gusset plate
| roof?
80’
43
What four major components comprise panelized
| roofs?
1. Beam
2. purlins
3. 2x4” joists
4. plywood decking
44
What is the most common size for a Laminated
| beam (Lam beam)?
6 x 36”
45
How far are purlins spaced?
8'
46
How far are main beams spaced?
12 to 40’
47
What is rafter spacing on a panelized?
24” on center
48
What is a common size for a purlin?
4 x 12”
49
What are the strengths of a panelized roof?
Beams, purlins, building perimeter
50
What are open web bar joist roof characteristics?
1/8” steel (top and bottom chords)
| 5/8” steel bar web supports
51
Steel begins to lose its strength at what temp?
1000 degrees F
52
How thick will a lightweight concrete roof be?
3-4 inches, air entrained mixture (Robertson
| Decking)
53
What blade should be used on the rotary saw
| when ventilating lightweight concrete roofs?
Diamond blade OR carbide tipped
54
What are characteristics of a pre-33 masonry
| building?
- Sand and lime mortar only
- no cement
- Lack of steel reinforcing rods (rebar)
- Exterior walls 13” thick
- Parapet wall around perimeter of roof
- Floor and joists that are “Let” into exterior walls
- Straight roof sheathing
- Floor and roof joists that are “fire cut”
55
How high can parapet walls be on a pre-33?
3 feet above roof line, or 5 feet if facade on front
56
What revisions were made to buildings post-33?
```
Exterior walls at least 9” thick
Masonry walls must have steel rebar
All joints and rafters anchored to exterior walls
Cement used in mortar
Diagonal roof sheathing
```
57
What revisions were made to buildings post-59?
4-6” bond cap on parapets along public walkways
Parapet wall limited to 16” (incl bond cap)
Rafter anchor rods installed every 4 feet (tie
plates)
58
Unreinforced masonry may have what trademarks?
- Rafter tie plates
- Bond beam cap
- Deep recessed windows
- Windows may have arched or straight lintels
- Lime mortar is easily rubbed away
- One row of bricks laid on end (kings row) every
four to seven rows
59
What are safe areas of URM buildings?
Corners, or distance away from building at least
| equal to building height
60
You can estimate the amount of time a structure
| will remain strong by these three factors?
Type of construction
How long fire is burning
Fire intensity
61
Concrete tilt ups can be built up to how many
| stories high?
5 stories
62
The primary dangers in unreinforced masonary
| walls are?
The collapse of front and rear walls
63
Safe areas around URM's are?
Corners and distance equal to height of the walls
64
Plans for ventilation operations should begin by?
ID the direction (horizontal or vertical)
contaminants must travel to exit contaminated
area
65
What are the two basic methods that are utilized to
| pressurize a contaminated area?
Natural and mechanical ventilation
66
Where is the blower placed when performing
| negative pressure ventilation?
INSIDE the structure
67
What are disadvantages of negative pressure
| ventilations?
- Personnel exposed to contaminants to position
blower
- Contaminants drawn through blower, addt'l clean
up of blower
- Blower placed in doorway or window hindering
access/egress and using additional tools
- Blowers not efficient at removing contaminants in
top of room or building
68
Where is the blower placed when performing
| positive pressure ventilation?
OUTSIDE the structure
69
Positive pressure ventilation is how many more
| times effective than negative pressure vent?
approx twice as effective
70
Positive pressure is most efficient when the
exhaust opening is what size in relation to the size
of the entrance opening?
Between 3/4 to 1 3/4
71
What is an indicator that the exhaust opening is not
| large enough?
Exhaust odor in the area to be ventilated
72
Positive pressure has proven effective against
| winds up to what speed?
25mph
73
Effective positive pressure ventilation is dependent
| on?
- Controlling entrance opening
- Path of interior air flow
- Size of exhaust opening
74
Smaller blower should be moved _____ from
| entrance and larger blowers _____?
Small; back
| Large; closer
75
If unequal CFM/size blowers are used in series,
place the larger blower how many feet behind
smaller blower?
2 feet
76
A blower behind another blower increases the the
| capacity of the first blower by how much?
10%
77
Removing screens on windows will increase the
| efficiency by what percent?
50%
78
During overhaul, what PPM of CO is easily
| obtainable?
500ppm to 1200ppm
79
What size home is an 18” blower adequate for?
2000 Sq Ft
80
What concentrations of CO can be fatal in less
| than one hour?
4000 ppm
81
Positive pressure should never be used in place
| of?
SCBA when hazardous atmospheres are
| encountered
82
What are the two different types of elevators?
Cable and hydraulic
83
What two types of cable elevators are there?
Drum type or traction type
84
Drum type elevators are restricted to lifts of what
| height?
150 feet and slow speeds
85
Equipment rooms for hydraulic elevators are
| normally found where?
At the lower level of the building
86
Equipment rooms for hydraulic elevators are
normally found at the lower level of the building,
but can be where?
At any floor level, or 50 to 100’ from the elevator
| shaft
87
Freight elevators can be up to what size/capacity?
12’ x 14’, 3 tons (6,000lbs)
88
The door on the car itself, which travels with the
| elevator is called what?
Inner door, or car door
89
The door that is seen from each floor of the
| building is called what?
Hoistway door
90
Which door actuate the other door?
The car door, or inner door, operates the hoist
| way door
91
What are the four basic types of doors used on
| elevators?
Swing hall, single slide, center opening, two
| speed
92
What size are the gib blocks?
3” wide, 1” high, 1/2” thick
93
Gib blocks are installed every how many inches?
18 inches
94
What purpose do gib blocks serve?
They provide stability to the hoist way door as it
| opens and closes
95
Normal hoist way doors can be expected to utilize
| how many gib blocks?
2 gib blocks
96
What is elevator “overspeeding”?
When an elevator travels at more than 20% of its
| top speed
97
On scene information should consist of the what
| minimum considerations?
- Is there an inoperative elevator?
- Does it contain trapped occupants?
What are their conditions?
- Repair person notified? Their ETA?
- What is the location of inoperative elevator?
- What type of elevator? (hydraulic or cable)
- Where is elevator equipment room?
98
When recycling power, leave off for how long?
At least 30 seconds
99
On hydraulic elevators and SOME cable elevators,
the hoist way doors will open if the elevator is
within how many inches above or below the floor
level?
6 inches
100
On cable elevators, the hoist way doors will open if
the elevator is within how many inches above or
below the floor level?
18 inches
101
When inserting an air bag in between center
| opening doors, where shall the bag be placed?
Near the top
102
An escalator traveling between 90 and 120 feet per
minute can carry up to how many passengers per
hour?
5000 passengers
103
The pickup arm clutch on the hoist way door is
| generally how long on hydraulic elevators?
14” long
104
The pickup arm clutch on the hoist way door is
| generally how long on cable elevators?
36” long
105
Where does Los Angeles get its water?
75% two aqueducts from Sierra Nevada
15% wells in San Fernando Valley
10% Metropolitan Water District
106
How big can trunk lines be in the water distribution
| system?
36” to 10’
107
Where are mains found, and what sizes can they
| be?
Beneath a street and parallel to a curb.
| 2” to 72”
108
What size can customer’s service lines be?
Vary from 1/2” to 12”
109
What two types of shut off valves can be found?
Non-indicating valves and Indicating valves
110
What will be found on an indicating valve?
OS&Y or PIV
111
Are water meters bi-directional?
No. One way flow only
112
What sizes can water meters be?
1/2” to 10” (inlet size)
113
What is a compound meter used for?
Can meter high and low flows, meters are 4” or
| larger
114
What size can detector check valves be?
2” to 10”
115
What psi to dwellings commonly use?
40 to 80psi
116
What size meter will be found at most single family
| dwellings?
1/2“ to 2”
117
What size will a detector check valve be at a single
| family dwelling?
2”
118
For hotels, what size water meter may be found,
| and what size detector check valve may be found?
4” to 6” water meter. 4” to 8” detector check valve
119
What size water meter and detector check valve
| will be found in a high rise?
4" to 10” meter. 4” to 12” detector check valve
120
Ball, cone, or gate valves what size and above
may need to be exercised to completely eliminate
the flow of water?
3 inches and above
121
Fire hydrant gate valves may require how many full
| turns to complete a shutdown?
18 to 26
122
What percentage of hydrants close in a clockwise
| direction?
98%
123
What info shall be communicated to MFC after
| shutting down a hydrant?
Hydrant location
If hydrant has been shut down
Number of valves operated
