Chapter 14

Question 1

The ISO’s key responsibility is to recognize incident hazards and make corrective recommendations to prevent injuries to responders.

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Question 2

The ISO must check in with the IC and, after receiving a briefing, conduct an independent 360 degree assessment of the incident.

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Question 3

High humidity can cause smoke to remain close to the ground, obscuring visibility of the building.

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Question 4

The ISO must continuously monitor wind velocity and direction to ensure personnel and hose streams are not placed in a windward position.

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Question 5

Generally, wind speeds greater than 20 mph will reduce aerial ladder load capacity.

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Question 6

Personnel operating at a scene with high intensity activity must be provided proper work/rest periods and follow the recommendations in NFPA 1584, standard on the rehabilitation process for members during emergency operations and training exercises.

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Question 7

Cardiac related events at emergency incidents are a leading cause of firefighter illness and death.

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Question 8

It is critical that medical surveillance monitoring and proper rehabilitation is established at emergency and planned events.

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Question 9

High noise levels can also lead to a condition called tunnel hearing.

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Question 10

Tunnel hearing can cause people to concentrate so closely on one task that they lose their sense of situational awareness.

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Question 11

Longer shifts equate to lessened situational awareness, which increases the risk of injury.

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Question 12

Research shows that fires go through four distinct stages: incipient, growth, fully developed, and decay.

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Question 13

ISOs should assume that an entire structure is the compartment that fire is affecting rather than just the compartment of origin.

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Question 14

Open interior doors, hallways, and stairwells connecting rooms extend the possible growth potential of a fire beyond its compartment of origin.

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Question 15

At a fire scene, the stages of fire development are a guide for what could occur during the fire but are not a pattern of what will occur every time.

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Question 16

The ISO should forecast fire spread based on fire department suppression efforts and conduct an ongoing assessment of hazards as they relate to the stages of fire growth.

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Question 17

The type of fuel involved in combustion affects the heat release rate.

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Question 18

Fires involving class B and C fuels will eventually spread to the building contents and structure, resulting in a primarily class A fueled fire.

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Question 19

In a compartment fire, surface to mass ratio is one of the most fundamental class A fuel characteristics influencing fire development.

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Question 20

Combustible materials with high surface to mass ratios are much more easily ignited and will burn more quickly than the same substance with less surface area.

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Question 21

Fires involving class B flammable/combustible liquids will be influenced by the surface area and type of fuel involved.

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Question 22

A liquid fuel spill will increase that liquid’s surface to volume ratio generating more flammable vapors than the same liquid in an open container.

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Question 23

Burning synthetic fuels produces products of combustion that contain large quantities of solid and liquid particulates and unburned gases.

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Question 24

Heat release rate - total amount of heat produced or released to the atmosphere from the convective lift phase of a fire, per unit of mass of fuel consumed per unit time.

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Question 25

Just like with solids, an increase in a liquid’s surface area correlates to the generation of more flammable vapors.

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Question 26

A compartment fire that results from a flammable/combustible gas leak may begin with a rapid ignition of the gas and an explosion.

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Question 27

Factors that influence the availability and location of additional fuels include the building configuration, construction materials, contents, and proximity of the initial fire to these exposed fuel sources.

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Question 28

In buildings where the construction materials are flammable, the materials themselves add to the structure’s fuel load.

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Question 29

Plywood is easily ignited, even while level and horizontal, because it has a high surface to mass ratio.

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Question 30

The contents of a structure are often the most readily available fuel source, significantly influencing fire development in a compartment fire.

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Question 31

When contents rapidly release a large amount of heat, both the intensity of the fire and speed of development will be increased.

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Question 32

Polyurethane foam has a high surface to mass ratio and will continue to burn after it has liquefied.

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Question 33

Pyrolize - description of the process of a solid beginning to emit gases due to heat exposure.

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Question 34

Fuels located in the upper level of adjacent compartments will pyrolize more quickly from the effect of the hot gas layer.

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Question 35

Residential structures built after 1990 burn hotter, faster, and produce more smoke with flammable properties than traditional or legacy construction.

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Question 36

Slower fire development is due to the greater volume of air and the increased distance radiated heat must travel from the fire to the contents that must be heated.

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Question 37

A large volume of air will support the development of a larger fire before the lack of ventilation becomes the limiting factors.

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Question 38

Ventilation in a compartment significantly influences how fire develops and spreads.

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Question 39

When sufficient oxygen is available, the characteristics and configuration of the fuel control fire development, Under these conditions, the fire is said to be fuel-controlled.

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Question 40

Fuel controlled - A fire with adequate oxygen in which the heat release rate and growth rate are determined by the characteristics of the fuel, such as quantity and geometry.

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Question 41

Ventilation controlled - Fire with limited ventilation in which the heat release rate and growth is limited by the amount of oxygen available to the fire.

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Question 42

When the available air supply begins to limit fire development in a compartment fire, the fire is said to be ventilation controlled.

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Question 43

When a fire becomes ventilation controlled, the available supply will determine the speed and extent of fire development and the direction of fire travel.

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Question 44

When considering fire development, personnel should consider potential openings that could change the ventilation profile under fire conditions.

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Question 45

Bi direction flow paths, sometimes created by the task ventilation, can be deadly to firefighters and civilians inside the structure.

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Question 46

When the fire becomes ventilation controlled, the fire’s HRR will decrease.

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Question 47

Heat reflectivity - increases fire spread through the transfer of radiant heat from wall surfaces to adjacent fuel sources.

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Question 48

Retention - maintains temperature by slowly absorbing and releasing large amounts of heat.

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Question 49

Ambient conditions, such as high humidity and cold temperatures, can slow the natural movement of smoke.

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Question 50

If a window fails or a door is opened on the windward side of a structure, fire intensity and spread can increase significantly, creating a blowtorch effect.

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Question 51

A compartment’s thermal properties contribute to the accumulation of heat.

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Question 52

Cold temperatures can cause smoke to appear white and give a false impression of the interior conditions based upon the color of smoke.

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Question 53

Atmospheric air pressure can also cause smoke to remain close to the ground, obscuring visibility during size up.

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Question 54

A ceiling jet convects heat through the ceiling, which in turn radiates heat back down toward the room some distance away.

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Question 55

Unconfined fires draw air from all sides and the entrainment of air cools the plume of hot gases, reducing flame length an vertical extension.

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Question 56

When the fuel package is not in the middle of the room, the combustion zone expands vertically.

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Question 57

The expanded combustion zone increases both the temperatures in the developing hot gas layer at ceiling level and the spread of the ceiling jet.

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Question 58

The thermal layering of gases, sometimes referred to as heat stratification and thermal balance, is the tendency of gases to form into layers according to temperature.

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Question 59

Changes in ventilation and flow path can significantly alter the thermal layering.

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Question 60

As the volume and temperature of the hot gas layer increases, so does the pressure.

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Question 61

The interface of the hot and cooler gas layers at the opening is commonly referred to as the neutral plane because the pressure is neutral where the layers meet.

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Question 62

The neutral plane will lower as the fire burns the available fuel in the compartment.

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Question 63

During the development of a compartment fire, pyrolysis of exposed fuels can produce combustible gases, which can gather at locations in the layer some distance away from the fire plume.

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Question 64

Radiated heat from a fire can pyrolize nearby materials.

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Question 65

Use effective fire control and ventilation tactics to raise the position of the hot gas layer.

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Question 66

As the fire moves through the growth stage and becomes ventilation controlled, isolated flames may be observed moving through the hot gas layer.

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Question 67

Rapid transition from the growth stage to the fully developed stage is known as flashover.

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Question 68

Most fires that develop beyond the incipient stage become ventilation controlled.

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Question 69

Under laboratory conditions or when fire is fuel controlled, flashover occurs during the growth stage.

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Question 70

The fully developed stage occurs when all combustible materials in the compartment are burning.

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Question 71

Increases in the available air supply will result in higher heat release.

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Question 72

A compartment fire will decay as the fuel is consumed or if the oxygen concentration falls to the point that flaming combustion is diminished.

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Question 73

As the fire consumes the available fuel in the compartment and the heat release rate begins to decline, it enters the decay stage.

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Question 74

If there is adequate ventilation, the fire becomes fuel controlled.

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Question 75

When a compartment fire enters the decay stage due to a lack of oxygen, the rate of release also declines.

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Question 76

When a flashover occurs, the combustible materials in the compartment and fuel gases ignite almost simultaneously, resulting in full room involvement.

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Question 77

Flashover typically occurs during the growth stage of a fire but may occur in the fully developed stage.

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Question 78

During flashover, the volume of the fire can increase from approximately 1/4 to 1/2 of the room’s upper volume filling the entire volume of the room and potentially extending out of any openings in the room.

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Question 79

Regardless of the type, quantity, or configuration of fuel, heat release is dependent on oxygen.

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Question 80

While no exact temperature is associated with flashover, it typically occurs at 1,100*F ceiling temperature.

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Question 81

Rollover describes a condition where the unburned fire gases that have accumulated at the top of a compartment ignite and flames propagate through the hot gas layer across the ceiling.

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Question 82

Rollover may occur during the growth stage as the hot gas layer forms at the ceiling of the compartment.

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Question 83

A ventilation controlled compartment fire can produce a large volume of flammable smoke and other gases due to incomplete combustion.

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Question 84

An increase in low level ventilation prior to upper level ventilation can result in an explosively rapid combustion of the flammable gases, called backdraft.

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Question 85

Backdraft occurs in the decay stage, in a space containing a high concentration of heated flammable gases that lack sufficient oxygen for flaming combustion.

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Question 86

A smoke explosion may occur before or after the decay stage.

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Question 87

Smoke explosions are violent because they involve premixed fuel and oxygen.

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Question 88

Fire is controlled and extinguished by limiting or interrupting one or more of the essential elements in the combustion process.

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Question 89

Cooling low flashpoint flammable liquid with water cannot sufficiently reduce vapor production.

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Question 90

Water absorbs significant heat as its temperature is raised, but it has its greatest effect when it is vaporized into steam.

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Question 91

When water is converted to steam at 212*F, it expands approximately 1,700 times.

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Question 92

Firefighters can control steam production by: using good nozzle technique, applying the appropriate amount of water, applying water using the most effective form.

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Question 93

The simplest method of fuel removal is to allow a fire to burn until all fuel is consumed.

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Question 94

Reducing the oxygen available to the combustion process reduces a fire’s growth and may extinguish it over time.

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Question 95

Flooding an area with an inert gas, such as carbon dioxide, displaces oxygen an disrupts the combustion process.

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Question 96

Door control - firefighting tactic intended to reduce available oxygen to a fire and create a controlled slow path in a structure for tactical ventilation, firefighter survivability, and occupant survivability.

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Question 97

Blanketing foam prevents oxygen from mixing with fuel gases which in turn inhibits the combustion process.

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Question 98

Unplanned ventilation can result from wind outside the structure.

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Question 99

Wind can affect ventilation operations and may also create a pressure differential between the interior and exterior pressures which causes windows to fail.

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Question 100

Tactical ventilation is the planned, systematic, and coordinated introduction of air and removal of hot gases and smoke from a building.

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Question 101

Increased ventilation to a ventilation controlled fire will quickly result in an increase in the heat release rate.

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Question 102

Even with coordinated tactical ventilation, there will be an increase in the combustion rate when the fire is ventilation controlled.

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Question 103

Smoke volume is the quantity of smoke visible.

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Question 104

Volume pushed smoke will usually flow neither smooth nor turbulent.

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Question 105

High neutral plane may indicate that the fire is in the early stages of development.

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Question 106

Mid-level neutral plane could indicate that the compartment has not ventilated yet and that flashover is approaching.

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Question 107

Very low level neutral plane may indicate that the fire is reaching backdraft conditions.

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Question 108

There are three ways to describe how smoke moves: floating or hanging, volume pushed, and heat pushed.

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Question 109

The heat within the smoke will dictate speed.

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Question 110

Floating smoke is the same temp as the air around it and is often found in air conditioned buildings or fires that are sprinkler controlled.

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Question 111

Floating or hanging smoke will move according to air currents and indicates a small, early stage fire, mostly containing moisture from the first stage of pyrolysis.

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Question 112

Fast exiting smoke indicates a large fire and or a high rate of fire spread.

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Question 113

If the fire is under-ventilated, pressurization can reduce flame action.

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Question 114

Turbulent black smoke has lots of particles and, indicative of vent controlled smoke, has heat.

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Question 115

Laminar/straight line smoke that is thin and fast moving is heat pushed, not under ventilated, and is exiting from opening near active flaming fire.

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Question 116

Smoke color and location are possible indicators of the location of the fire, its intensity, and possibly the fuel being consumed.

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Question 117

Tar, soot, and carbon are the most common heated particles found in smoke, giving it the black color.

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Question 118

Moisture and heated gases give the smoke its white color.

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Question 119

Light white smoke indicates that pyrolysis is occurring in areas adjacent to the main body of fire.

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Question 120

When a product is heated at a consistent temp, it can pyrolize and release types of flammable gases.

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Question 121

Brown smoke is common in mid-stage heating as moisture mixes with gases and carbon as pyrolysis increases.

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Question 122

Caramel colored smoke usually indicates clean wood burning, such as a fire involving structural wood members.

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Question 123

Gray smoke indicates a combination of mixing smoke colors.

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Question 124

Black smoke contains high quantities of carbon particles and is an indicator of the amount of ventilation available at the seat of fire.

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Question 125

The darker and more turbulent the smoke is, the closer you are to a rapid fire event.

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Question 126

The denser the smoke, the lower the visibility, and the more likely that heat build up indicates a pending flashover.

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Question 127

Thin black smoke is the direct result of heat from a flame.

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Question 128

The term black fire refers to a dark black, thick, turbulent smoke that is ready to ignite.

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Question 129

When black fire is present, applying water to cool the ceiling area is encouraged in an effort to reduce the potential for a flashover.

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Question 130

Flow path is the movement of fresh air toward the base of a fire and the movement of smoke and heated gases out of a structure, understanding this phenomenon can help in the ventilation of a fire.

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Question 131

Heat is a form of energy transferred from one body to another as a result of a temperature difference.

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Question 132

Double paned windows resist failure due to heat, however, the interior pane may be cracked due to heat.

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Question 133

Blistered paint indicates both extreme temperature and location of the neutral plane.

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Question 134

Flame color is usually an indicator of the oxygen supply and the extent of fuel-oxygen pre-mixing, which determines the rate of combustion.

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Question 135

Fire growth requires sufficient oxygen, and flames will naturally seek out the path of least resistance toward the available oxygen.

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Question 136

Type 1, fire resistive, construction provides the highest level of protection from fire development and spread as well as collapse.

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Question 137

Fire resistance is required to be 3 to 4 hours depending on the component.

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Question 138

Reinforced concrete and precast concrete along with protected steel frame construction meet the criteria for type 1 construction.

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Question 139

Type 2 construction is normally used when fire risk is expected to be low or when fire suppression and detection systems are designed to meet the fuel load of the contents.

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Question 140

Type 3 ordinary construction is commonly found in churches, schools, mercantile buildings, and residential structures.

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Question 141

Type IV construction, heavy timber, is characterized by the use of large dimensional lumber.

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Question 142

Type V construction is commonly known as wood frame or stick frame.

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Question 143

NFPA 501, standard on manufactured housing, addresses criteria for manufactured homes.

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Question 144

Manufactured homes are the most common type of factory built homes, almost completely prefabricated prior to delivery, and the least expensive.

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Question 145

Current estimates indicate that manufactured homes make up 25 percent of all housing sales in the U.S.

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Question 146

Manufactured homes built before 1976 have less fire resistance than those of current construction.

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Question 147

NFPA analysis of fires in residential occupancies indicates a steady decline in fires in manufactured homes since 1980.

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Question 148

Only about 6 percent of all factory built housing starts are modular homes.

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Question 149

Almost 1 million residential roof structures were constructed utilizing fire retardant plywood sheathing, these roofs disintegrate rapidly and only had a maximum 10 year lifespan.

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Question 150

Laminate beams - structural members created from layers of composite plywood or OSB.

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Question 151

It is estimated that more than 60 percent of roof systems are constructed using a truss system.

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Question 152

Bowstring trusses apply outward pressure to exterior walls, which could contribute to collapse under fire conditions.

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Question 153

Rain roof - second roof constructed over an existing roof.

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Question 154

Protected and non-protected lightweight construction assemblies fail much faster than legacy construction assemblies.

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Question 155

Temperatures at the bottom of basement stairs were often higher than those encountered at the top of the stairs.

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Question 156

In 10 minutes, a master stream delivering 250 gallons per minutes can add approximately 10 tons of weight to the structural components.

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Question 157

The size up assessment should provide critical decision making information about the access and egress points available.

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Question 158

Thermal and photovoltaic are two types of solar power systems that fire and emergency personnel are most likely to encounter.

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Question 159

Treat the solar power system and panels as Class C fire.

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Question 160

Knowing the construction material and how fire affects the materials will assist in the risk benefit analysis.

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Question 161

Every gallon of water that is used to suppress the fire adds approximately 8 pounds of weight to floors that may already be weakened.

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Question 162

Natural gas is an odorless gas that is lighter than air.

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Question 163

If natural gas is leaking from an underground line, fire crews should use a fog stream to disperse the concentration of gas at the site and reduce the chance of an explosion.

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Question 164

Propane, an odorless gas that is heavier than air, is transported by railcar and tanker truck.

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Question 165

OSHA defines a pressurized vessel as one which operates above 15 pounds per square inch gauge.

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Question 166

The boundary between wildland areas and residential growth has become known as a wildland urban interface.

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Question 167

All firefighting personnel with the potential for wildland response should seek formal training resulting in national wildfire coordinating group red card certification.

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Question 168

Fire can grow and spread rapidly through the upper portions of trees in what are known as crowning fires.

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Question 169

In hot and dry conditions, vegetation will have little moisture content and ignite easily, which will cause rapid fire growth even with low winds.

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Question 170

Weather and wind conditions should be assessed prior to initiating wildland fire suppression activities.

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Question 171

Weather, wind, fuel, and topography play a part in the blowup potential.

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Question 172

Flaring is a short lived, high intensity fire in a small area.

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Question 173

Flaring can cause spot fires and be a good indicator of the potential for a blowup.

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Question 174

The position of advanced warning devices should take into account several factors, such as weather, day/night, topography, and roadway speed.

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Question 175

A vapor suppressant can be applied to gasoline or diesel to reduce the risk of fire.

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Question 176

Apparatus and personnel should be downhill of the main body of fire as wildland fires move uphill faster than on flat terrain or downhill.

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