Department of Engineering
BACHELOR OF SCIENCE IN CIVIL ENGINEERING
ENGINEERING UTILITIES 2
STUDY QUESTION 1-30
Alfred V. Matnog 01-13-2021
BSCE-3A
1. What three elements must exist for a combustion reaction (fire) to occur?
Ans.
The three elements are air, heat and fuel.
2. Described the difference between piloted ignition temperature and autoignition.
Ans.
The difference between the piloted ignition temperature and autoignition the piloted
ignition temperature of fuel is the temperature to start a fire by staring a flame or a spark that
activate combustion while autoignition temperature or the spontaneous ignition temperature it
is the lowest temperature which a certain combustible material will ignite without the use of
flame or spark.
3. Describe the Four stages of in the progression of a fire.
Ans.
Ignition, flame spread, flashover and consumption
1: Ignition- the three elements are needed the oxygen(air), heat and fuel with the right blend to
start the ignite.
2: Flame spread- the rapid range of fire to the closest combustible materials for example surface
of the wall, ceiling, floors and supporting timbers.
3: Flashover- when the combination of gases and air reach a critical portion the material ignites
in a great ball of fire.
4: Consumption- the burning sequence of the material itself turning it into ashes.
4. Describe the four classifications of fire type of fuel.
Ans.
Fires are classified into four groups by type of fuel:
Group A: Ordinary Combustibles (e.g., wood, paper, plastic, trash and so on)
Group B: Flammable Liquids (e.g., gasoline, oil, grease, acetone, and so on)
Group C: Electrical Equipment (e.g., any electrical wiring, connection, equipment, and so on)
Group D: Combustible Metals (e.g., potassium, sodium, aluminum, magnesium, and so on)
5. Describe the Five Types of building construction
Ans.
-Type I Fire-Resistive Construction
Fire-resistive Type construction. With its concrete and protected steel walls. floors, and
structural framework, was initially intended to confine a fire by its method Of construction that
is, by containing the fire With noncombustible wall, ceiling, and floor assemblies so it is confined
, to one floor or one space on a floor. However, fire does spread several floors in a modem fire-
resistive building through two paths: through duct-work in the central heating. ventilating, and
air conditioning (H VAC) system and by names extending vertically from Window to window.
-Type II Noncombustible Construction
Noncombustible (Type II) construction is also built of noncombustible steel or concrete walls,
floors. and structural framework; however, the roof covering is combustible. which can burn and
spread fire. The roof covering of a Type II building can be constructed of a combustible built-up
roof covering a layered asphalt and felt paper covering. or an ethylene propylene diene monomer
(EPDM) or polyvinylchloride (PVC) thermoplastic membrane. Combustible foams may be used as
thermal insulation. When a fire occurs inside a Type II building flames can rise to the underside of
the steel roof deck, conduct heat through the metal, and ignite the combustible roof covering. ne
asphalt paper. and foam insulation may burn and spread fire along the roof covering.
-Type III Ordinary Construction
It is built for non-combustible masonry-bearing walls, floors, structural framework, and roof
can be made of wood or another combustible material. The major recurring fire spread problem
with type III construction is concealed spaces and penetration. Are created by small voids. cavities.
and openings through which smoke and fire can spread are found behind the partition walls,
floors. and ceilings. Wood studs, floor joists, and suspended ceilings create concealed spaces.
Penetrations are created by small openings for utilities. These small openings around pipes and
Wires allow fire to spread into concealed spaces. Flames can spread vertically several stories or
horizontally to adjoining occupancies through concealed spaces. Fire spreads inside concealed
spaces of a Type Ill building by convection. the transfer of heat by motion of a liquid or gas. Heated
fire gases and flames in a concealed space can travel upwards several floors and break out in an
attic space. engulfing the entire building envelope.
-Type IV Heavy-Timber Construction
Heavy-limber (Type W) construction is built of a structure that consists of large timbers. In
this type of construction, a wood column cannot be less than 8 in thick in any dimension and a
wood beam cannot be less than 6 in thick. The floor and roof decking can be thick wood planks.
Exposed timber beams. Columns, and decks, if ignited in a fire, create large radiated heat waves
after the windows break during a blaze. If a fire in a heavy-timber building is not extinguished by
the initial firefighting attack, a tremendous fire with flames shooting out of the windows Will
spread fire to adjoining buildings by radiated heat. A fully involved type IV building requires large
water supply sources to protect nearby buildings.
-Type V Wood-Frame Construction
Wood-frame (Type V) construction is the most combustible of the five types of building
construction. A wood-frame building is the only one of the five types of construction that has
combustible exterior walls. The interior framing and exterior walls are typically constructed of
slender repetitive wood studs, Joists, rafters, and trusses that burn very rapidly. Flames can
spread out a window and then along the outside wood walls in addition to the interior fire spread.
A Type five building is rapidly engulfed in flame and is therefore reserved for small structures with
small occupancies.
BACHELOR OF SCIENCE IN CIVIL ENGINEERING
ENGINEERING UTILITIES 2
STUDY QUESTION 1-30
Alfred V. Matnog 01-13-2021
BSCE-3A
1. What three elements must exist for a combustion reaction (fire) to occur?
Ans.
The three elements are air, heat and fuel.
2. Described the difference between piloted ignition temperature and autoignition.
Ans.
The difference between the piloted ignition temperature and autoignition the piloted
ignition temperature of fuel is the temperature to start a fire by staring a flame or a spark that
activate combustion while autoignition temperature or the spontaneous ignition temperature it
is the lowest temperature which a certain combustible material will ignite without the use of
flame or spark.
3. Describe the Four stages of in the progression of a fire.
Ans.
Ignition, flame spread, flashover and consumption
1: Ignition- the three elements are needed the oxygen(air), heat and fuel with the right blend to
start the ignite.
2: Flame spread- the rapid range of fire to the closest combustible materials for example surface
of the wall, ceiling, floors and supporting timbers.
3: Flashover- when the combination of gases and air reach a critical portion the material ignites
in a great ball of fire.
4: Consumption- the burning sequence of the material itself turning it into ashes.
4. Describe the four classifications of fire type of fuel.
Ans.
Fires are classified into four groups by type of fuel:
Group A: Ordinary Combustibles (e.g., wood, paper, plastic, trash and so on)
Group B: Flammable Liquids (e.g., gasoline, oil, grease, acetone, and so on)
Group C: Electrical Equipment (e.g., any electrical wiring, connection, equipment, and so on)
Group D: Combustible Metals (e.g., potassium, sodium, aluminum, magnesium, and so on)
5. Describe the Five Types of building construction
Ans.
-Type I Fire-Resistive Construction
Fire-resistive Type construction. With its concrete and protected steel walls. floors, and
structural framework, was initially intended to confine a fire by its method Of construction that
is, by containing the fire With noncombustible wall, ceiling, and floor assemblies so it is confined
, to one floor or one space on a floor. However, fire does spread several floors in a modem fire-
resistive building through two paths: through duct-work in the central heating. ventilating, and
air conditioning (H VAC) system and by names extending vertically from Window to window.
-Type II Noncombustible Construction
Noncombustible (Type II) construction is also built of noncombustible steel or concrete walls,
floors. and structural framework; however, the roof covering is combustible. which can burn and
spread fire. The roof covering of a Type II building can be constructed of a combustible built-up
roof covering a layered asphalt and felt paper covering. or an ethylene propylene diene monomer
(EPDM) or polyvinylchloride (PVC) thermoplastic membrane. Combustible foams may be used as
thermal insulation. When a fire occurs inside a Type II building flames can rise to the underside of
the steel roof deck, conduct heat through the metal, and ignite the combustible roof covering. ne
asphalt paper. and foam insulation may burn and spread fire along the roof covering.
-Type III Ordinary Construction
It is built for non-combustible masonry-bearing walls, floors, structural framework, and roof
can be made of wood or another combustible material. The major recurring fire spread problem
with type III construction is concealed spaces and penetration. Are created by small voids. cavities.
and openings through which smoke and fire can spread are found behind the partition walls,
floors. and ceilings. Wood studs, floor joists, and suspended ceilings create concealed spaces.
Penetrations are created by small openings for utilities. These small openings around pipes and
Wires allow fire to spread into concealed spaces. Flames can spread vertically several stories or
horizontally to adjoining occupancies through concealed spaces. Fire spreads inside concealed
spaces of a Type Ill building by convection. the transfer of heat by motion of a liquid or gas. Heated
fire gases and flames in a concealed space can travel upwards several floors and break out in an
attic space. engulfing the entire building envelope.
-Type IV Heavy-Timber Construction
Heavy-limber (Type W) construction is built of a structure that consists of large timbers. In
this type of construction, a wood column cannot be less than 8 in thick in any dimension and a
wood beam cannot be less than 6 in thick. The floor and roof decking can be thick wood planks.
Exposed timber beams. Columns, and decks, if ignited in a fire, create large radiated heat waves
after the windows break during a blaze. If a fire in a heavy-timber building is not extinguished by
the initial firefighting attack, a tremendous fire with flames shooting out of the windows Will
spread fire to adjoining buildings by radiated heat. A fully involved type IV building requires large
water supply sources to protect nearby buildings.
-Type V Wood-Frame Construction
Wood-frame (Type V) construction is the most combustible of the five types of building
construction. A wood-frame building is the only one of the five types of construction that has
combustible exterior walls. The interior framing and exterior walls are typically constructed of
slender repetitive wood studs, Joists, rafters, and trusses that burn very rapidly. Flames can
spread out a window and then along the outside wood walls in addition to the interior fire spread.
A Type five building is rapidly engulfed in flame and is therefore reserved for small structures with
small occupancies.
