Which of the following heat transfer mechanisms requires no physical medium between the heat source and the receiving body, and operates via electromagnetic waves?
Fire Engineering Science
Question · Easy
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Short
Under the principles of fire science, what constitutes the fourth component of the fire tetrahedron, which distinguishes it from the fire triangle?
Which term describes the lowest temperature at which a liquid produces sufficient vapor to form an ignitable mixture with air near the surface, but will not sustain continuous combustion?
Question · Medium
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During a structure fire, a sudden and rapid transition occurs where all exposed combustible surfaces within a compartment are heated to their ignition temperature and ignite simultaneously. What is this phenomenon called?
If a gas at a constant temperature occupies a volume of 4.0 cubic meters at a pressure of 200 kPa, what will its volume be if the pressure is increased to 400 kPa under Boyle's Law?
Question · Hard
Which of the following describes the vapor density of a gas that will rise and disperse rapidly in ambient air under normal atmospheric conditions?
What is the term used to describe the heat absorption required to change a substance from a solid to a liquid state without changing its temperature?
In the chemistry of fire, what type of combustion occurs without a visible flame, characterized by slow oxidation on the surface of solid fuels?
Which of the following chemical reactions is defined by the absorption of thermal energy from the surroundings?
What is the primary firefighting agent mechanism of carbon dioxide (CO2) when applied to a Class B flammable liquid fire?
A mixture of flammable gas and air is exposed to an ignition source, but the combustion fails to propagate because the gas concentration is too rich. This means the gas concentration was above which limit?
Which of the following substances represents a gas with a vapor density significantly greater than air, meaning it will pool in basements and trenches?
Under the SANS standards for electricity safety, what is the mathematical expression of Ohm's Law, representing the relationship between Voltage (V), Current (I), and Resistance (R)?
When wood is heated, it undergoes chemical decomposition due to heat before combustion occurs, releasing flammable gases. What is this decomposition process called?
Which of the following conditions represents spontaneous combustion, where heat is generated within a material without an external heat source?
What is the term for the maximum temperature a fire can theoretically reach in a compartment under ideal conditions, assuming complete combustion and no heat loss?
What is the primary hazard associated with static electricity in industrial environments under fire engineering principles?
Which of the following gases is a toxic byproduct of incomplete combustion commonly found in fires, which binds to hemoglobin with an affinity 200 times greater than oxygen?
Under the Ideal Gas Law (PV = nRT), if the temperature of a gas in a rigid container (constant volume) is doubled, what happens to the pressure of the gas?
Which type of heat transfer occurs through the physical movement of currents in a fluid, such as hot smoke rising and travelling horizontally down a corridor?
What is the primary cause of friction loss when water flows through a fire hose?
Fire Service Hydraulics And Water Supply
If a fire pump is operating at an elevation where it needs to pump water uphill to a nozzle located 30 meters above the pump, what is the pressure loss due to elevation alone?
What dangerous hydraulic phenomenon occurs when the flow of water through a hose or pipe is stopped suddenly, creating a high-pressure shockwave?
Under SANS 1128, which type of fire hydrant is commonly installed below ground level in South Africa, requiring a standpipe to be connected for operation?
How does doubling the diameter of a fire hose affect the friction loss inside the hose at a constant flow rate?
What is the recommended operating pressure (nozzle pressure) for a standard handline smooth-bore nozzle to produce an effective solid fire stream?
Which pump term refers to the creation of a partial vacuum in the pump casing and suction hose to lift water from a static source below the pump?
A centrifugal fire pump is drafting water from a static source. What is the theoretical maximum height that water can be lifted by atmospheric pressure at sea level under a perfect vacuum?
Which type of pump is primarily used as a fire service vehicle main pump because it can move large volumes of water and utilize pressure from hydrants?
If a water reticulation system has a static pressure of 600 kPa and the pressure drops to 400 kPa when a hydrant is opened, what is the remaining pressure in the system during flow called?
Under hydraulic principles, if the flow rate (litres per minute) through a fire hose is doubled, what happens to the friction loss?
What does the term 'head of water' refer to in water supply calculations?
When drafting water, what is the purpose of placing a strainer on the intake end of the hard suction hose?
What is the primary function of a fire pump's pressure governor or relief valve during operations?
Which of the following describes a water main configuration that provides the most reliable flow and pressure for fire hydrants by eliminating dead ends?
If a pressure gauge on a hydrant reads 450 kPa under static conditions, and drops to 420 kPa when a fire engine begins pumping, what does this 30 kPa drop indicate?
What is the primary hydraulic benefit of using a nozzle with a built-in fog pattern compared to a smooth-bore nozzle?
When calculating pump discharge pressure (PDP), which of the following variables must be included?
What is the effect of pump cavitation on fire service operations?
Which of the following is the standard unit of measurement for water flow rates in South African municipal water supply and fire service calculations?
Under SANS 10400 Part T, what does a fire resistance rating of '120/60/60' for a building element represent?
Building Construction And Fire Safety
What is the primary purpose of compartmentation in building design under fire safety regulations?
Which type of building construction is characterized by structural elements made of non-combustible materials (like steel and concrete) that have no fire-resistant coatings or protection?
Under SANS 10400-T, what is the maximum travel distance allowed to the nearest exit or protected escape route in a building without an automatic sprinkler system?
What is the primary fire hazard associated with unprotected structural steel members in a commercial building?
How does solid heavy timber behave in a fire, compared to lightweight wood trusses?
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