MEP Fire Systems QUESTIONS AND ANSWERS 100%ACCURATE.
Factors affecting hazard fuel load: - ✅✅Occupancy and use conditions
Construction materials
Materials present within a building
Storage of items
Combustion is a - ✅✅chemical reaction involving
combustible materials and an oxidizing agent
producing heat or energy.
Fire is a - ✅✅chemical reaction producing energy in the
form of heat, light, and flame.
3 things that must be present in a fire - ✅✅Oxygen
Fuel
Heat
Diffusion flame - ✅✅Most natural flaming fires are diffusion fires.
Examples:
Lighting a match
Campfire
Structure fire
Smoldering - ✅✅No flame, but significant heat
Examples:
Charcoal on a grill
Cigarette burning in an ashtray
Spontaneous combustion/self-heating - ✅✅No known external source of heat
Oxidation occurs in an environment that limits heat
dissipation, so heat stays in the reaction.
Timing depends on the material and the environment.
Premixed flame - ✅✅Used to help people get ready for the day or for transportation
E.g. Cooking meals, driving to work, etc.
Gas fuel and air must mix before ignition or
combustion occur.
Knowing flammable limits of gas fuels helps safely
manage incidents.
, The incipient stage occurs
when - ✅✅heat, fuel, and oxygen come together and generate more heat than is dissipated.
Uninhibited chain reaction
No need for additional heat
sources (can self-sustain if
fuel/oxygen sufficient)
In the free burning stage - ✅✅adequate oxygen must be available to sustain the fire.
Fire growth is affected by
numerous factors:
Oxygensupply
Amount/type of fuel
Container size/structure
Insulation
The flashover stage - ✅✅is the transition in which room temperature reaches a point at which
all surfaces ignite.
Confined spaces:
determined by air supply
Outdoors: determined by
fuel supply
The smoldering/decay stage - ✅✅occurs when available fuel is exhausted or oxygen level
drops below 16%.
Burning only continues
as glowing combustion
or smoldering.
Conduction - ✅✅Transfer of heat from one body of material to another by direct contact
Convection - ✅✅Transfer of heat from one body of material to another via liquid or gas
Convection effect is influenced by size and shape of fire compartment.
Radiation - ✅✅Transfer of heat through electromagnetic energy such as light (indirect
contact)
Radiant heat travels in a straight line.
Affects the speed of flashover in structure fires
Can cause fires to spread
Cooling - ✅✅1 gallon of water absorbs 8000 Btu.
Water must be applied at sufficient rate and quantity.
Water cooling effectiveness depends on:
Fuel type
Form of material
Storage arrangement
Factors affecting hazard fuel load: - ✅✅Occupancy and use conditions
Construction materials
Materials present within a building
Storage of items
Combustion is a - ✅✅chemical reaction involving
combustible materials and an oxidizing agent
producing heat or energy.
Fire is a - ✅✅chemical reaction producing energy in the
form of heat, light, and flame.
3 things that must be present in a fire - ✅✅Oxygen
Fuel
Heat
Diffusion flame - ✅✅Most natural flaming fires are diffusion fires.
Examples:
Lighting a match
Campfire
Structure fire
Smoldering - ✅✅No flame, but significant heat
Examples:
Charcoal on a grill
Cigarette burning in an ashtray
Spontaneous combustion/self-heating - ✅✅No known external source of heat
Oxidation occurs in an environment that limits heat
dissipation, so heat stays in the reaction.
Timing depends on the material and the environment.
Premixed flame - ✅✅Used to help people get ready for the day or for transportation
E.g. Cooking meals, driving to work, etc.
Gas fuel and air must mix before ignition or
combustion occur.
Knowing flammable limits of gas fuels helps safely
manage incidents.
, The incipient stage occurs
when - ✅✅heat, fuel, and oxygen come together and generate more heat than is dissipated.
Uninhibited chain reaction
No need for additional heat
sources (can self-sustain if
fuel/oxygen sufficient)
In the free burning stage - ✅✅adequate oxygen must be available to sustain the fire.
Fire growth is affected by
numerous factors:
Oxygensupply
Amount/type of fuel
Container size/structure
Insulation
The flashover stage - ✅✅is the transition in which room temperature reaches a point at which
all surfaces ignite.
Confined spaces:
determined by air supply
Outdoors: determined by
fuel supply
The smoldering/decay stage - ✅✅occurs when available fuel is exhausted or oxygen level
drops below 16%.
Burning only continues
as glowing combustion
or smoldering.
Conduction - ✅✅Transfer of heat from one body of material to another by direct contact
Convection - ✅✅Transfer of heat from one body of material to another via liquid or gas
Convection effect is influenced by size and shape of fire compartment.
Radiation - ✅✅Transfer of heat through electromagnetic energy such as light (indirect
contact)
Radiant heat travels in a straight line.
Affects the speed of flashover in structure fires
Can cause fires to spread
Cooling - ✅✅1 gallon of water absorbs 8000 Btu.
Water must be applied at sufficient rate and quantity.
Water cooling effectiveness depends on:
Fuel type
Form of material
Storage arrangement
