Chapter 3 - Smoke Management Systems Flashcards
- System that limits the exposure of building occupants to smoke. May include a combination of compartmentation, control of smoke migration from the affected area, and a means of removing smoke to the exterior of the building.
Smoke Management System
p 57
- Engineered system designed to control smoke by the use of mechanical fans to produce airflows and pressure differences across smoke barriers to limit and direct smoke movement.
Smoke Control System
p 57
Presently, smoke management systems are subject of two different NFPA standards ?
NFPA 92A, Standard for Smoke-Control Systems Utilizing Barriers and Pressure Differences
NFPA 92B, Standard for Smoke Management Systems in Malls, Atria, and Large Spaces
p 57
The _______ ________ is a naturally occurring vertical movement of air within a building.
Stack effect
p 59
- Formation of smoke into layers as a result of differences in density with respect to height with low density layers on the top and high density layers on the bottom.
Stratification
p 59
- Phenomenon of a strong air draft moving from ground level to the roof level of a building. Affected by height, configuration, and temperature differences between inside and outside air.
Stack Effect
p 59
When the outside air is cooler than the buildings interior, air will move ?
upward through the building
p 59
A _____________ flow of air can occur during warmer weather when the air inside is cooler than the air outside.
downward
p 59
During very ______ weather conditions, the stack effect causes air to move vertically downward in buildings. This is referred to as ___________ or __________ stack effect.
hot / negative / reverse
p 59
Smoke stratification and movement occurs in part due to the smoke’s _____________. This _____________ is the result of a reduced density and from expansion.
buoyancy / buoyancy
p 59
Wind acts to promote ____________, rather than ____________, air movement through the building. This spreads smoke from the ____________ side to the ____________ side of the building.
horizontal / vertical / windward / leeward
p 60
When a fire starts, an operating _______ system can transport smoke to every area that the system serves.
HVAC
p 60
- Thermal or chemical decomposition of fuel (matter) because of heat that generally results in the lowered ignition temperature of the material.
Pyrolysis
p 62
The materials that compose smoke vary from fuel to fuel, but generally all smoke is ?
toxic
p 62
This is a byproduct of the incomplete combustion of organic (carbon-containing) materials and is probably the most common product of combustion encountered in structure fires ?
Carbon monoxide
p 62
This gas is produced in the combustion of materials containing nitrogen and is a significant byproduct of polyurethane foam (commonly used in furniture and bedding). It is also commonly encountered in smoke, although at lower concentrations than CO ?
Hydrogen cyanide (HCN)
p 62
This is a product of complete combustion of organic materials and is not toxic in the same manner as CO and HCN. It acts as a simple asphyxiant by displacing oxygen. It also acts as a respiratory stimulant by increasing the respiratory rate ?
Carbon dioxide (CO2)
p 62
The purpose of a _________ ______________ system is to reduce occupant deaths and injuries and to aid in the safety of firefighters by removing and controlling the spread of smoke.
smoke management
p 63
_____________ smoke control systems are those that are intended and specifically listed for smoke control purposes.
Dedicated
p 64
________________ smoke control systems are those that share components with other systems such as the buildings HVAC system.
Nondedicated
p 65
- Smoke control strategies that incorporate fixed components that provide against the spread of smoke and fire. These smoke control components include fire doors, fire walls, fire stopping or barrier penetrations and stair and elevator vestibules.
Passive smoke control
p 66
Codes such as NFPA ______, Life Safety Code provide criteria for the construction of smoke barriers, including doors and smoke dampers.
NFPA 101
p 66
There are two types of pressurization systems: ?
positive pressure systems and negative pressure systems
p 66
These systems supply air to the zones adjacent to the zone of the fires origin ?
Positive-pressure
p 66
