High-Rise Building Construction and Compartmentalization Flashcards

Under NYC Local Law 5 of 1973, non-sprinklered office floors could meet compartmentation requirements by dividing space into areas no larger than:

Answer: 7,500 sq ft

Local Law 5 allowed compartments of up to 7,500 sq ft enclosed by fire-rated construction as an alternative to sprinklers.

Which NYC law required all office buildings 100 feet or taller to be fully sprinklered by July 1, 2019?

Answer: Local Law 26 of 2004

Local Law 26 of 2004, passed after 9/11, required full sprinkler protection in high-rise office buildings by 2019.

What is the main purpose of firestopping a 'poke-through' in a floor slab?

Answer: To stop fire and smoke from moving between floors through the opening

Poke-throughs are utility holes through the slab and must be sealed so fire and smoke cannot travel vertically.

In a curtain-wall high-rise, the gap between the floor slab edge and the exterior wall can allow fire to:

Answer: Spread vertically to the floor above

An unsealed slab-edge gap lets flames and smoke travel up to the next floor, so it must be filled with perimeter fire safing.

A fire damper in an HVAC duct that passes through a fire-rated wall usually closes when:

Answer: A fusible link melts from heat

Fire dampers are held open by a fusible link that melts at a set temperature, letting the damper close.

How does a smoke damper differ from a standard fire damper?

Answer: It is triggered by smoke detection rather than only by heat

Smoke dampers close on a signal from smoke detectors or the fire alarm system to limit smoke movement through ducts.

In center-core high-rise construction, the core typically contains:

Answer: Elevators, stairs, and utility shafts

Center-core design groups elevators, stairs, restrooms, and vertical shafts in the middle of the floor plate.