S95 Initiating Devices 2

Question 1

Which type of smoke detector uses a small amount of radioactive material to ionize air and detect combustion particles?

Accepted Answer

Ionization detector

Answer

Photoelectric detector

Answer

Projected beam detector

Answer

Aspirating smoke detector

Question 2

A photoelectric smoke detector is MOST effective at detecting which type of fire?

Accepted Answer

Slow smoldering fires that produce large smoke particles

Answer

Fast-flaming fires with little smoke

Answer

Fires producing invisible combustion gases

Answer

Fires producing extreme radiant heat

Question 3

What is the maximum spacing between smoke detectors on a smooth, flat ceiling as specified by NFPA 72?

Accepted Answer

50 feet

Answer

20 feet

Answer

30 feet

Answer

70 feet

Question 4

A projected beam smoke detector consists of which two primary components?

Accepted Answer

Transmitter and receiver

Answer

Sensor and relay module

Answer

Ionization chamber and sampling tube

Answer

Aspirator and filter assembly

Question 5

Where are duct smoke detectors required to be installed according to NFPA 72 and NFPA 90A?

Accepted Answer

In HVAC ducts to detect smoke and shut down air handling units

Answer

Only at return air registers

Answer

Adjacent to sprinkler heads in mechanical rooms

Answer

At every branch duct above 12 inches in diameter

Question 6

Which condition would cause a spot-type smoke detector to generate a nuisance alarm?

Accepted Answer

Steam or high humidity near the detector

Answer

High ambient temperature above 100°F

Answer

Low ambient light levels in the room

Answer

Reduced building occupancy at night

Question 7

An aspirating smoke detection (ASD) system draws air samples through a pipe network to a central detection unit. What is a primary advantage of this design?

Accepted Answer

Ability to detect extremely low concentrations of smoke at very early stages

Answer

Lower installation cost than spot detectors

Answer

Simpler maintenance with fewer parts

Answer

Higher alarm threshold to reduce nuisance alarms