310204k Fire And Smoke Detection

Question 1

Name the organization that publishes the standards and specifications for fire detection equipment.

Answer 1

The Underwriters Laboratories of Canada (ULC)

Question 2

The changes to the immediate environment by a fire is called:

Answer 2

Is called the fire signature

Question 3

List the 4 phases of a fire

Answer 3

1. Incipient
2. Smouldering
3. Flames
4. Intense heat

Question 4

Name the three functions of a fire and smoke detection system

Answer 4

1. Detection
2. Annunciation
3. Protective measures

Question 5

Why are ionization and optical smoke detectors sometimes combined?

Answer 5

Ionization is best for detecting particles smaller than 0.3 μm and photo detection is best for detecting particles larger than 0.3 μm
Combining them allows for the detection of a wider range of particle sizes.

Question 6

What type of smoke detection system is suitable for detecting arcing in wires or overheating wire insulation?

Answer 6

Cloud chamber detectors

Question 7

Where can you get the calibration specifications for smoke detectors?

Answer 7

The Canadian Fire Alarm Association
The manufacturer

Question 8

Name the two methods of spot smoke detector testing

Answer 8

1. Single head testing
2. System testing

Question 9

If a smoke detector tests out of specification, what procedure should the technician follow?

Answer 9

Clean, retest, and replace detectors if necessary

Question 10

How is optical flame detector sensitivity determined?

Answer 10

By testing against a reference flame size for a given fuel type

Question 11

What is the mathematical relationship between flame size and flame detector distance?

Answer 11

Doubling the detection distance results in 25% of the radiant energy reaching the detector

Question 12

Name three common optical flame detector designs

Answer 12

1. Infrared (IR)
2. Ultraviolet (UV)
3. UV/IR Combination detectors

Question 13

At what wavelength does CO2 emission occur?

Answer 13

4.4 μm

Question 14

Name three basic types of heat detectors

Answer 14

1. Fixed temperature
2. Rate of rise
3. Rate of anticipation

Question 15

What are the three main categories of flame detectors?

Answer 15

1. Optical
2. Video
3. Heat detectors

Question 16

What are the five common smoke detection methods?

Answer 16

1. Ionization
2. Light obscuration
3. Photoelectric light scattering
4. Cloud chamber
5. Laser particle counter

Question 17

Which type of smoke detector contains a small amount of radioactive material?

Answer 17

An ionization smoke detector

Question 18

What type of smoke detectors are designed to be incorporated into an air aspiration system?

Answer 18

Laser smoke particle counter