Fire protection systems

Question 1

briefly describe the components of a thermal switch fire detection system

Answer 1

temperature sensitive switches that complete a circuit at a specific temperature and trigger a warning

Question 2

Are thermal switches wired in series or in parallel with each other?

Answer 2

Parallel

Question 3

How are the detector units in a double-loop Fenwal system wired?

Answer 3

in parallel between two complete loops of wiring

Question 4

In what way is a thermocouple fire warning system different from a thermal switch system?

Answer 4

Thermocouple systems are sensitive to the rate of temperature change, whereas thermal switch system respond to a specific temperature value.

Question 5

Briefly describe the components of a KIDDE continuous loop fire detection system

Answer 5

A KIDDE system has an iconel loop whose resistance changes with temperature

Question 6

briefly describe the components and operation of a Lindberg fire detection system

Answer 6

A stainless steel tube contains an inert gas and a discrete material that absorbs some of the gas. When the tube heats up, some gas is released, raising the pressure in the tube, which activates a pressure switch.

Question 7

describe the process or mechanism by which a photoelectric smoke detector generates a warning of a possible fire.

Answer 7

Smoke particles refract light in the detector unit causing the photelectric cell to conduct electricity and trigger the alarm.

Question 8

How can the operation of photelectric smoke detector be tested?

Answer 8

by actuating a test switch

Question 9

Name two types of smoke detection system used in aircraft

Answer 9

Light refraction (photoelectric) types and ionization types

Question 10

What are the usual locations where a carbon monoxide detector would be installed?

Answer 10

in an aircraft cockpit or cabin

Question 11

How does a carbon monoxide detector indicate the presence of this deadly gas?

Answer 11

The tan spot on the detector turns gray or black

Question 12

What are the possible effects of kinks and sharp bends in the sensing element(s) of a fire warning system?

Answer 12

False fire warnings caused by short circuits

Question 13

How is a Freon container checked for proper pressure?

Answer 13

A chart must be used to determine the maximum and minimum gauge pressure readings based on the ambient temperature.

Question 14

Name the two basic types of fire extinguishing systems

Answer 14

Conventional system

High-rate discharge system

Question 15

Name the extinguishing agent most commonly used by conventional fire extinguishing systems

Answer 15

CO2

Question 16

Name the extinguishing agent most commonly used by high-rate discharge fire extinguishing system

Answer 16

Halon,

Question 17

How are freon bottles protected from excessively high temperature and how can you tell that this has occurred

Answer 17

A thermal fuse (blowout disk) will release the agent if the bottle temperature exceeds a certain limit. This blows out a red indicator disk

Question 18

What condition is indicated if the yellow disk is missing in a fire extinguishing system?

Answer 18

Discharged normally

Question 19

Describe the mechanism by which a freon bottle is discharged

Answer 19

An electrical signal fires an explosive squib, which ruptures a frangible disk

Question 20

How is the service life of a discharge cartridges calculated?

Answer 20

From the date stamped on the cartridge by the manufacturer.