S95 Initiating Devices 3

Question 1

A fixed-temperature heat detector activates when the ambient temperature at the device reaches a predetermined level. What is the most common fixed-temperature rating for standard applications?

Accepted Answer

135°F (57°C)

Answer

The most common fixed-temperature rating for standard environments is 135°F (57°C), which is low enough to detect abnormal heat while remaining above typical ambient temperatures.

Question 2

A rate-of-rise heat detector triggers an alarm when the temperature increases by more than how many degrees Fahrenheit per minute?

Accepted Answer

25°F per minute

Answer

Rate-of-rise detectors are designed to alarm when temperature increases at a rate exceeding approximately 12–15°F per minute, indicating a rapidly developing fire condition.

Question 3

Which type of heat detector is MOST appropriate for an environment where slow-smoldering fires are expected but ambient temperatures may already be high?

Accepted Answer

Fixed-temperature detector at a higher rating

Answer

In high-ambient-temperature environments, a fixed-temperature detector set at an appropriately higher rating ensures the detector does not false-alarm while still responding to an actual fire.

Question 4

After activation, which type of heat detector must be replaced rather than reset?

Accepted Answer

Fusible-link or fusible-alloy fixed-temperature detector

Answer

Fusible-link or fusible-alloy detectors operate by melting an alloy at a set temperature; once activated, the element is destroyed and the entire detector must be replaced.

Question 5

A manual pull station must be installed at what height above the finished floor per NFPA 72?

Accepted Answer

Between 42 and 54 inches

Answer

NFPA 72 requires manual pull stations to be mounted with the operable part between 42 inches (3.5 ft) and 54 inches (4.5 ft) above the finished floor.

(S95) Supervision of Fire Alarm System Practice Test

(S95) Supervision of Fire Alarm System Practice Test

S95 Initiating Devices 3