This self-paced online course covers the operating principles of fire alarm system heat detectors. These are fire alarm initiating devices that detect either an abnormally high temperature or rate of temperature rise, or both, which would be indicative of a fire.

Upon completion you should be able to:

• Explain the differences between line and spot type heat detectors
• Explain the difference between restorable and non-restorable heat detectors
• Describe the operating principles of fixed temperature, rate-of-rise, and rate compensation types of heat detectors
• Explain how different types of heat detectors operate, including combination rate of rise and fixed temperature; line-type, wire; line-type, thermistor; line-type, pneumatic; bi-metallic; and eutectic salt
• Explain the advantages and disadvantages of heat detectors
• Describe "thermal lag" as it relates to heat detectors

Who Will Benefit

Anyone whose job involves designing, reviewing, evaluating or installing fire protection systems, including: designers, installers, engineers, electrical contractors, technicians, project managers, fire marshals, and architects

Course Summary

• Heat detectors are fire alarm initiating devices that detect either an abnormally high temperature or rate of temperature rise, or both, which would be indicative of a fire.
• Spot-type heat detectors are placed in one particular spot and can detect a fire only in that spot. Line-type heat detectors can detect a fire along the length of the detector.
• Restorable heat detectors can be reset after they are actuated provided the fire does not destroy them. Nonrestorable heat detectors must be replaced after they have been actuated.
• The advantages of heat detectors include:
  1. Low installation cost
  2. Low life cycle cost
  3. Stability
  4. Operation under varied environmental conditions
• The major disadvantage of heat detectors is that because they rely on heat from a fire to actuate, they are relatively slow to respond to a fire compared to other fire detectors.