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A week ago
List and explain the 4 types of fire sensors (detectors) are commonly used in fire protection systems.
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Introduction to Security: Operations and Management
Edition: 5th
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Four types of fire sensors (detectors) are commonly used in fire protection systems. Thermal sensors provide the least amount of advanced warning time. It senses the heat in a protected area. Some thermal sensors are preset and respond at a specific temperature. Others, known as rate-of-rise sensors, respond to rapid increases in temperature. Infrared sensors respond to infrared light emissions in flame. Photoelectric sensors, detect smoke and particulates in the environment. Here, air enters a sensing chamber that measures changes in the amount of light emitted by the sensor. When the amount of light is restricted by smoke particulates, an alarm is activated. Ionization sensors, respond to invisible products of combustion, such as toxic gases. These "smoke detectors" are commonly used in residential settings. Here, particulates entering the sensor pass through two electrically charged plates that ionize the air. Smoke and other particulates entering the chamber change the electrical field, breaking the path of electricity between two metal plates (basically interrupting a circuit), which results in the sensor sounding an alarm. There are also flame detectors. As the name suggests, these types of sensors use infrared light wavelengths or ultraviolet radiation to detect the presence of light, which is created by the presence of flame.
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A week ago
Exactly what I needed for my project, TYSM
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