Which device is described as a wire or tubing installed along the ceiling of large open spaces to detect heat increases?

• A. Smoke Detector
• B. Line Detector
• C. Audible Alarm
• D. Ceiling-Mounted Heat Detector

Answer: (B)

Linear heat detectors are designed for large, open spaces. They use a wire or hollow tubing laid along the ceiling to create a sensing line that covers a wide area. When heat along that line rises to a preset threshold (or the rate of rise indicates a fire), the detector triggers the alarm. This setup provides continuous coverage across long spans like warehouses or gyms, reducing dead zones that a single point detector might miss. Smoke detectors respond to smoke particles, not heat; a ceiling-mounted heat detector is a point sensor with heat detection at one spot; an audible alarm is only the sounding device, not the sensor itself.