__________ sensors project and detect an infrared beam across an area.
A) Photoelectric
B) Smoke
C) Air-aspirating
D) Thermal

Question

__________ sensors project and detect an infrared beam across an area.
A) Photoelectric
B) Smoke 
C) Air-aspirating
D) Thermal

Quizplus · Accepted Answer

Photoelectric sensors are designed to detect changes in light levels and can project an infrared beam across an area to detect any interruption in the beam. Smoke sensors are designed to detect the presence of smoke particles in the air, air-aspirating sensors sample the air in the area and analyze it for the presence of smoke or fire, and thermal sensors detect changes in temperature, which may indicate the presence of a fire but do not project a beam. Therefore, the best choice for detecting an infrared beam across an area would be photoelectric sensors.

__________ Sensors Project and Detect an Infrared Beam Across an Area