How do CO2 sensors contribute to IAQ-based ventilation control?

How do CO2 sensors contribute to IAQ-based ventilation control?

• A. Indicating occupancy and adjusting outdoor air accordingly
• B. Measuring water pressure
• C. Detecting humidity only
• D. Controlling electrical circuits

Answer: (A)

CO2 sensors are used to implement demand-controlled ventilation by using CO2 concentration as a real-time indicator of occupancy. When people are present, CO2 levels rise; the controller detects this and increases outdoor air flow to dilute the space, helping maintain good IAQ. If CO2 is low, ventilation can be reduced to save energy while still keeping air quality within acceptable limits. This makes CO2 sensors a practical proxy for adjusting ventilation based on actual use, rather than relying on fixed schedules. They don’t measure water pressure or humidity alone, and they aren’t devices that simply switch electrical circuits—they provide a signal that drives the ventilation system to modulate outdoor air.

CO2 sensors are used to implement demand-controlled ventilation by using CO2 concentration as a real-time indicator of occupancy. When people are present, CO2 levels rise; the controller detects this and increases outdoor air flow to dilute the space, helping maintain good IAQ. If CO2 is low, ventilation can be reduced to save energy while still keeping air quality within acceptable limits. This makes CO2 sensors a practical proxy for adjusting ventilation based on actual use, rather than relying on fixed schedules.

They don’t measure water pressure or humidity alone, and they aren’t devices that simply switch electrical circuits—they provide a signal that drives the ventilation system to modulate outdoor air.