LEED AP Building Design and Construction (BD+C) Practice Exam

Where should CO2 sensors be installed to meet breathing zone requirements?

1. At floor level

2. 3 to 4 feet above the floor

3. Between 3 and 6 feet above the floor

4. Above 6 feet from the floor

The correct answer is: Between 3 and 6 feet above the floor

CO2 sensors should be installed between 3 and 6 feet above the floor to meet breathing zone requirements. This height range is particularly important because it aligns with the average breathing zone of occupants in a space, ensuring accurate detection of indoor air quality levels, specifically carbon dioxide concentration. Positioning the sensors in this zone allows them to effectively monitor air quality as it relates to human occupation and activity while minimizing the impact of variations in air stratification that can occur near the floor or higher up. By placing the sensors between 3 and 6 feet, they are more likely to capture the CO2 levels that occupants actually breathe, leading to better-informed decisions about ventilation rates and air quality management. This range is also consistent with guidelines provided by standards such as ASHRAE, ensuring that the installation adheres to established practices for promoting healthy indoor environments.