Appendix E Clean air delivery and monitoring
Section E101 General
E101.1 Demand control ventilation.
Group A, B, E and I occupancies shall be equipped with a minimum of one carbon dioxide sensor for every 500 square feet (46 m2) of occupiable space. Carbon dioxide sensors installed in accordance with this section shall meet the requirements in Sections E101.1.1 and E101.1.3. Mechanical equipment serving each zone shall be equipped with controls that meet the requirements in Section E101.1.2.
Exception: Occupiable zones less than 500 square feet (46 m2).
E101.1.1 Carbon dioxide sensor performance specifications.
Each carbon dioxide sensor installed in accordance with Section E101.1 shall meet the following carbon dioxide measurement specifications as certified by the equipment manufacturer:
- 1.
Range lower bound less than or equal to 400 parts per million.
- 2.
Range upper bound greater than or equal to 2,000 parts per million.
- 3.
Accuracy within ±75 parts per million at a reading of 1,000 parts per million.
- 4.
Output resolution less than or equal to 20 parts per million.
E101.1.2 Mechanical system controls.
Controls for the mechanical equipment installed in accordance with Section E101 shall:
- 1.
Receive data from the carbon dioxide sensor in the occupiable zone(s) at least once per 5 minutes.
- 2.
Be calibrated to provide pre-established outdoor airflow rates, or be equipped with the necessary instrumentation to measure the outdoor airflow rate.
- 3.
Be capable of adjusting the outdoor airflow rate in response to an adjustable outdoor airflow setpoint.
- 4.
Increase the amount of outdoor air provided to each occupiable zone until the carbon dioxide level in each occupiable zone falls below a maximum threshold as defined by the user.
E101.1.3 Carbon dioxide detection threshold level.
The default detection threshold level for carbon dioxide measurement above which triggers an alert in accordance with Section E101.1.4 shall be set to 1,100 parts per million. The end user can modify the detection threshold level based on specific operations and needs.
E101.1.4 Carbon dioxide detection threshold level exceeded.
When carbon dioxide levels exceed the detection threshold level established in Section E101.1.3, the mechanical equipment shall modify the outdoor airflow rate as required in Section E101.1.2. When the carbon dioxide concentration remains above the detection threshold level for a period of 30 minutes or more, the occupants in the zone shall be alerted by approved audible and visual notification devices or through a building monitoring system.