ASHRAE STD 62.2
Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings
|Publication Date:||23 January 2016|
The intent of Section 7.2.2, "Demand-Controlled Local Exhaust Fans," is to require fans to have at least one speed setting meeting the minimum required exhaust airflow rate where the corresponding sone rating is 3 or less. This change clarifies this intent. Currently, the language in this section would permit any fan with a high speed setting exceeding 400 cfm to be exempt from the sone requirement, even if operating on a lower speed setting. For example, a kitchen range hood with speed settings of 100, 200, and 401 cfm is currently not required to meet the sone requirements at any of these settings. Closing this loop hole will ensure that occupants that have typical-sized range hoods (i.e., those with at least one speed setting ≤400 cfm) will have at least one speed setting rated ≤3 sone.
Note: In this addendum, changes to the current standard are indicated in the text by underlining (for additions) and (for deletions) unless the instructions specifically mention some other means of indicating the changes.