ASHRAE STD 62.1
Ventilation for Acceptable Indoor Air Quality
|Publication Date:||30 October 2020|
Unresolved objectors to Standard 62.1-2016 Addendum s noted that the definition for "unusual source" is unclear in distinguishing whether "rarely" refers to a source that is intermittent or transient within a space or if it is meant in the sense of commonality as in an object that would not be commonly found within in a space regardless of the duration of its presence. Addendum c clarifies what the committee considers an unusual source. The new definition makes clear that the unusual nature of a source has to do with its relationship to common items and activities within the space. For example, cooking is a common activity for a kitchen but would be an uncommon activity for a classroom; therefore a cooking classroom would have an unusual source if categorized as a classroom, meaning additional design considerations should be made in order to comply with the standard.
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.