Technical Booklet K Ventilation·Page 28·2.32
Override facility for automatic controls
Automatic ventilation controls should have a manual override to allow occupants to turn extraction on when needed.
Any automatic control should have an override facility to allow the occupant to turn the extract on manually.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/Technical Booklet K - Ventilation.pdf