Intent 1:
To exempt certain branch ducts from the requirements
of Sentence 9.10.13.13.(1), which would otherwise require fire
dampers to be installed, on the basis that:
- the ducts are small,
- the ducts are capable of withstanding high temperatures,
- it is unlikely that hot gases will contact combustible
building components, and
- the lack of dampers in this case will not contribute
significantly to the spread of fire.