To exempt certain ducts from the requirements of Sentence 184.108.40.206.(1), which would otherwise require fire dampers to
be installed, on the basis that:
- the lack of dampers in this case will not contribute
significantly to the spread of fire,
- accidental closing of the dampers by the cooking operations
would cause an undue hardship to the operations, and
- the fire dampers and their operating parts could collect
grease, be very difficult to clean, and add to the fire hazard.