To limit the probability that interior ceiling finishes that have an inappropriately high flame-spread property will be used in certain building locations, which could lead to the spread of fire across the exposed surfaces of the finishes, which could lead to harm to persons.
To exempt interior ceiling finishes used in certain locations from the application of Sentence 3.1.13.2.(1), which would otherwise permit higher flame-spread ratings, on the basis that a lower flame-spread rating is needed in these locations to protect persons during evacuation.