To limit the probability that doors and their jambs will protrude an excessive distance into the width of corridors and other facilities, which could lead to persons contacting or colliding with the protrusions, which could lead to harm to persons.
To limit the probability that doors and their jambs will protrude an excessive distance into the width of exits, which could lead to an insufficient exit width to permit efficient egress in an emergency situation, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons.
To supersede the requirements of Sentence 9.9.3.2.(1) and Sentence 9.9.5.4.(1), which would otherwise prohibit obstructions in exits, and permit exit doors to cause a reduction in the width of exits, on the basis that the reduction in width is limited and should not negatively affect exit usage.