To exempt openings in fire separations used in manufacturing operations [e.g. openings used for the flow of material from storey to storey] from the requirements of Sentence 3.2.8.1.(1) and Articles 3.2.8.3. to 3.2.8.9., which would otherwise require a vertical fire separation or certain fire protection measures, if equivalent fire protection is provided to compensate for the lack of closure.
This is to limit the probability that fire will spread through the openings to other parts of the building, which could lead to damage to the building.