[Clause 5.3.1.4.(3)(a)] To limit the probability that dust will return into the atmosphere of the building, which could lead to an ignitable or hazardous accumulation of dust, which could lead to a fire or explosion, which could lead to harm to persons.
[Clause 5.3.1.4.(3)(b)] To limit the probability that a fire or explosion inside a dust collector will spread beyond the dust collector and inside the building, which could lead to harm to persons.
To permit exhaust air to return to the building if measures are taken that would limit the probability that ignitable concentrations of dusts will return into the building, which could lead to a fire or explosion in the dust collecting system, which could lead to harm to persons.