To limit the probability that vapours will migrate into other areas of a building, which could lead to the accumulation of the vapours in sufficient quantity to form an ignitable mixture, which could lead to the ignition of the vapours from a nearby ignition source, which could lead to harm to persons.
To limit the probability that vapours will accumulate in sufficient quantity to form an ignitable mixture, which could lead to the ignition of the vapours from a nearby ignition source, which could lead to harm to persons.