To limit the probability that an ignition source from adjacent buildings or facilities will ignite vapour from the pump, which could lead to a fire or explosion, which could lead to damage to the building or facility.
To limit the probability that vapour from the pump will accumulate on adjacent buildings or facilities, which could lead to ignition of the vapour from an ignition source on adjacent buildings or facilities, which could lead to a fire or explosion, which could lead to damage to adjacent buildings or facilities.