Visibility impairment

Visibility impairment or anthropogenic visibility impairment means any humanly perceptible difference due to air pollution from anthropogenic sources between actual visibility and natural visibility on one or more days. Because natural visibility can only be estimated or inferred, visibility impairment also is estimated or inferred rather than directly measured.


40 CFR § 51.301

Scoping language

For purposes of this subpart:

Is this correct? or