N.M. Code R. § 20.2.3.108
Ambient Air Quality Standards are not intended to provide a sharp dividing line between air of satisfactory quality and air of unsatisfactory quality. They are, however, numbers which represent objectives that will preserve our air resources. It is understood that at certain times, due to unusual meteorological conditions, these standards may be exceeded for short periods of time without the addition of specific pollutants into the atmosphere. The adoption of these statewide ambient air quality standards does not prohibit the promulgation of standards for specific areas, functions, and conditions within the state such as air sheds, municipalities, and certain counties, as authorized under the Act. As scientific data accumulates on the effects of a contaminant, these standards may be revised or additional standards added.
N.M. Code R. § 20.2.3.108