(a) The Commissioner shall establish by regulation the limitations of the levels, concentrations, or quantities of emissions of various air contaminants from any source necessary to protect the public health. Except as otherwise provided in or pursuant to this section, such levels, concentrations, or quantities shall be controlling throughout the United States Virgin Islands and no emission in excess thereof shall be lawful.
(b) In any area where the concentration of air pollution sources or of population, or where the nature of the economy or of land and its uses so require, the Commissioner may fix more stringent requirements governing the emission of air contaminants than those in effect pursuant to subsection (a) of this section.