No business or industrial use shall hereafter be maintained, established, altered, moved or expanded unless it complies with the performance standards set forth in this article. Continued conformance with such standards shall be a requirement for the continuance of any certificate of occupancy. Central utility systems serving three or more dwelling units, including but not limited to systems providing heat, water, air conditioning and electric power, shall be deemed to be nonresidential uses for the purposes of this article.