Whenever the commission determines that emissions from one or more air contaminant sources are causing localized imminent danger to human health or safety, but that there is not a generalized condition of air pollution of the type referred to in the Texas Water Code, §5.514, the commission shall order the person or persons responsible for the emissions to reduce or discontinue the emissions immediately. In such event, the notice and hearing requirements of §118.4 of this title (relating to Hearings) shall apply.