(a) A design must include sufficient ventilation to eliminate an accumulation of fumes or gases at a level that could adversely impact human health, safety, welfare, or the environment.     
      (b) An enclosed area that is accessible to individuals must have automatic mechanical ventilation. Automatic mechanical ventilation consists of:      
        (1) a continuous ventilation system that provides at least one complete air exchange every 10 minutes; or       
        (2) an intermittent ventilation system that provides at least one complete air exchange every two minutes.       
      (c) A sludge processing unit must prevent nuisance odors.     
     Source Note:        The provisions of this §217.246 adopted to be effective August 28, 2008, 33 TexReg 6843; amended to be effective December 4, 2015, 40 TexReg 8254