65.118—Alternative means of emission limitation: Enclosed-vented process units.
               		
               	 	
               	 	
               	 	               	 	               	 	               	 	               	 	
               	 	
    
        
        (a) Use of closed vent system and control device.
         Process units that are enclosed in such a manner that all emissions from equipment leaks are routed to a process or fuel gas system or collected and vented through a closed vent system to a control device meeting the requirements of  § 65.115 are exempt from the requirements of  §§ 65.106 through 65.114 and  § 65.116. The enclosure shall be maintained under a negative pressure at all times while the process unit is in operation to ensure that all emissions are routed to a control device.
     
    
        
        (b) Recordkeeping.
         Owners and operators choosing to comply with the requirements of this section shall maintain the following records:
     
    
        
        (1) 
         Identification of the process unit(s) and the regulated materials they handle.
     
    
        
        (2) 
         A schematic of the process unit, enclosure, and closed vent system.
     
    
        
        (3) 
         A description of the system used to create a negative pressure in the enclosure to ensure that all emissions are routed to the control device.