In one embodiment, an air filtration system includes a first ventilation path connected between at least one external air supply and a clean room. The first ventilation path is configured to direct air from the at least one external air supply to the clean room. A second ventilation path is connected to the clean room. The second ventilation path is configured to recirculate air in the clean room. A third ventilation path, separate from the first path, is connected between the at least one external air supply and a tool environment disposed within the clean room. The third ventilation path includes an ultra-pure air filtration unit disposed between the outdoor air supply and the tool environment. The ultra-pure air filtration unit includes a compressor and a dryer.