Ingersoll Rand Air Solutions, Davidson, NC, has announced that it is the first manufacturer in the world to be certified Class 0 for centrifugal air compressors. Concurrently, Ingersoll Rand has received Class 0 certification in their oil-free rotary screw line of compressors. The certifications were granted to the entire range of air-cooled and water-cooled oil-free rotary screw compressors (37 to 350 kW) and water-cooled, oil-free centrifugal air compressors (160 to 5,000 kW) by TÃœV Rheinland, an independent testing and assessment agency. The most stringent of all ISO 8573.1 classifications, Class 0 certification was added in 2001 in response to critical applications where air purity is essential such as the pharmaceutical, food and beverage, and textiles industries. The certification recognizes compressors that discharge air free of added oil aerosols, vapors, and liquids.