Abstract: A clean room includes walls, a floor and a ceiling which define the room. An air delivery system having a HEPA filter, a fan and an air return duct in communication with the filter, is provided to maintain the air in the room clean. A shield of the present invention is mounted in the room over a work surface to form a clean zone over at least a part of the table. The shield is mounted so that at least a part of the filter is within the clean zone so that filtered air will be forced into the clean zone. Accessories, such as an IV bar and a light panel may be provided with the shield to facilitate working in the clean zone. The shield creates a clean zone in the clean room having a higher class rating than the clean room rating without the use of additional HEPA filters and without the use of traditional laminar flow hoods.