Clean areas nowadays are advanced technology solutions with very high standard and criteria applied on air quality level. Egyptian Radioisotopes Production facility (RPF) is a facility that requires clean area to produce technetium (Tc99m) isotope for medical purposes. The air cleanliness inside area is dependent on the air quality of supplied air, contaminant and pollutant sources, dedicated ventilation system in addition to rigorous precautions to sterilize space of the area and commitment to follow standard recommendations. Two main standard classes are available in production area, A and C according to ISO 14644-1. Our paper deals with class C in which isotope is produced and some tests are conducted to know particle counts in that area in addition to prediction of these counts by computer simulation Contam-CFD0 program, which predicts transient particles count behavior which compared with standard WHO values and measurements for validation. Biological tests are also implemented to monitor sterility of area to confirm cleanliness and validity for processing medical radioisotope. High efficiency particulate air filters with class H14 are dedicated for the clean area and equipped with pressure drop manometer for replacement in case of blockage. Simulation program is also used to predict particles concentration in case of filter contamination.