Cleanroom microflora are of importance for microbiologists and quality control personnel in order to assess changes in trends. Shifts in the types of microflora may indicate deviations from the "norm" such as resistant strains or problems with cleaning practices. Given the few published studies of the typical microflora, this paper uniquely reviews over 9000 microbial isolates from a range of different grades of cleanroom. The paper concludes that the typical flora are primarily those associated with human skin (Gram-positive cocci), although microorganisms from other sources such as the environment (Gram-positive rods) and water (Gram-negative rods) are also detected, although in lower numbers.
Lay abstract: It is of importance that pharmaceutical manufacturers and healthcare pharmacies review the types and numbers of microorganisms found within their clean areas. Such examination should be carried out over a long period of time so that the complete picture can be revealed. This is important in order to understand if certain species are being recovered pose a product or environmental risk and to check if the cleaning and sanitization practices are effective.