The design of the facilities are largely dependent upon the type of products manufactured and the potential for cross-contamination and microbiological contamination. For example, the facilities used for the manufacture of OTC oral products might not require the isolation that a steroid or sulfa product would require. Review the products manufactured and the procedures used by the firm for the isolation of processes to minimize contamination. Observe the addition of drug substance and powdered excipients to manufacturing vessels to determine if operations generate dust. Observe the systems and the efficiency of the dust removal system.
Some manufacturers recirculate air without adequate filtration.
This includes sanitary pumps, valves, flow meters and other equipment which can be easily sanitized. Ball valves, packing in pumps and pockets in flow meters have been identified as sources of contamination. In order to facilitate cleaning and sanitization, manufacturing and filling lines should be identified and detailed in drawings and SOPs. In some cases, long delivery lines between manufacturing areas and filling areas have been a source of contamination. Also, SOPs, particularly with regard to time limitations between batches and for cleaning have been found deficient in many manufacturers.