Microbiological Monitoring of Clean Rooms and Environmental Control in a Pharmaceutical Company in Sagamu, Ogun State

Clean room environmental monitoring is a regulatory requirement for pharmaceutical manufacturers producing sterile and non-sterile products under GMP conditions. This study assessed the microbiological monitoring program of clean rooms in a medium-scale pharmaceutical company in Sagamu, Ogun State, South West Nigeria, against international GMP requirements and EU Annex 1 standards. A 12-month retrospective review of environmental monitoring records was conducted, supplemented by prospective settle plate, contact plate, and active air sampling over two production quarters. Isolate characterization from out-of-specification results was performed by morphological and biochemical methods. Trend analysis of environmental data using control charts was applied to evaluate monitoring program effectiveness. Results showed that Grade C clean room environments experienced out-of-specification events in 14.6 percent of monitoring sessions, exceeding the facility's internal action limit of 10 percent. The predominant environmental contaminants were Bacillus species (41%), coagulase-negative Staphylococci (33%), and Penicillium species (18%). Root cause analysis identified air handling unit filter degradation and personnel gowning non-compliance as primary corrective action targets. Following remediation, out-of-specification rates declined to 6.2 percent within three months. These findings demonstrate the value of trend analysis and corrective action frameworks in clean room management and provide a practical operational model for environmental monitoring optimization in Nigerian pharmaceutical manufacturing. Keywords: clean room, environmental monitoring, GMP, pharmaceutical manufacturing, Sagamu.