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Surface & Personnel Testing

Microbial sampling using a contact plate for surface monitoring

Surface and personnel testing are methods to collect, detect, and characterize the levels of various microorganisms to monitor the efficiency of disinfection routines in critical and non-critical manufacturing areas. Hygiene standards in a production environment are directly linked to the microbiological safety and quality of the finished products. To protect consumers, several government agencies have developed methods, including EU cGMP, U.S. FDA Aseptic Guidance, and USP <1116>, which apply to regulate industries like pharmaceutical, cosmetics, food, and beverages.

Traditional Surface Monitoring

To ensure the safety of a product, it is key to monitor the cleanliness of surfaces in the production area, such as tables, walls, or doors, and in isolators and cleanrooms. These surfaces and areas must be free of microorganisms to reduce the risk of cross-contamination, which could make the product unsafe for use or consumption.

Aseptic and controlled environments require frequent monitoring by surface sampling methods. Flat surfaces can be sampled by pressing contact plates or slides on the surface with uniform and steady pressure for a few seconds. The sample plates or slides are then incubated for the microorganisms to grow, before enumerating the grown bacteria cultures. The incubation conditions differ depending on microflora composition and regulatory requirements. Curved surfaces and hard-to-access areas can be monitored by the swab test method.


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Microbial personnel sampling in clean rooms and aseptic areas

Rapid Surface Monitoring

Manufacturers who require fast results can use rapid methods to quantify microbial residue post-sanitation and pre-operation. Such methods include colorimetric based assays requiring no instrument or sampling swabs requiring an instrument reader such as a luminometer. The need for rapid quality control methods is especially high in the food and beverages industry. Due to the perishable nature of their manufactured goods, but also in other industries to keep up with increasing production demand.

Personnel Monitoring

Personnel monitoring is performed to ensure the maintenance of the sterile environment. The majority of contamination within a facility can be traced to humans working in cleanrooms. Specific procedures for gowning, and sterilizing, need to be followed by the personnel before entering and exiting the aseptic cleanroom.