Practical Techniques of Preloading Culture Medium Plate with Finished Products

      

　　Requirements for microorganisms at all levels of clean areas

　　Dynamic monitoring of microorganisms should be carried out to assess the microbial status of aseptic production. Monitoring methods include sedimentation method, quantitative airplankton sampling method, and surface sampling method (such as cotton swab wiping method and contact dish method). Dynamic sampling should avoid adverse effects on clean areas.

　　Monitoring of surfaces and operators should be carried out after critical operations are completed. In addition to normal production operation monitoring, microbial monitoring can be added after system validation, cleaning or disinfection operations are completed.

　　Note:

　　(1) All values in the table are averages.

　　(2) The exposure time of a single settling dish can be less than 4 hours, and multiple settling dishes can be continuously monitored and counted at the same location.

　　Clean areas are classified by state

　　Dynamic refers to the state in which production equipment operates according to a predetermined process mode and has a specified number of operators operating on site.

　　Static refers to a state in which all production equipment is installed, but there is no production activity and no operator present.

　　Clean areas are classified according to airflow patterns

　　The air flow organization in the clean area is used to achieve a specific air cleanliness level in the production clean area to limit and avoid the contamination of dust particles and bacteria attached to dust particles to products, packaging materials, equipment, containers, and utensils that directly contact products.

　　Indoor air organization according to the flow state of laminar flow and turbulence, laminar flow is divided into vertical unidirectional flow (laminar flow) and horizontal unidirectional flow (laminar flow).

　　Unidirectional flow refers to the flow of air in the same direction, in a stable and uniform manner and at a sufficient rate. Unidirectional flow continuously removes particles from critical operating areas, as shown below:

　　Vertical unidirectional flow clean area:

　　Vertical unidirectional flow controls pollution in all directions at a suitable airflow speed. The faster the air flow, the better the cleaning effect. Usually, in the design of a unidirectional flow clean room, the A-level vertical unidirectional flow inner section custom v ≥ 0.36m/s.

　　The most common vertical unidirectional flow device in daily production is the A-class laminar flow hood, which is small in size and is mainly used to protect high-risk areas of product production, such as the opening area of the inner packaging material for aseptic filling and the preservation of sterilized utensils.

　　Horizontal unidirectional flow clean area: The horizontal unidirectional flow clean area is covered with high-efficiency filters on the side air supply wall, and the opposite return air wall is covered with medium-efficiency filters (or combined with the return style column). The airflow reaches a clean state through the high-efficiency air filter, and flows through the working area at a uniform speed in the horizontal direction in the horizontal unidirectional flow state, taking away the dust particles, residual heat and residual humidity emitted by the working area, and enters the return air static pressure box through the return air. The most common horizontal unidirectional flow device in daily production is the horizontal purification workbench, with a small specification.

　　The horizontal unidirectional flow clean room must consider overcoming the influence of the gravity sedimentation of dust particles. Therefore, the design of the A-level horizontal unidirectional flow clean room section customs should be slightly larger than the vertical unidirectional flow clean room wind speed.