In pharmaceutical, food and other industries, weighing problems will be encountered, and equipment such as negative pressure weighing cover will often be used. If there is a clean level requirement in the preparation weighing room, the wind speed shall be controlled according to the corresponding clean level. If there is no clean level requirement, the wind speed shall be strictly evaluated to control the corresponding wind speed, so as not to cause cross contamination caused by the dispersion of reagents.

The specific requirements for the use of the negative pressure weighing cover are related to the cleanliness level of the weighing room. If the weighed materials require a sterile environment, it needs to be A-level weighing cover under the B-level background. The wind speed requirement is 0.36-0.54m/s. According to Article 9 of GMP for the production of sterile drugs, the high-risk operation areas, such as the filling area, the area where the rubber stopper barrel is placed and the open packaging container directly in contact with the sterile preparation, and the area for aseptic assembly or connection operation, The one-way flow console (cover) shall be used to maintain the environmental state of the area. The unidirectional flow system must supply air uniformly in its working area, and the wind speed is 0.36-0.54m/s (guide value). There should be data to prove the status of one-way flow and verify it.

If it is a non sterile preparation, the level of the weighing cover can be defined as consistent with the level required by the weighed material. However, while maintaining negative pressure and preventing cross contamination of materials, the weighing cover should also ensure that the airflow of the weighing cover will not affect the weighed materials. Therefore, the weighing cover should also test the wind speed on the premise of ensuring that the smoke is acceptable (see the schematic diagram of airflow). The wind speed of weighing hood in non-A environment can be measured according to the reference value given by the supplier.

Suzhou Pharma Machinery Co., Ltd. specializes in the production of purification equipment such as air shower, transfer window, negative pressure weighing cover and dust-free workshop purification engineering. It has been focusing on purification equipment and purification engineering for many years, with rich experience and high reputation. Welcome friends in need to consult and communicate

                 

                 

Suzhou Pharma Machinery Co.,Ltd.

2022/09/04

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