Application of negative pressure weighing room in the field of purification equipment
Application of negative pressure weighing room in the field of purification equipmentNegative pressure weighing room, also known as negative pressure weighing hood or weighing hood, weighing room, is an air purification equipment that provides local negative pressure and a local class A environment. It is suitable for special local purification equipment in pharmaceutical, microbiological research, and scientific experiments. The main equipment of the negative pressure weighing room consists of several important parts such as the working area, return air box, fan box, outlet box, and outer box. It is widely used in raw material weighing and metering, antibiotic sampling, hormone drug processing, and some liquid sample processing.Under normal circumstances, the air in the negative pressure weighing room flows from top to bottom through the working area. The flying dust generated during work is pressed to the primary filter and medium efficiency filter at the bottom of the front and then pressed into the static pressure box by the centrifugal fan. After passing through the high-efficiency filter, it is diffused to the air outlet surface and blown out, providing a vertical one-way airflow. Part of the clean air circulates in the working area, and part is discharged to the nearby area so that the working area is in a negative pressure state compared to the external area. The vertical unidirectional airflow in the working area ensures that the dust of the weighing object will go down with the airflow and will not spread to the external area, preventing cross-contamination and protecting the clean environment and the safety of the operators. It is understood that the EU GMP guidelines require that the weighing of starting materials usually be carried out in an isolated weighing room designed according to the purpose. Moreover, according to the Chinese Pharmaceutical GMP Guidelines, it is recommended to operate in an area equipped with a dust removal system to reduce the operator's contact with the product. From the requirements for the weighing of raw and auxiliary materials, it can be seen that the weighing of raw and auxiliary materials requires a dust removal system, a special weighing room, and measures to maintain relative negative pressure or special isolation. In addition, negative pressure weighing rooms are widely used in specific areas of scientific experiments. For example, in chemical experiments, some drugs or chemicals are toxic and may harm experimenters and the environment. The negative pressure weighing room effectively isolates harmful substances and protects the safety of experimenters by providing a local negative pressure environment. Similarly, in some liquid sample processing processes, the negative pressure weighing room can eliminate the interference of splashing liquid on the experimental results. |