Airflow visualisation in an aseptic facility

Design and Build |

Abstract

A large amount of filtered air is required to remove or dilute contaminants for satisfactory operations in a critical cleanroom environment. Airflow visualisation studies can assist in knowing how air moves in a cleanroom and affects any contamination that might be present. Should problematic airflow patterns occur, the manager of the cleanroom should either attempt to engineer these out, undertake a suitable risk assessment or target environmental monitoring samples towards the areas of concern.

Figure 1: Diagram of filtration transfer in the filtration room
The stronger airflows are represented by the thicker arrows. As illustrated in the diagram, there is a strong airflow away from transfer ports and no dead spots, airflow is constant. The airflow over the transfer port was generally in a horizontal unidirectional pattern

Airflow visualisation is a useful method for risk assessment of pharmaceutical processing. Dr Tim Sandle, from the Pharmaceutical Microbiology Interest Group (Pharmig), demonstrates how, using an airflow study at a filtration transfer activity in an aseptic filling facility.

Because a cleanroom is designed to control the concentration of airborne particles, a large amount of clean (filtered) air is required to remove or dilute contaminants for satisfactory operations in a critical cleanroom environment. Although this is controlled through Heating, Ventilation and Air Conditioning (HVAC) systems and assessed through the measurement of physical parameters, e.g. airflow rates, for critical operations such as aseptic filling, a visualisation of the air movement is required.¹

Knowing how air moves in a cleanroom or clean air device is important to help understand how the air affects any contamination that might be present. This can be achieved through airflow visualisation studies.

• Bio Products Laboratory
• Pharmig