Closed design RABs have a dedicated air handling system that provides down-flow air that circulates inside physical barriers, together with the provision of fresh air make up and ducted exhaust systems. Materials transfer devices are either a fully closed system, (e.g. alpha-beta rapid transfer ports, and/or devices that connect or interface) are under aerodynamic barrier protection and remain closed to the surrounding environment during transfer procedures. Closed-design RABs may also include a gaseous decontamination system.
An open operation RABS, by definition, provides recognition that the barrier doors can be opened for operator intervention(s), at defined risk assessed stages during aseptic production operations, after the last bio-decontamination step.
Open RABS have an air handling system that is shared with the cleanroom’s ceiling downflow with an air overspill to the surrounding environment. This overspill is directed to a low level under the physical glove-barrier screens and below the points of critical operation; typically 300 mm below and away from the point of fill.
