RABS – a flexible containment solution
?Luca Arrighi and Germana Molinari, of Foster Wheeler Italiana, argue the use of restricted access barrier systems can be applied to containment of blister packing lines, removing the need for multiple suites
?Dust containment, and therefore mitigation of the risk of cross-contamination, is the great challenge in designing an oral solid dosage (OSD) multi-product facility.
A common approach to this kind of operation has been to segregate process equipment, with a dedicated production room for each unit. Although this solution reduces the risk of cross-contamination, it is very expensive and can mean a delay of several months during the revamp of an existing production suite. Any alternative solution must protect both the operator and the product and avoid, or limit to an acceptable level, any risk of cross-contamination.
With this in mind, Foster Wheeler investigated the possibility of applying the restricted access barrier system (RABS) concept, developed for aseptic production, to segregate the OSD production equipment. We determined that with proper modification, RABS could be used successfully, limiting investment cost, reducing facility downtime, and satisfying the regulatory and safety requirements.
Specific application
A multinational pharmaceutical company sought to revamp the primary packaging area of an OSD facility where several blisterpacking lines were installed in a common room, but each dedicated to different products giving rise to cross-contamination issues.
The project challenge was to reduce the revamping intervention time as well as the plant modification, solving the containment issue at blister machine level. The project solution was reached following thorough analysis of the product and operational key features, using a decision tree as illustrated below (figure 1).
As the product was a low potent solid, handled with little spreading activity in an open environment, the decision tree process concluded that a closed restricted access barrier system (C-RABS) would offer the correct containment level by circulating the air in the RABS working area and exhausting it outside rather than within the production room.
The C-RABS (see figure 2) has been designed as a tool to be integrated into the process and is capable of providing a flexible containment solution when combined with adequate procedures and product, material and personnel demands:
- personnel with standard gowning; without personal protective equipment
- personnel intervention in working area with gloves;
- personnel access to working area after internal wetting phase followed by enforced air extraction before opening doors (interlocked during operation)
- batch material transfer through tight connections, and
- continuous material transfer through ‘mouse holes’ provided with local extraction.
The timescale for the project was challenging, with production downtime limited to two months:
- design and construction: months 1 & 2;
- installation, start-up: month 3, and
- validation: month 4.
Foster Wheeler’s project team achieved this schedule and the blisterpacking machines, complete with modified C-RABS, are operating successfully, meeting key regulatory and safety criteria.
