Restricted Access Barrier Systems Explained

June 05, 2023

Pharmaceutical laboratories and manufacturing facilities have the ensure the cleanest, safest possible conditions to protect the public and their reputations. One of the most important elements found in these areas is a restricted access barrier system (RABS), also known as a pharmaceutical isolator, which serves to provide additional levels of control in aseptic environments.

What Constitutes a Restricted Access Barrier System?

As defined by the International Society for Pharmaceutical Engineering, RABS are used inside ISO 5 to8 cleanrooms. There are two main types: open and closed. An open RABS allows for human interventions inside the enclosure through specialized openings in the barrier, while closed RABS incorporate high integrity transfer ports that continually feed product into the RABS with automated systems to fill, stopper, and cap to limit human interaction even further. Closed system RABS also utilize integral decontamination processes which again reduce the possibility of contamination by human introduction. Both use ISO 5 unidirectional airflow to prevent contamination within the critical area. Workers use glove ports to handle materials or correct issues during a process from outside the enclosure while still being physically separated from the surrounding area, and all parts that come into contact with the product are sterilized prior to entry.

Another variation of RABS would be Compounding Aseptic Isolators (CAI) and Compounding Aseptic Containment Isolators (CACI) intended for use in sterile compounding. These compounding RABS are considered open RABS and have the same means of limiting human interaction with product but are not completely equivalent to a pharmaceutical RABS and are outside the purview of this article. One common misnomer for RABS would be the term “glovebox”. While these systems do resemble each other at a glance, pharmaceutical RABS utilize positive pressure to prioritize product protection whereas a glovebox or class 3 BSC are run under negative pressure with more stringent requirements on the exhaust system to prioritize personnel and environmental protection, often with no product protection at all.

How Do RABS Work?

RABS can be either passive or active. In a passive system, its air supply to the internal HEPA filters is drawn from the surrounding cleanroom where it is located. An active system uses an attached air-handling unit that may draw from outside air and or return air from the facility that is temperature, humidity, and preliminary particulate control prior to introduction to the RABS internal HEPA filters.

Why are RABS Necessary?

Without these systems in place, there is a much higher risk of pharmaceutical products being exposed to particulates in the air that may contaminate them. In addition, they also serve to protect workers from dangerous chemicals that may be used during testing or manufacturing.

Trust Technical Safety Services

As the leaders in cleanroom certification services, Technical Safety Services is your complete resource when it comes to ensuring you have everything necessary for a safe facility. We’re proud to serve the pharmaceutical industry with a wide array of capabilities to support its mission and provide the most effective products possible. To learn more about everything we can do for you, reach out and speak with one of our representatives today.

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