Flexible containment has evolved into a mainstay for control of the work environment in the pharmaceutical industry. Whether handling dry powdered products, processing rigs, process waste systems, or controlling waste material releases from cleaning of process equipment and rigid isolators, flexible containment has proven to be an economical and readily disposable technical advance.
The early adoption was a painful decision for management, but with a solid basis of data from test trials using a wide configuration of glovebag and other flexible isolator designs, their reluctance rapidly evolved into a grudging acceptance. The appearance was always a stumbling block because it did not meet the expected industry image of grit finished stainless steel equipment. However, parallel testing of rigid isolators and flexible isolators showed the flexible versions to be equal in emission control capability. The difference was in the cleanability aspect. Flexible isolators merely require wetting of the inside before removal and disposal. Validation of cleaning becomes a non-issue. Not so simple for rigid isolators.
Rigid isolators require a time consuming validated cleaning regimen which is tied in to rigid piping, storage installations, and process automation. Early results using Riboflavin as the test agent usually gave adequate cleaning performance when viewed under Ultra-Violet (UV) light. More recent tests using milled Acid Yellow as the contaminant highlighted the poor performance of rigid containment cleaning practices.
This finding is a common factor. The issue is one of method sensitivity. Whenever a test procedure is improved we discover new challenges. In cleaning tests, Riboflavin is observable at low percentile concentrations under UV light. Acid Yellow is observable to concentration below 50 ppb under the same test conditions. The difference is orders of magnitude in observed sensitivity. Surface cleanability remains a highly subjective area.
The same issue has arisen with emission testing of flexible isolators and other forms of barrier isolation. When testing first started in 1993, the analytical test limit was 0.2μg/cu.m for a water insoluble test agent having a dustiness index of 11%. In 1997, milled water soluble lactose (<3 micron diameter) was adopted as the test agent with an improved detection limit of 2ng/cu.m, although the dustiness index was only 3%. Recent advances have lowered this detection limit to 0.2ng/cu.m. Clients have documented statistically valid performance for our flexible isolators at <0.04ng/cu.m when used for handling a dried Active Pharmaceutical Ingredient. This reflects a cumulative improvement in measurement of 5,000 since inception.
Throughout this evolution, our products have always performed to below the current detection limit as long as they were installed and used properly. Even with orders of magnitude improvement in test methodology, our original flexible isolator designs perform to below the latest method limits. We feel confident that we have consistently achieved our goal of providing our clients with a highly cost effective technology that both protects the worker and meets the more stringent quality requirement of controlling materials migration.
The added values of flexibility in installation, no-risk low cost disposal, and lack of need for an infra-structure system further recommends widespread use of flexible barrier technology in many applications throughout the industry.
Our first major client was a partner in developing new applications. With increasing comfort in the acceptance of flexible containment by their operators, it became the ready solution for many of their ongoing challenges in product contact with potent compounds and sensitizers. Within 2 years, this client had generated flexible containment solutions for many of their global manufacturing plants. By 1995, FabOhio Inc. had developed over 140 discrete designs and shipped multiple fabricated products globally for this client alone. We are proud to have been their partner in proving acceptable use of flexible barriers throughout Pharmaceutical Research and Development, Quality Laboratories, and a wide diversity of manufacturing operations, and more recently in Environmental Control and Biotechnology applications.