Clean Air and Containment Review
The journal to enhance your knowledge of cleanroom, clean air and containment technology

Issue 19: July 2014

Main Features

Isolators and the User Requirement Specification (URS):
How to avoid making your solicitors rich and your company poor

Tim Coles

This article reviews some of the issues the author has encountered zith URSs (User Requirement Specifications) during a long career in isolator technology. There are two particular areas of concern. The first is the qualification and experience of the URS writer. The second is the logical organisation of the URS. A further point is the design of aseptic isolators produced by companies whose core business is containment. The article goes on to give a suggested flexibility to allow the supplier to use his specialist technology. Finally, there is comment on the need for DQ, the benefit of avoiding repetition and the careful use of must and should to describe the required equipment features. How do you ensure that your clean room or isolator is free from microbial contamination? How do you ensure that your BSL3 laboratory or cabinet is free from dangerous pathogen you are working with? In many instances liquid disinfection cannot be used to reach all parts of the space and is difficult to validate so gaseous decontamination is carried out as an alternative measure.

A history of isolator and containment technology
Part 2: Flexible film isolators

Doug Thorogood

This is the second of five papers that will describe the history and development of isolator and containment technology in the fields of research, medecine and pharmaceutical applications.

The paper commences with the development of flexible film isolators based on designs similar to Trexler's later models and the expansion of the use of such isolator designs by the pharmaceutical industry into sterility testing, aseptic processing and, in containment format, for compounding hazardous products. Hospital pharmacies also picked up the technology for dispensing.

The HEPA filter installation leak test:
Factors influencing the test result and assessing the risk of a pass

Stephen Ryan

The HEPA (High Efficiency Particular Air) filter installation leak tests, checks HEPA and ULPA (Ultra Low Penetration Air) filters for leaks. The test is designed as an on-site test to check HEPA/ULPA filters for integrity after installation. The test is undertaken because HEPA filters are easily damaged if they are not handled correctly during transport and installation. This article is confined to the more widely usded test performed with a photometer.

In the pharmaceutical industry, the result of the test is a well defined pass or fail. However, a number of parameters which influence the result of the test are not routinely accounted for and filters, which have met the acceptance criteria, may in fact fall short of the requirements.

Regulatory Reflections

Non-sterile pharmaceutical manufacturing:
USP Chapter in Development

Tim Sandle

Book Review

Review of 'Pharmaceutical Regulatory Inspections' edited by Madhu Raju Saghee
James H Filer


Nitrex, DOP Solutions, Pharminox, Ecolab, CRC

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