The cleanroom versus barrier isolator debate

This query was submitted by a reader to Doug Theobald, a frequent contributor to CleanRooms magazine, a certified facilities manager, and the Orange County-Los Angeles general manager of Controlled Contamination Services LLC (Anaheim, Calif.).


I have read two of your very well written articles about the new 797 rules from USP.

We at this time do not have the space to put in a full-blown cleanroom. We are told by the barrier isolator salesman that an isolator is all you need.

It seems strange that the USP goes through all these requirements and suggestions and so on, and then an isolator in the corner of the pharmacy department meets all the 797 guidelines?

What is your take on being able to use a barrier isolator in a hospital environment versus [using] a cleanroom? Do you have the isolator in a separate room with an ante area, to reduce traffic, particles, etc.?

Tom Silver
Staff Pharmacist
Howard Community Hospital

Theobald's response

Your question is very valid and not unexpected. First of all, the operative word here is "guidelines." If you have read my articles [see "USP 797: Sterile compounding and room design," CleanRooms June 2004, p. 12 and "USP 797: Contamination sources—control and remediation," CleanRooms August 2004, p. 12], then you understand the "why" of USP 797, although you may not have personally experienced any sort of adverse problems in your own sterile compounding. Nevertheless, such events have occurred and the USP 797 guidelines have been drafted as a result.

The guidelines were developed with the intention of giving each state a "template" with which to work to either develop their own response or, as many have done and are doing, simply adopt. The criteria delineated in the USP 797 for all risk levels calls for an ante/gowning "area."

Addressing your question: I do not know the status of the state of Indiana's stand on USP 797. However, I would like to recommend that you take a look at where you think they are going with it. The information that I am providing is designed to simplify the process and assist in the understanding of the (potential) requirements.

There are some basics that I recommend: A) the need to control the environment, B) the control of ingress and egress of personnel and products, and C) prevention and remediation of contamination. A barrier isolator is one component in achieving these basics. Obviously, each existing environment has its unique challenges. It is my hope that through this series of articles and subsequent communications I can aid in the cost-effective transition. Bottom line: stick to the basics and have a plan.

Douglas K. Theobald
Controlled Contamination Services LLC