Volume 9 #2

“Current Comments On Healthcare IAQ Issuesä”

April 13, 2009 Volume 9 No. 2

Newly Published USP <797> Answers to Key CAI/CACI Questions

A pharmacy compounding sterile preparation (CSP) area’s primary function is to provide a safe and clean environment for the workstation in which compounds are prepared by the pharmacy’s professional staff. Workstations, such as a glove box, hood, biological safety cabinet (BSC) or any other device which is used for the preparation of high risk compounds or radioisotope materials, must exhaust all of its air to a dedicated outside vent. It can not be recirculated or exhausted back into the room or to the house air return system.

Just because the pharmacy uses a negative pressure glove box, sometimes referred to as a compounding aseptic isolator (CAI) or compounding aseptic containment isolator (CACI), it does not mean it can be operated in an open, non-ISO rated, environment. Negative pressure glove boxes must be enclosed in an ISO-7 cleanroom environment and their exhaust air must be vented to the outside via a dedicated duct.

Below are direct Questions and Answers from the FAQ page found on the USP website. There are also related engineering questions and answers on the Medical Air Solutions’ website at www.medicalairsolutions.com. Below are two questions relating to the BSC/CAI/CACI clarification:

“Q:114. Are BSCs and CACIs that re-circulate air within a room after filtering through HEPA filters (versus venting to the outside) completely prohibited in the revised USP 797 standard?”

“A:114 When preparing hazardous drugs, the answer is yes. All BSC's CACI's must be vented to the outside. Utilization of re-circulating BSC's or CACI's for non-hazardous CSI preparation is acceptable.”

“Q:70. Can CACI that meets the negative pressure requirement be used if it is placed in a regular room or does the negative pressure CACI need to be placed in a separate negative pressure room?”

“A:70 The CACI shall be placed in a separate negative pressure room. The ISO Class 5 (see Pharmacists' Pharmacopeia, Table 1, page 797) BSC or CACI shall be placed in an ISO Class 7 (see Table 1 above) area that is physically separated (i.e., a different area from other preparation areas) and optimally has not less than 0.01- inch water column negative pressure to adjacent positive pressure ISO Class 7 (see Table 1 above) or better ante-areas, thus providing inward airflow to contain any airborne drug. However, in facilities that prepare a low volume of hazardous drugs, the use of two tiers of containment (example: closed-system vial-transfer device within a BSC or CACI that is located in a non-negative pressure room) is acceptable."

These quotes, taken directly from USP’s web-site, should authoritatively answer any question about CACI or CAI installations. Some manufacturers are NOT telling the truth about their systems meeting this standard. The “USP Frequently Asked Questions” may be viewed in its entirety on the MAS web site at: http://www.medicalairsolutions.com/USP797/usp797FAQ.htm.