Q: If a biological safety cabinet (BSC) puts out “clean air”, does the BSC need to be vented to the outside?

A: The NIOSH alert (see web links) requires 100% ventilation to the outside of a BSC or CACI used for volatile hazardous drug compounding. USP <797> recommends 100% ventilation of either unit to outside air. BSCs do not put out clean air because of leakage from the front of the BSC and because volatile (gaseous) exhaust is not trapped by HEPA filters. If a BSC or CACI is vented 100% to the outside, there is no requirement that the buffer room be vented 100% to the outside. Per <797>, the buffer room in which hazardous drugs are compounded must be negative pressure except under certain very low work volume circumstances. A negative pressure buffer room should have HEPA filtration in the exhaust air ducts from the room. You might contact CETA for more precise HVAC engineering specifications e.g. CETA CAG-003-2006 in other web links.

Q: Is it necessary to garb when using a compounding aseptic containment isolator (CACI)?  Chapter <797> suggests gown, masks, hair cover, shoe covers and double gloves are necessary when using a CACI, and compliance with manufacturer's recommendations when using a CACI.

A: USP <797> says that when CAIs and CACIs are the source of the ISO Class 5 environment, the garbing and gloving requirements for compounding personnel should be as described in <797>, unless the isolator manufacturer can provide written documentation based on validated environmental testing that any component(s) of PPE or personnel cleansing are not required. I would be very reluctant to use less garb when handling hazardous drugs because spills, leaks etc. can always happen inside or outside the isolator.  The main thing in handling hazardous drugs is to protect the worker from contact with hazardous drugs.

Q: USP Chapter <797> does not address decontamination of a CACI.  The ASHP Guidelines on Handling Hazardous Drugs suggests to decontaminate isolators.  The product they suggest is SurfaceSafe which is a towelette.  That is not practical for an isolator.  Our isolator company’s guidelines state that cleaning should be followed by rinsing with sterile hot water which is totally impractical.

A: Decontamination of hazardous drug compounding areas both inside and outside of BSCs or CACIs is a contentious issue.  Some believe that sodium hypochlorite, the active ingredient in SurfaceSafe, is the best decontaminating chemical.  But active chlorine compounds are extremely corrosive and sometimes unpleasant for staff members to be near.  Without 100% exhaust to the outside of a CACI (and with any BSC) the smell does get out into the room.  An alternative that I have heard is just to wash the interior of the CACI with a detergent solution and rinse with sterile water (e.g. sterile water for irrigation in a pour bottle).  The main objective with decontamination is mechanical scrubbing to remove the hazardous residue.  You have to be careful to dispose of the wash water and wipers as hazardous waste. Here is what one government guideline (http://www.guideline.gov/summary/summary.aspx?doc_id=4152) says about decontamination:

"Cleaning of the Biologic Safety Cabinet (BSC) should be performed at the end of a session of preparation activities, such as at the end of a shift or day of work, depending on the volume of hazardous drug preparation. Traditionally, a cleansing agent followed by ethanol has been used to clean and disinfect work surfaces of the BSC; however, ethanol does not deactivate hazardous drugs. Many drug manufacturers recommend sodium hypochlorite (bleach solution) to inactivate cytotoxic drugs. Sodium thiosulfate solution inactivates the bleach, thus reducing the potential for corrosion of work surfaces. Oxidation from the bleach followed by nucleophilic substitution from sodium thiosulfate result in the chemical degradation and mutagenic inactivation of many commonly used chemotherapy drugs. A product called SurfaceSafe is the only commercially available product containing these chemicals in the recommended concentrations. It consists of a kit of two packaged pads that are designed to be used on surfaces in and around mixing and administration areas. Decontamination of the BSC should be performed on a regular basis (e.g., weekly, monthly) and whenever there is a spill in the BSC. The operator should wear PPE, including gown, gloves and utility gloves, mask, face shield, and hair covering. The decontamination process involves lifting all removable parts for cleaning and disinfecting. All parts should be decontaminated within the cabinet, not removed for cleaning. Treat all cleaning and rinsing solution as contaminated waste. Discard all PPE in a hazardous waste container."

Q: Our consultant designed our new pharmacy with the sink directly outside of the ante room, because he said that a sink would inevitably grow Pseudomonas which would potentially “splash” all over the room and thus could be easily carried into the buffer area contaminating IVs.  Should our sink be inside our ante/gowning room or should it be outside to avoid contamination?

A: I recommend that the sink be in the anteroom.  The reason has to do with the garbing sequence.  To garb, one covers the dirtiest parts first, shoe covers and hair covers etc. then does the hand-washing at the sink.  The gown comes next before one enters the buffer room where the final hand scrub is done with an alcohol-based solution just before sterile gloves are donned. If the sink weren't in the anteroom, you would have to wear clean garb outside the anteroom to wash hands, then return to the anteroom to put on the gown.  Clean garb should be kept in the anteroom or the buffer room and not worn outside.  Exiting and reentering the anteroom would also be inefficient. Sinks are sources of contamination.  That is why USP <797> requires microbial surface testing.  If pathogens are growing in the buffer room or anteroom, changed procedures for cleaning and disinfecting the environment are in order.  Chapter <797> suggests that a competent microbiologist be contacted about such environmental contamination.

Q: If we use a closed system vial-transfer device (CSTD) in a CACI must we place the CACI in a clean room?

A: The ISO Class 5 CACI must be placed in an ISO Class 7 negative-pressure, buffer room; however, in facilities that prepare a low volume of hazardous drugs (USP <797> does not define low volume), the use of two tiers of containment (i.e. a CSTD within a CACI) that is located in a non-negative pressure room is acceptable.

Except for the final question, ASHP’s FAQs for proposed USP Chapter <797> all still apply to the current USP Chapter <797> and are available at: http://www.ashp.org/s_ashp/docs/files/CRC_FAQ_Proposed_797.pdf