USP 797 clean room requirements for sterile compounding
The United States Pharmacopeia (USP) is an official public standards–setting authority for all prescription and over–the–counter medicines and other health care products manufactured or sold in the United States.
USP chapter 797 is specific to pharmaceutical compounding - sterile preparations, which became official in June 1, 2008.
I have gone to several seminars regarding USP797 requirements. This chapter is written because there are a few deaths regarding "sloppy" compounding by pharmacists.
The main point of USP797 relating to my pharmacy practice is that I must be working in an ISO 5 laminar flow hood located in an ISO 8 room.
I have an ISO 5 vertical laminar flow hood. What I need to achieve is an ISO 8 clean room:
My compounding room is 10x13x10 feet (vol =1300 cf). There is a HVAC supply vent in the ceiling. In one of the seminars, Air-in-space, a french company introduced a unit called Plasmair to achieve ISO 7 in an ideal room that was around the size of my compounding room. The Plasmair's output is 300 CFM on low, 600 med, and 1180 on high. In a demo, Dr Vance Bergron was able to achieve ISO 8 within 2 minutes on high (1180 CFM), about 2 air changes for this room. Of course, ideally, the HVAC was off. They claimed that since the Plamair cleans the air so fast, it requires very little HVAC intervention. So far, the Plasmair is currently in use in hospitals around the world. They are trying to market this for pharmacies like mine.
Pros - 45 degree air output unidirectionally so I can place it in a corner of my compounding room; the speed to achieve ISO 8.
Con - Too big for my compounding room; expensive (>$10k)
I have 3 dilemmas:
1. My compounding room has an opening due to a lowered wall. From wall to ceiling of 2 sides is around 2 feet. I need to enclose this space with non shedding material. The 2 sides of the walls is constructed with Fabtak, which I believe is coated with non-shedding vinyl. The other 2 sides are gypsum based drywall with several coats of paint, which may emit VOC's. However, USP797 says nothing about VOC's, just ISO 8 particle count control. I guess VOC's stay in the air (at least at room temperature), so they cannot contaminate compounding surfaces. On the other hand, particulates and microorganisms like mold spores (fungi), viruses, and bacteria can.
2. I've been looking for a smaller unit like the Plasmair, but can't find one. So far, I found the IQAir Cleanroom H13, but its output is not unidirectional and creates turbulence. Anyhow, the H13's max output is 280CFM. That means I need a minimum of 5 min for a single pass for my 1300 cubic foot room (correct me if I'm wrong with my math). To be sure I can achieve ISO 8 with HVAC off, I'll need at least 5 passes, which will be equivalent to around 25 minutes. Does this sound reasonable to you? I can perhaps leave the unit on 24/7, but we're only open for 12hrs/day M-F. I ordered a Dylos DC1100 with PC interface to monitor. Realistically though, to create a comfortable working environment, the HVAC would be cycling on and off. This is the reason why I'd like the HVAC fan "on" at all times to create a positive pressure in the compounding room or I can purchase the ducts that can adapt to the H13 to create the same effect. Any suggestions?
3. The HVAC - I plan to put a MERV 11 filter in the return duct, to help reduce the particles exiting the supply duct in the compounding room. Since I only need this compound room to be ISO8, are there filters (HEPA or close to HEPA) that I can place in this particular supply duct without having too much of a pressure drop in addition to the MERV 11 return duct filter? Suggestions?
We have had good results working with Aeromed on these types of applications.