Maintaining the sterility of an environment where pharmaceuticals are prepared protects both patients and pharmacy staff. That is why the Food and Drug Administration (FDA), state boards of pharmacy and accrediting agencies such as the Joint Commission and the Pharmacy Compounding Accreditation Board enforce the standards of the United States Pharmacopeia's (USP's) General Chapter 797 Pharmaceutical Compounding—Sterile Preparations, which is commonly known as "USP 797."

First issued in 2004 and revised in 2008, USP 797 established the first comprehensive quality standards surrounding the design of and procedures used in sterile compounding areas. As the standards state, they apply to all persons who prepare compounding sterile preparations (CSPs) and all places where CSPs are prepared, stored and transported.

To comply with USP 797, health facilities professionals must determine the risk level of the compounding done in their facilities, perform a practice gap analysis of the compounding activities and develop an action plan for compliance.

Maintaining cleanliness

A compliance action plan should include written procedures to standardize such tasks as gowning, gloving and hand washing. Other procedures might cover quality assurance, sampling protocols, spill cleanup, personnel training requirements and the regular maintenance of cleaning logs.

Also, compliance action plans should include a formalized cleaning plan. The main goal of the cleaning plan is to minimize air particulate contaminations introduced into the clean room environment by pharmacy staff and the products staff use. The plan should include scheduled cleanings of the anteroom and compounding area based on the classification of the room and surface area, as designated by the USP 797 guidelines.

Additional tips include the following:

Personnel. Allow only staff specially trained in high-level disinfection, similar to operating room housekeeping staff, to clean the clean room. These employees must be trained in using 70 percent isopropyl alcohol for cleaning sterile compounding areas. Housekeeping staff must comply with written procedures, donning appropriate personal protective equipment before entering a clean room and never entering outside of established cleaning times. Make sure pharmacy staff remove any open products from the clean room before housekeeping staff enter.

Scheduling. Staff must clean countertops, shelving, vents, anteroom sinks and storage bin surfaces daily at the beginning of the work shift prior to compounding. Pharmacy staff must clean every 30 minutes during continuous compounding. This means pharmacy staff should work closely with housekeeping to ensure enough cleaning supplies (e.g., microfiber cleaning cloths and wipers) are on hand. Housekeeping staff should clean the floors each evening. They should clean walls, ceilings and storage shelving at least monthly. Also monthly, staff must "terminally" clean the room, similar to surgical suites. Before terminal cleanings, pharmacy personnel must guarantee that compounding has been completed for the day.

It can take about two hours to clean a clean room, and one to two hours to clean the anteroom in two separate sessions. The use of separate sessions can minimize workflow disruption. To minimize cleaning time, some hospitals use wire shelves and minimize anteroom inventory, limiting them to a four-day supply. The hazardous drug room has minimal inventory and takes about one to two hours to clean.

Supplies. In a hospital environment, the infection control department usually approves clean room cleansers. High-level disinfectants destroy microorganisms with the exception of highly concentrated bacterial spores. Personnel should wear gloves to protect themselves from exposure to these cleaning agents. Material safety data sheets must be available for all cleaning agents and be part of a hospital hazard communication program. Supplies must be non-shedding and dedicated to the clean area to prevent contamination from other areas of the facility. Staff also must clean tools prior to taking them into the sterile compounding area.

Methods. Staff should work from far to near, starting at the farthest corner of the room and proceeding to the door. During the cleaning process, check for expired medications and products. Staff must clean countertops, shelving and storage bin surfaces with germicidal disposable wipes and use a high-level disinfectant on carts used to transfer products and on the outer surface areas of the laminar flow hoods. Vents should be wiped with a clean cloth before the floor is cleaned. While anti-fatigue mats can be used, they must be cleaned daily as well. After cleaning the room, have housekeeping staff document their activity on a log sheet co-signed by the pharmacist.

Waste disposal. Pharmacy staff should move trash from the clean room to the anteroom twice daily. Staff should dispose of sharps in red biohazard sharps containers and dispose of hazardous waste in colored containers, based upon regulated waste streams and hospital policy. Pharmacy personnel should fill and seal these containers before the housekeeping or environmental health and safety departments assume responsibility for disposal.

Monitoring sterility

USP 797 points out that airborne contaminants are more likely to infiltrate critical sites than contaminants found on the floor or surfaces. The action plan should include environmental sampling to monitor air quality regularly for viable and nonviable particulates. Table 1 of USP 797 provides particulate matter limits.

In Class 100 or International Organization for Standardization (ISO) 5 air environments, the particle per cubic meter must be no more than 3,520 particles per cubic meter in a size of 0.5 micrometer (um) or larger when counted at representative locations. Take the measurement no more than 1 foot away from the work site, within the airflow, and during filling and closing operations.

Supporting areas where less significant activities occur, or clean room areas where the laminar flow stations are located, must meet at least Class 100,000 (ISO 8) air quality. The activities conducted in supporting clean room areas determines their classifications. The FDA recommends that these areas immediately adjacent to the aseptic processing line meet, at a minimum, Class 10,000 (ISO 7) standards under dynamic conditions.

Both air and surface samples may be taken. Staff should remember to document their sample procedures and include the time of day. The current guidelines recommend impaction on a media plate for culturable air sampling. Settling plates, which were referenced in earlier editions of USP 797, are now specifically discouraged.

Contact plates or swabs should be used to sample the surfaces of all ISO-classified areas periodically. Regularly sample clothing, gloves and other gear of operating personnel. Media-fill tests should be conducted annually to verify that each person authorized to make sterile compounds can do so aseptically.

Conduct a formal risk assessment to determine where staff should sample for viable particles. Chosen sites must feature multiple locations within each ISO Class 5, 7 and 8 environment and in the segregated compounding areas at greatest risk of contamination, such as work areas near the ISO Class 5 environment. Sample locations prone to contamination during compounding activities and during other activities such as staging, labeling, gowning and cleaning.

Sampling must include zones of air backwash turbulence within laminar airflow workbenches and other areas where air backwash turbulence may enter the compounding area. Consider how the sampling method may affect the unidirectional airflow within a compounding environment.

For low-risk-level CSPs with a 12-hour or less beyond-use date that are prepared in an ISO Class 5 environment, sample inside the ISO Class 5 environment and surrounding areas.

Commercial environmental laboratories can help staff acquire the correct media and establish sampling protocols. In general, use a microbiological medium for bacteria or a medium that supports fungal growth for fungi. Media used for surface sampling must be supplemented with additives to neutralize the effects of disinfecting agents.

Some more specific advice includes the following:

Air. Use an impaction sampler to collect as much air as possible without drying the media. The 2008 revision bulletin suggests a sampling volume of 400 to 1,000 liters of air, but manufacturer recommendations should be followed.

Surface. Use contact plates or swabs. When swabbing, cover at least 24 square centimeters (cm2) but no more than 30 cm2.

Gloved finger. Use contact agar plates to sample gloved fingertips after compounding CSPs. This sampling must occur outside of the ISO Class 5 environment. Gloves should not be disinfected with isopropyl alcohol immediately before sampling. Touch the agar with the fingertips of both hands to create small impressions.

Determine elevated levels of viable colony counts by consulting USP 797 or chapter 1116 of the USP Microbiological Evaluation of Clean Rooms and Other Controlled Environments. Regardless of colony forming unit (cfu) counts, corrective actions will depend on the type of microorganisms identified. If highly pathogenic microorganisms are found, staff must take immediate action. Assistance from a microbiologist, infection control professional or industrial hygienist may be required.

When a cfu count exceeds its action level according to Table 4 of USP 797, eliminate the problem, clean the affected area using written procedures as guides and resample. Watch for data trends to evaluate the overall control of the environment. If necessary, re-evaluate personnel, operations and facilities to identify opportunities for improvement.

Go to the source

Pharmacy regulations vary by state and organization. Even the seemingly universal USP 797 is open to interpretation. To ensure compliance, health facilities professionals should read and interpret the USP 797 standards for themselves.

Linda D. Lee, Dr.P.H., is director of operations for Waste Management Healthcare Solutions, Houston. She can be reached at

About this Series

This bimonthly self-study series is a joint project of the American Society for Healthcare Environmental Services and Health Facilities Management. Click here  for information on obtaining continuing professional education credit.