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7 USP 797 Standards that are Important to Ensure Sterile Compounding

Improved safety outcomes for patients who receive compounded sterile preparations (CSPs) can be traced to the issuance of U.S. Pharmacopeia Chapter <797>: Pharmaceutical Compounding – Sterile Preparations. The intent of USP 797 is to prevent patient harm through minimum practice and quality standards expected from any entity or individual involved in CSP storage, handling, preparation and transportation. By carefully adhering to USP 797 standards, the compounding pharmacy consistently executes critical procedures and processes, and therefore reduces the risk of causing patient harm.

USP 797 standards cover three key areas – personnel, engineering/facility design and environmental controls. The chapter provides requirements for each area designed to ensure safe, sterile compounding.


One of the most important USP 797 standards requires well-trained and routinely-monitored personnel. Repeated studies conclude that personnel represent the number one source of microbial contamination in a cleanroom.1 Given this fact, attention must be given to personnel techniques and training to achieve and maintain USP 797 compliance.

Wear sterile gloves

Studies have shown significantly higher rates of positive media fills among operators who begin with non-sterile gloves, compared to those who utilize sterile gloves. To avoid this potential contamination source, use only sterile gloves. Even nonsterile gloves disinfected with 79 percent isopropyl alcohol have been shown to introduce contaminants.2

Properly garb – regardless of compounding risk level

Even if your compounding facility is low-risk, proper garbing is essential. Personnel should always wear shoe covers, face masks, hair covers and gowns, regardless of whether they work in a low, medium or high-risk compounding environment.

Train, monitor, and test

Compounding personnel can be the pharmacy’s best asset. Ongoing training and evaluations are key for evaluating the competency and skill of personnel, and avoiding negative patient outcomes.

Engineering/facility design

The second key area of USP 797 compliance involves a properly designed facility. Some important requirements include:

Air quality

Air quality and cleanliness can significantly impact microbial contamination, making this a high priority for facility design. A high-quality air ventilation design is critical, as well as installation and regular maintenance of high-efficiency particulate air (HEPA) filters.

Line of demarcation (LOD)

The facility should be designed so that there is a clear line of demarcation in the ante-area or segregated compounding area that separates the dirty area from the clean area. This continues to be an area of low compliance; in the 2014 USP Chapter <797> Compliance Survey, only 57.5% of respondents reported LOD compliance.3

Environmental controls

A robust environmental compliance management program provides data to track facility integrity, air quality, and microbial levels; it enables the pharmacy to make adjustments if deteriorating results are observed. Important environmental USP 797 standards include:

Microbial and particulate monitoring

The compounding pharmacy must perform semi-annual monitoring for viable microbial (bacterial, mold, fungus) contamination in the air, gloved fingertips, surface contact plates, and particulates.

Environmental sampling plan

Only 54 percent of respondents in the 2014 USP Chapter <797> Compliance Survey3 reported having an Environmental Sampling Plan that included the following: sample locations, collection method, sampling frequency, air sample volume (for viable air samples), time of day in relation to compounding and action levels.

What do you feel are the most difficult standards to comply with for USP 797?


1. Galloco J, et al. Aseptic Processing: A Review of Current Industry Practice. Pharmaceutical Technology. 2004; 28(Oct 10): 128.

2. Kastango, Eric S. 33 Tips for USP <797> Success. Pharmacy OneSource, Inc. 2006.

3. Douglass, Kate, Kastango, Eric S, MBA, RPh. The 2014 USP Chapter <797> Compliance Survey. Pharmacy Purchasing & Products. October 2014, Vol. 11 No. 10.

A step by step guide to USP 797 compliant pharmacy. Download now.

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