USP 797

Pharmaceutical Compounding - Sterile Preparations

What is required for your Buffer zone?

USP Chapter 797 was released to the public in 2004 and has classified Sterile Compounding into 3 risk groups: Low, Medium and High Risk. For each risk level, the Chapter establishes staff responsibilities and training, quality control processes, competence assessment, environmental quality and control, and quality assurance program requirements.

USP 797 has been adopted by several states and is currently under review by many others (check with your state Board of Pharmacy). States have the option to adopt 797 verbatim or to edit the standards into pharmacy regulations (Missouri and Texas have sterile compounding regulations, New Jersey’s requires that the buffer zone be ISO 6 / Class 1,000). Additionally, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) is enforcing USP Chapter 797 within their standards. The JCAHO may require stricter compliance to 797 than the state Board of Pharmacy.

USP Chapter 797, as it applies to cleanrooms (Buffer Zones), is general in nature but refers to the International Standards Organization, ISO-14644 standard for cleanrooms. All Sterile compounding is to be performed in an ISO 5 (class 100) environment that is surrounded by an ISO 8 (Class 100,000) Buffer Zone (cleanroom), ISO 7 (Class 10,000) in 2006. A barrier isolator does not have to be contained in an ISO-rated space unless recommended by the manufacturer.

A “Buffer Zone” in the simplest form, is an environment that separates the compounding room from the surrounding ambient (unrated) area and is to be constructed from low-particle-generating materials that can withstand continuous cleaning. ISO standards require that the buffer zone be maintained under positive pressure and that airborne particles be limited in compliance with ISO 8 requirements. ISO 7 (Class 10,000) will be required in 2006.

You may be able to meet the specified standards with as little as a fresh coat of paint (water-based epoxy), the addition of 1, 2 or 3 new walls (fixed or modular), a new cleanroom ceiling, HEPA-filtered air, and a coved vinyl floor.

There are many ways to meet USP Chapter 797’s requirements for sterile compounding areas. Cleanrooms can be economical, installed in as little as 1-3 days (over a weekend), and designed to use your existing laminar flow hoods in a USP Chapter 797 compliant environment while conserving space. Evaluate all your options first. Modular Cleanrooms can provide preliminary cost estimates for a cleanroom within 1-3 days.


Class Limits




Annual Maintenance Contract.

1) AHUs, Cleanrooms, Laminar Flow work stations.
2) Largest inventory of air filters [20, 10, 5, 3 micron] pre filters and hepa filters.
3) Room differential pressure management.
4) Periodical testing & Validation of cleanrooms.