Requirements Needed for Compounding Pharmacies Using USP 797

Requirements Needed for Compounding Pharmacies Using USP 797

Requirements Needed for Compounding Pharmacies Using USP 797

Sterile compounding has its origins in the hospitals of the late 60s and early 70s. Today, pharmaceutical compounding allows millions of patients to get medication that’s tailored to suit their unique needs. Where the drug is injectable, sterility must be maintained through the compounding process to mitigate the risk of infection.

That’s why compounding environments must remain aseptic. The United States Pharmacopeia (USP) developed standards to ensure the sterility of such environments. Smoke testing for air pattern analysis is among the USP’s least observed regulations. Below are guidelines for conducting to USP 797 smoke studies:

  • ISO Class 5 Environment
  • Frequency of Testing
  • Strategies for Best Results

ISO Class 5 Environment

ISO class 5 environment is the technical term for a critical airflow area. The sterility of CSPs (Compounded Sterile Products) is heavily reliant on the efficacy of HEPA filters and overall airflow. That said, you must monitor and manage airflow in the compounding environment.

Smoke studies help you to ensure that the compounding area is both turbulent-free and obstruction-free. USP guidelines require that the critical airflow area be serviced by unidirectional HEPA filtered air. The air should be supplied at a velocity strong enough to blow particles away without any consequence to the direction of flow.

Obstruction-free environments ensure that air flows uninterrupted from the HEPA filters to the critical compounding sites.

Frequency Of Testing

USP 797 smoke test regulations require that air pattern testing be carried out at least twice a year. Results from every test should be stored in an easy-to-retrieve format to ensure they are easily availed to certified testing authorities if the need should arise.

Specialists aside, the results will prove useful if you are ever required to prove compliance with federal airflow testing regulations.

Strategies For Best Results

Airflow visualization not only complies with USP regulation, but it also provides a unique opportunity for training personnel. Ensure that you use every testing opportunity to educate and sharpen compounding personnel.

The more compounders analyze the results, the better they get at determining the most aseptic compounding techniques. The ability to visualize airflow, for example, allows compounders to identify regions with abundant air. That will consequently enable them to determine optimum areas for compounding.

The next strategy to ensure you always have the best compounding results has to do with how you time your airflow tests. Two scenarios justify doing more tests than is required by the USP:

  • Renovations
  • Movement of Objects


Renovations have a significant influence on airflow. Since compounding results are affected by the least changes in airflow, make a point of carrying out smoke tests every time you undertake substantial renovations.

Movement of Objects

The relocation of big objects in critical areas, like entrances, may also affect air velocity and flow. That’s why it’s crucial to conduct a smoke test following such relocation.

That said, it would be impractical to call in a specialist every time objects are relocated. That’s why you need to train an employee to conduct the tests. They, however, can’t perform the two annual tests required by the USP, only USP approved specialists are allowed to do compliance tests.

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