Home  > INFO CENTER  > BLOG  > 

What is a Clean Room in USP 797?

What is a Clean Room in USP 797?


If you are involved in compounding sterile preparations (CSPs), such as injections, eye drops, or inhalations, you may have heard of USP 797. This is a chapter of the United States Pharmacopeia (USP) that sets the standards and guidelines for ensuring the quality and safety of CSPs. USP 797 covers various aspects of CSPs, such as personnel training, environmental monitoring, storage, and labeling. One of the most important sections of USP 797 is the one that deals with the facilities and engineering controls for CSPs, especially the clean room.

A clean room, also known as a buffer area or an iso 7 cleanroom, is a designated space where CSPs are prepared in a controlled environment to minimize the risk of microbial and particulate contamination. A clean room must meet certain requirements for air quality, temperature, humidity, ventilation, and cleanliness. According to USP 797, a clean room must have the following characteristics:

- It must have a positive pressure relative to the adjacent areas to prevent the ingress of contaminants.

- It must have a high-efficiency particulate air (HEPA) filter that removes at least 99.97% of particles 0.3 microns or larger from the air.

- It must have at least 30 air changes per hour (ACPH) to dilute and remove airborne contaminants.

- It must have a temperature between 20°C and 25°C and a relative humidity between 30% and 60% to prevent microbial growth and preserve the stability of CSPs.

- It must not contain any sources of water or floor drains that could harbor microorganisms or introduce moisture into the air .

- It must be cleaned and disinfected regularly with appropriate agents and supplies to eliminate any residual microorganisms or particles .

- It must be certified and recertified at least every six months by a qualified professional to verify that it meets the required standards .



A clean room is not enough to ensure the sterility of CSPs. Within the clean room, there must be a primary engineering control (PEC), such as a laminar airflow hood or a biological safety cabinet, that provides an iso 5 cleanroom environment for the actual compounding process. A PEC must have its own HEPA filter and airflow system that creates a unidirectional flow of sterile air over the compounding area. A PEC must be located away from any sources of disruption or contamination, such as doors, windows, sinks, or vents. A PEC must also be cleaned and disinfected before and after each use with sterile 70% isopropyl alcohol (IPA) .

In addition to the physical design of the clean room and the PEC, USP 797 also specifies the behavioral requirements for the personnel who work in them. The personnel must undergo proper training and evaluation to demonstrate their competency in aseptic technique and CSP preparation. The personnel must also follow strict personal hygiene and garbing procedures to prevent themselves from introducing any contaminants into the clean room or the PEC. The personnel must wear shoe covers, face masks, hair covers, gowns, gloves, and eye protection when entering the clean room and performing compounding activities .

The purpose of having a clean room in USP 797 is to protect the patients who receive CSPs from any potential harm caused by contamination or infection. By following the standards and guidelines of USP 797, compounding personnel can ensure that they are providing CSPs that are safe, effective, and consistent.



Suzhou Pharma Machinery Co.,Ltd.



Chat Online
Chat Online
Leave Your Message inputting...
Sign in with: