Compounding occurs in which ISO class environment at all times?

Compounding in a sterile environment, particularly for prepared medications in healthcare, is required to take place under specific ISO classifications to minimize the risk of contamination. ISO Class 5 is critical because it defines the environment where the air cleanliness is maintained to ensure that the risk of exposure to viable and non-viable particles is minimized.

This class of environment allows for a maximum allowable particle count of 3,520 particles per cubic meter for particles equal to or greater than 0.5 microns. This is essential in preventing the introduction of microorganisms and other contaminants that could compromise the sterility of compounded sterile preparations.

In practice, ISO Class 5 environments are typically achieved in laminar airflow workbenches or compounding isolators, which provide the necessary protection for sterile compounding activities, aligning with the stringent requirements of USP 797 for aseptic technique. Maintaining this class of environment at all times during the compounding process ensures that the integrity and safety of the medications being prepared are upheld.