Which ISO class air quality must a C-PEC provide or better for sterile HD compounding?

• A. ISO class 5
• B. ISO class 4
• C. ISO class 3
• D. ISO class 7

Answer: (A)

The key idea is that the area where sterile hazardous drugs are actually mixed must be extremely clean to protect both the product and the person handling it. The C-PEC (compounding aseptic containment primary engineering control) is the device that creates that immediate environment, so it must deliver ISO Class 5 air in its critical work zone. This level of cleanliness keeps particulates and potential contaminants at very low levels, which is essential for sterility and safety when working with hazardous drugs. Any cleaner class, such as ISO 4 or ISO 3, would also meet the requirement, but ISO 5 is the minimum. ISO 7 is a less-clean environment and is not sufficient for the C-PEC’s interior, though the surrounding space might be managed to that standard.