What is the purpose of the HEPA filter in a biological safety cabinet?

The purpose of the HEPA (High-Efficiency Particulate Air) filter in a biological safety cabinet is to maintain sterile conditions by effectively trapping airborne particles, including microorganisms, allergens, and other contaminants. HEPA filters are designed to capture at least 99.97% of particles that are 0.3 microns in diameter, which includes many harmful pathogens. This filtration is crucial for protecting both the laboratory personnel and the samples being handled from contamination.

By ensuring that a clean, sterile air supply is maintained within the cabinet, the HEPA filter plays a vital role in preventing cross-contamination and ensuring that biological experiments can be conducted safely and effectively. The sterile airflow created by the HEPA filter also helps to create a clean working environment where aseptic techniques can be employed without introducing outside contaminants.