HEPA cartridges are effective in filtering out particles of which size or larger?

HEPA (High-Efficiency Particulate Air) filters are specifically designed to capture airborne particles, including dust, pollen, mold spores, and other contaminants. The effectiveness of HEPA filters is defined by their ability to trap particles of a certain size.

The standard for HEPA filters typically states that they can capture at least 99.97% of particles that are 0.3 microns in diameter or larger. This size is crucial because it represents the most penetrating particle size (MPPS), meaning that particles of this size are the most difficult for the filter to capture.

Particles that are smaller than 0.3 microns may be captured as well, but 0.3 microns is the benchmark used for the efficacy of the filter. Therefore, selecting this size indicates an understanding of HEPA filter performance in effectively removing hazardous particles from the air, relevant for scenarios involving microbial remediation, where air quality is a significant concern.

In summary, HEPA cartridges are recognized for their effectiveness in filtering out particles 0.3 microns and larger, making this the correct answer.