Mold Remediation Certification Practice Exam

What is the efficiency rate of a HEPA filter for particles at 0.3 microns?

1. 99.97%

2. 95%

3. 98%

4. 100%

The correct answer is: 99.97%

HEPA filters are designed to capture a significant percentage of particles in the air, and their efficiency is often assessed based on their performance at a specific size of particulate matter, notably 0.3 microns. While HEPA filters can be effective against larger and smaller particles, the 0.3-micron size is particularly critical because it represents a size range that poses respiratory health risks and also corresponds to the most penetrating particle size (MPPS). The rate of 99.97% efficiency means that HEPA filters can trap 99.97% of all particles with a size of 0.3 microns that pass through the filter. This high efficiency is what makes HEPA filters a standard for air quality in environments requiring strict contamination control, such as hospitals, laboratories, and homes dealing with mold and allergens. Other choices do not accurately reflect the well-established performance of HEPA filters at this particle size. While 95% and 98% efficiency figures can apply to certain filtration systems or less stringent filter types, they do not meet the rigorous standards set for true HEPA filters, which must achieve the at least 99.97% capture rate at 0.3 microns. The option of 100% efficiency