A HEPA filter must be able to capture 99.7% of all particulate matter that is at least __________ microns in size.

Question

Quizplus · Accepted Answer

HEPA filters are designed to capture particles that are 0.3 microns or larger in size, making answer choice C the correct option. This size is considered the most difficult particle size to capture, which is why it's used as the minimum efficiency rating for HEPA filters. Answer choice A is too small, as a filter that captured particles that were 0.1 microns or larger would be classified as an ULPA filter. Answer choices B and D are too large, as filters designed to capture particles that were 0.2 or 0.4 microns or larger would be less efficient than a HEPA filter.

A HEPA Filter Must Be Able to Capture 99