Commercial airlines love to boast about how safe cabin air is, and how powerful HEPA filters scrub out bacteria and viruses. What they prefer you don’t know: HEPA filters don’t stop engine fumes or chemical vapors—and those toxic substances seep into cabin air far more often than the public realizes.
How common are these so-called “fume events”? No one knows. The FAA reportedly blew off a Congressional mandate to track them.
