I thought a thread with airlines and aircraft that have HEPA filters may be useful, in light of COVID-19.

AA says that "All American Airlines mainline aircraft and most of our regional aircraft are equipped with High-Efficiency Particulate Air (HEPA) filters."

Does anybody know if regional flights with regional jets have them? Specifically, Sky West operating AA (American Eagle) flights with a CRJ 700, and Envoy Air and Republic Airways with the ERJ-175?

BA also states that "All our aircraft are fitted with HEPA filters which remove particulate and bacterial contamination and provide passengers with clean air. They provide the same level of air filtration as hospital operating theatres."