VIA Rail

[danbrotherston]

But unless you know all the folks sitting around you, I think there's still reason to wear them on the plane.

Like I said, getting some respiratory infection while travelling is fairly common, COVID is not different in that respect.

No argument there. But using HEPA filters on a modern train (like the new VIA ones) would significantly reduce risk for everyone. Especially since trains usually don't suffer from the same level of congestion as planes and airports.

Oh, I completely agree. I think broadly we should be improving ventilation, although FWIW, I think HEPA is mostly important for recirculating air. If all the air is fresh air introduced from outside, that's mostly not a big deal (on an airplane, this is obviously less possible, due to outside conditions and the need to keep the cabin pressurized). Of course, this would be even more true if our outdoor air wasn't quite as polluted, which we *could* achieve, but don't seem to place a high priority on, except when we do, which is usually just as a lie to try and promote cars (you know, when they opposed the UPX because it was diesel, or when they try to justify widening roads, etc.).

The nice thing about straight ventilation vs. using HEPA filters is that the maintenance is much less critical to keeping the system working. If you aren't relying on expensive and frequently replaced filters, there's no opportunity for someone to cut the budget line and pull the filters...or to put it another way, passive systems are best.

Although re-circulation is also best for energy efficiency.