He also did an interview with a person from the NIMH who personally only uses candle light past dark. It makes sense when you think about it.
Also apparently overhead lights are worse- the angle makes a difference.
Also apparently overhead lights are worse- the angle makes a difference.
Yes, there's an angle component that's a bit concerning as well. It seems that our eyes mostly respond to the blues "above the horizon" - which makes sense given how our world works. Blue on the ground isn't interesting, nor bright, and our bodies don't tend to waste energy building things where they're not useful.
It does imply that our overhead lighting (most homes have overhead lighting in some forms or another) is more concerning than we've broadly considered - screens in the line of sight are important if bright, but the overhead lighting is hitting more of the relevant cells.
However, most of the lanterns (think your standard "hurricane lantern" or "cold blast lantern") are quite clean burning. I've been using lanterns for a while now, and I have the equipment to measure PM2.5 and PM10 (post author here, you can find reviews of my lanterns and my particulate sensors elsewhere on my blog).
The lanterns are "basically zero" in terms of PM2.5 and PM10 in the exhaust stream, and when you dig into papers talking about kerosene lighting and particulates, they come to the same conclusions - most of the particulate is from the open flame kerosene burners, not the actual lanterns.
I use lanterns in my office in the winter for some extra heat (I'm the "solar shed" guy, winter sucks during inversions), and I see a fairly rapid rise in CO2 levels (about like another 2-3 people in my space), but I don't see high PM2.5 unless I've got an actual open flame candle going.
I went through a period where as soon as I got home and out of the shower I’d go dark. I had a battery powered lamp that I used exclusively. I’d wear an eye mask with something to listen to playing. It definitely helped. I can definitely feel blue light waking me up much more easily than red. (Worked swing shift until midnight at that point.)
Blue light(instead of just lumens) has much less evidence.