Five and a half hours after understanding why incandescent lights are only 2% efficient, I now know why traffic lights are blue! (The other four colours being yellow, red, white, and black of course)
Wikipedia is terrible and unreliable and no one should use it since it allows anonymous editing. And apparently, fluorescent lighting is known to give people headaches and much worse but mixing lighting types even more so.
The whole concept of lighting temperatures or matching film type to spectral behavior of lighting is probably unfamiliar to many people using a display medium that does not depend on ambient lighting. Browser history 177 pages, all in the Wikimedia namespace or linked sites ._. Don't feel like talking about it