> My sister remembered the glowing handrails (radium?)

That reminded me of the "glowy tape" my brother and I used to play with when we were kids. It had come from my grandparents' estate, and we had no idea what it was for, but it was fun. My father thought it was from WWII, as he had vague memories of it being used to mark the corners of furniture during 'lights out' air raid drills. I now assume it was radium, and am not overly happy with my childhood self playing with it.