Popular Science, lokakuu 1946
Better radiation, and consequently more heat, can be coaxed from your radiators this winter by repainring with flat wall paint. A bulletin from the National Bureau of Standards states that nonmetallic flat paint is 16 2/3 percent more effective on radiators than metallic paints such as bronze or aluminum. And to make it easier, so you won't have to scrape off old paint, only the top coat influences radiation.
The color of the paint also has its effect on heating efficiency, with white giving off most heat. Cream, red, gray, yellow, black, aluminum (color only), and brown then follow in the order named.