Red is a very stimulating color and it will most of the time gain your attention. Having people associate danger with the color red could be useful as it would be the first thing people notice and allow them to react.
because the wavelength of red is the highest!
usually red but can be others
there are mostly yellow.
Yellow
Caution and warning, in general.
Purple, like the beverage
US standard traffic warning signs are yellow background with black symbols or letters. Traffic warning signs in other countries are generally white or yellow background with a red or black border in a triangular shape. Industrial warning signs are various colors, including OSHA and ANZI standards with orange background and black lettering. A yellow OSHA or ANZI sign would mean "caution" not "warning".
One of the first warning signals of bladder cancer is blood in the urine. Sometimes, there is enough blood to change the color of the urine to a yellow-red or a dark red.
warning
Without know what the warning light say's, all I can tell you in Yellow means caution.
Rafa's favorite color is yellow.
The colors on a stop light are red, green, and yellow. On the stoplight, red is the top color, yellow is the middle, and green is on the bottom. Green means go, red means stop, and yellow is a warning that red is coming.
yellow
An yellow color, from sodium