Why are construction workers' warning vests yellow?

The first thing to say is that the warning vest of construction workers is not only yellow, but the common vest colors on site are mainly fluorescent yellow and fluorescent orange. Next, why are fluorescent yellow and orange?

1. The material of the reflective vest is composed of two major components: the fabric: fluorescent, which improves the visibility during the day. The standard is called the high-visibility warning reflective part: it reflects at night under the light, of course, it does not shine if it is not illuminated , To improve the visibility at night, not used during the day, but reduce the visibility, because the reflective strip is mainly gray, so it can not be too much, just appropriate. The reflective part also uses lattices. The expensive ones cannot be used, and the purchase cost is too high. China Railway Construction Corporation rarely uses them.

2. Why reflective vests are commonly used in fluorescent yellow and fluorescent orange red? Among red, orange, yellow, green, cyan, blue, and purple, the red light wave has the longest wave and the ability to penetrate the surrounding medium is the largest. Under the same luminosity condition, red is displayed farthest. In addition, red can remind people of dangerous information such as "fire" and "blood". The wavelength of yellow light is second only to red, and its position in the seven colors will also make people feel dangerous, and know that yellow light has the strongest ability to penetrate the medium fog. These two colors have strong visibility and can play a good warning role during the day and night; therefore, the construction workers' warning vests are generally fluorescent yellow and fluorescent orange red.