The Meaning of these Signals..Really Funny Meaning Manipulations..

This is due to the weather, as it is easier to see a red/amber sign in the snowy weather than a red/white sign. The polar bear warning sign in Svalbard recently changed from displaying a black bear on white background to a white bear on black background (both signs are triangular with a red border).

Some countries that normally use a white background have adopted an orange or amber background for road work or construction signs.

Warning signs in some countries have a diamond shape in place of the standard triangular shape. In the United States, Canada, Mexico, Thailand, Australia, Japan, Philippines, Indonesia, Malaysia and New Zealand warning signs are black on a yellow background and usually diamond-shaped, while temporary signs (which are typically construction signs) are black on an orange background.

Ireland also adopted these standards, diverging from the standards of the rest of Europe. Some other countries also use these standards for some signage.

A general warning signs are used in instances in which the particular hazard, obstacle or condition is not covered by a standard sign. In Europe, they usually comprise an exclamation mark on the standard triangular sign with an auxiliary sign below in the local language identifying the hazard, obstacle or condition.

In countries using diamond-shaped signs, the explanatory language is written directly on the diamond-shaped sign, although it may contain only a general warning such as “Caution”, and pictograms may also be used as it has been initiated at first in Quebec.

Diamond-shaped with reflectors are placed at point of curbs, dividers, or other lane obstacles. Rectangular signs with diagonal stripes indicate solid objects such as barricades, bridge abutments, utility poles or natural obstacles near the roadway.

Left side obstacles are marked with stripes running high to low, left to right; right side obstacle signs use stripes running high to low, right to left; in a sense akin to International symbol of arrow pointing down toward side toward roadway.
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