Why must placards be visible from all four sides of a vehicle?

Pick an answer

1. It's only a manufacturer style preference with no safety reasoning behind where placards get mounted
2. Only the front of the vehicle is required to carry a placard
3. Visibility from the sides matters only after dark
4. So responders and other drivers can identify the hazard no matter which direction they approach from

Correct!

Not quite. The correct answer is highlighted.