Why should a driver avoid trying to identify an unknown hazardous material by smell if a leak is suspected?

Pick an answer

1. Some vapors are dangerous to inhale even in small amounts needed to detect a smell
2. It only matters if the material is confirmed to be flammable
3. This caution only applies once a leak is already heavy and visible
4. Smell is always a completely safe way to identify any leaking material nearby, no matter the type

Correct!

Not quite. The correct answer is highlighted.