If the words "Inhalation Hazard" appear on shipping papers:

1. An inhalation hazard placard must be used, but only if more than 100 pounds of the material are being transported.
2. An inhalation hazard placard must always be used.
3. An inhalation hazard placard does not need to be used in intrastate commerce.
4. An inhalation hazard placard must be used, but only if the vehicle is traveling across state lines.