The responsibility for ensuring the right placards are on a vehicle transporting ammunition lies with the transportation company. They must comply with hazardous materials transportation regulations, and it is the driver's duty to ensure compliance before starting the journey.
It is the responsibility of the transportation company to ensure that the proper placards are displayed on a vehicle transporting ammunition. The transportation company is required to comply with regulations concerning the transportation of hazardous materials, which includes ammunition.
The driver of the truck, being an employee or operator for the transportation company, must follow the company's protocols and ensure that the vehicle is properly placarded before commencing the journey. While the owner and manufacturer of the ammunition have responsibilities regarding the safety and legality of their products, it is the transportation company, in the end, that must ensure the vehicle is correctly marked as per transportation laws.