Developed as a set of standards, by the United Nations, Un ratings are essential for shipping or storing hazardous materials. The Un Rating is a series of number and letter codes that show what a container is regulated to handle. They determine this through a series of tests that all containers must undergo if they are to be UN Rated. Current UN Regulations are enforced by the D.O.T. It is up to the manufacturer of the product to determine what Un Rating they need.