Who must comply?
First, where do you operate? If you go across state lines, that is known as “interstate commerce”, and you are subject to the Federal interstate rules. If you transport interstate freight, within one state, that is also “interstate commerce”. For example, you drive your tractor to the Port of Miami, pick up a container, and drive it to Tampa. Even though you did not leave the state of Florida, it is interstate commerce, and subject to the Federal rules, as that container originally came from a place outside the state of Florida, such as South America or something. Although you did not leave Florida, you are furthering an interstate movement of freight, making you subject to the interstate rules.
If you stay wholly within one State, and do not handle interstate freight, then you are subject to the safety regulations of that State. Most States have adopted the Federal regulations in their entirety. Others have adopted 95% of them, with a few exceptions. Generally speaking, the State safety regulations cannot be more stringent than the Federal rules. These means if you are following the Federal guidelines, you will be ok.
The Federal rules apply to anyone driving a vehicle with a Gross Vehicle Weight Rating of 10,001 pounds or more.
