(1) The national regulations may prescribe requirements (the prescribed dimension requirements ) about the following—
(a) the dimensions of a heavy vehicle (together with its equipment);
(b) the dimensions of a component of a heavy vehicle;
(c) the dimensions of a heavy vehicle's load.
(2) Without limiting subsection (1), the prescribed dimension requirements may include requirements about the following—
(a) the dimensions of a heavy vehicle (together with its equipment) disregarding its load;
(b) the dimensions of a heavy vehicle together with its equipment and load;
(c) the dimensions by which a heavy vehicle's load projects from the vehicle;
(d) the internal measurements of a heavy vehicle, including, for example—
(i) the distance between components of the vehicle; and
(ii) for a combination, the distance between—
(A) the component vehicles of the combination; or
(B) a component vehicle of the combination and a component of another component vehicle of the combination.
(3) The national regulations may also prescribe requirements (that are not prescribed dimension requirements) about the use of a vehicle to which a dimension requirement applies, including, for example, requirements about the use of signs and warning devices.