31540.  (a) The department shall adopt and enforce such regulations
as it determines are necessary for public safety regarding the
transportation of:
   (1) Freight van or tank containers which can be removed from the
running gear or chassis of a truck or trailer, and
   (2) Collapsible containers used to transport liquids on flatbed
vehicles.
   (b) It is unlawful to fail to comply with any provision of the
regulations adopted by the department.