105.20—Guidance and interpretations.

(a) Hazardous materials regulations. You can obtain information and answers to your questions on compliance with the hazardous materials regulations ( 49 CFR parts 171 through 180) and interpretations of those regulations by contacting PHMSA's Office of Hazardous Materials Safety as follows:
(b) Federal hazardous materials transportation law and preemption. You can obtain information and answers to your questions on Federal hazardous materials transportation law, 49 U.S.C. 5101 et seq., and Federal preemption of State, local, and Indian tribe hazardous material transportation requirements, by contacting PHMSA's Office of the Chief Counsel as follows:
[70 FR 56087, Sept. 23, 2005, as amended at 72 FR 55682, Oct. 1, 2007]