Section 172.3 - Applicability(a) This part applies to- (1) Each person who offers a hazardous material for transportation, and(2) Each carrier by air, highway, rail, or water who transports a hazardous material.(b) When a person, other than one of those provided for in paragraph (a) of this section, performs a packaging labeling or marking function required by this part, that person shall perform the function in accordance with this part.Amdt. 172-29, 41 FR 15996, 4/15/1976, as amended by Amdt. 172-32, 41 FR 38179, 9/9/1976