Mobile unit means a vehicle specifically authorized under a RIN to carry out requalification operations identified under the RIN within specified geographic areas away from the principle place of business. Mobile units must comply with the requirements outlined in the approval issuance letter from the Associate Administrator for Hazardous Materials Safety (see 107.805 of subchapter A of this chapter).
49 CFR § 180.203
As used in this section, the word cylinder includes UN pressure receptacles. In addition to the definitions contained in 171.8 of this subchapter, the following definitions apply to this subpart: