A motor carrier may not transport in interstate or intrastate commerce any of the following hazardous materials, in the quantity indicated for each, unless the motor carrier holds a safety permit:

(a) A highway route-controlled quantity of a Class 7 (radioactive) material, as defined in §173.403 of this title;

(b) More than 25 kg (55 pounds) net weight of a Division 1.1, 1.2, or 1.3 (explosive) material or articles or an amount of a Division 1.5 (explosive) material requiring placarding under part 172 of this title;

(c) More than one liter (1.08 quarts) per package of a "material poisonous by inhalation," as defined in §171.8 of this title, that meets the criteria for "hazard zone A," as specified in §173.116(a) or §173.133(a) of this title;

(d) A "material poisonous by inhalation," in a "bulk packaging," both as defined in §171.8 of this title, that meets the criteria for "hazard zone B," as specified in §173.116(a) or §173.133(a);

(e) A "material poisonous by inhalation," as defined in §171.8 of this title, that meets the criteria for "hazard zone C," or "hazard zone D," as specified in §173.116(a) of this title, in a packaging having a capacity equal to or greater than 13,248 L (3,500) gallons; or

(f) A shipment of methane (compressed or refrigerated liquid), natural gas (compressed or refrigerated liquid), or any other compressed or refrigerated liquefied gas with a methane content of at least 85 percent, in bulk packaging having a capacity equal to or greater than 13,248 L (3,500 gallons).

[69 FR 39367, June 30, 2004, as amended at 77 FR 59826, Oct. 1, 2012; 80 FR 59073, Oct. 1, 2015; 84 FR 51433, Sept. 30, 2019]