49 CFR §176.166

1. (a)Only the following Class 1 (explosive) materials may be transported as cargo on passenger vessels:
   1. (1)Division 1.4 (explosive) materials, compatibility group S.
   2. (2)Explosive articles designed for lifesaving purposes as identified in § 176.142(b)(2), if the total net explosive mass (weight) does not exceed 50 kg (110 pounds).
   3. (3)Class 1 (explosive) materials in compatibility groups C, D, and E, if the total net explosive mass (weight) does not exceed 10 kg (22 pounds) per vessel.
   4. (4)Articles in compatibility group G other than those requiring special stowage, if the total net explosive mass (weight) does not exceed 10 kg (22 pounds) per vessel.
   5. (5)Articles in compatibility group B, if the total net explosive mass (weight) does not exceed 5 kg (11 pounds).
2. (b)Class 1 (explosive) materials which may be carried on passenger vessels are identified in column (10) of the § 172.101 table. They must be stowed in accordance with table 176.166(b).
3. (c)Notwithstanding the provisions of paragraph (a) of this section, a combination of the substances and articles listed in paragraphs (a)(1) through (a)(5) of this section may be transported on the same passenger vessel provided the total net explosive mass (weight) of the combination of Class 1 (explosive) materials carried does not exceed the smallest quantity specified for any one of the substances or articles in the combination.