(a) The requirements of this section apply to all tank barges carrying those cargoes listed on table 30.25-1, of this subchapter, which are defined as:

(1) Flammable liquids having a Reid vapor pressure in excess of 25 pounds per square inch, absolute, in independent tanks (part 32 of this subchapter).

(2) Liquefied flammable gases (part 38 of this subchapter).

(b) All tank barges constructed or modified in conformance with the requirements of subpart 32.63 of this subchapter are exempt from the provisions of § 35.01-45.

(c) When it is necessary to operate box or square-end barges as lead barges of tows, the Person in Charge of the towing vessel must control the speed to ensure protection against diving and swamping of such barges, having due regard to their design and freeboard, and to the operating conditions.

(d) All barges, while carrying in bulk any of the cargoes described in paragraph (a) of this section, must be operated in conformance with the provisions of this section. However, the provisions of this section are not applicable to such barges when empty and gas-freed.

(e) Barges must not be moved from a loading facility unless all bilges and void spaces (except those used for ballasting) are substantially free of water. Periodic inspections and necessary pumping must be carried out to ensure maintenance of such water-free condition in order to minimize the free surface effects, both in the longitudinal and transverse directions. Except when otherwise considered necessary for inspection or pumping, all hatch covers and other hull closure devices for void spaces and hull compartments other than cargo spaces must be closed and secured at all times.

(f) During the time the cargo tanks contain dangerous cargoes described in paragraph (a) of this section in any amount, in the liquid or gaseous state, the barge must be under constant surveillance.

(1) A strict watch of each unmanned barge in tow must be maintained from the towing vessel while underway.

(2) A towing vessel engaged in transporting such unmanned barges must not leave them unattended. When a barge is moored, but not gas free, it must be under the observation of a watchman who may be a member of the complement of the towing vessel, or a terminal employee, or other person. Such person will be responsible for the security of the barge and for keeping unauthorized persons off the barge.

(g) The owner, operator, Master, or Person in Charge of any barge carrying dangerous cargoes described in paragraph (a) of this section must ensure that, while the barge is being towed, and during cargo transfer operations, the persons as required by § 31.15-5 of this subchapter and § 35.35-1 are provided.