(a) Each barge engaged in cleaning operations at an approved cleaning facility must have a conductive fixed stripping line installed in each cargo tank. The line must extend to the low point of each cargo tank, extend through and be welded to the top of the cargo tank, and terminate above deck with a full port valve plugged at the open end.

(b) An existing fixed stripping system may be used instead of the stripping line required in paragraph (a) of this section.

(c) Each stripping line must be labeled at an on-deck location with the words “Stripping Line-Tank” followed by the tank's number, name, or location.

(d) Vapors may be collected from the barge's cargo tanks through a common fixed vapor header, through the fixed liquid cargo header, or through flanged flexible hoses located at the top of each cargo tank.

(e) The vapor collection system must not interfere with the proper operation of the cargo tank venting system.

(f) A barge being gas-freed by a fluid displacement system must fulfill the following requirements:

(1) If the fluid medium is a compressible fluid, such as inert gas, it must be injected into the barge's cargo tanks through a common fixed vapor header, through the fixed liquid cargo header, or through a flexible hoses flanged to a connection located at the top of each cargo tank;

(2) If the fluid medium is a non-compressible fluid, such as water, it must be injected into the barge's cargo tanks through the fixed liquid cargo header only; and

(3) If the fluid medium is a non-compressible fluid, such as water, the barge must be equipped with a liquid overfill protection arrangement and fulfill the requirements for tank barge liquid overfill protection contained in 46 CFR 39.2009.

(g) The barge vapor connection must be electrically insulated from the facility vapor connection and the fluid injection connection must be electrically insulated from the fluid injection source, if fitted, in accordance with OCIMF ISGOTT section 17.5 (incorporated by reference, see 46 CFR 39.1005).

(h) Vapor collection piping must be electrically bonded to the barge hull and must be electrically continuous.

(i) All equipment used on the barge during cleaning operations must be electrically bonded to the barge and tested to ensure electrical continuity prior to each use.

(j) Hoses used for the transfer of vapors during cleaning operations must meet the requirements of 46 CFR 39.2001(i) and have markings as required in 46 CFR 39.2001(h).

(k) Hoses used for the transfer of liquids during cleaning operations must—

(1) Have a designed burst pressure of at least 600 pounds per square inch gauge (psig);

(2) Have a maximum allowable working pressure of at least 150 psig;

(3) Be capable of withstanding at least the maximum vacuum rating of the cleaning facility's vapor-moving device without collapsing or constricting;

(4) Be electrically continuous with a maximum resistance of 10,000 ohms;

(5) Have flanges with a bolthole arrangement complying with the requirements for 150 pound class ANSI B16.5 flanges (incorporated by reference, see 46 CFR 39.1005); and

(6) Be abrasion and kinking resistant and compatible with the liquids being transferred.

(l) If a hose is used to transfer either vapor or liquid from the barge during cleaning operations, hose saddles that provide adequate support to prevent the collapse or kinking of hoses must accompany hose handling equipment.

(a) The volumetric flow rates during stripping or gas-freeing operations must be limited within a range such that the cargo tank venting system required by 46 CFR 32.55 will keep the cargo tank within its maximum design working pressure or the maximum design vacuum.

(b) Each barge must be fitted with a means for connecting the pressure-sensing and pressure-indicating devices required by 33 CFR 154.2203(g) and (o) on each cargo tank top, or on the common vapor header provided that pressures measured by the devices are adjusted to compensate for the pressure drop across the vapor piping from the cargo tank to the devices. The valve for the connection point must be labeled “Pressure Sensor/indicator Connection.”

(c) For stripping operations with closed cargo tanks, the maximum stripping rate must not exceed the volumetric flow capacity of the vacuum relief valve protecting the cargo tank.

(a) The following inspections must be conducted by the barge person in charge prior to commencing gas-freeing operations, and show that—

(1) Each part of the barge's vapor collection system is aligned to allow vapor to flow to a cleaning facility's vapor control system (VCS);

(2) If a fluid displacement system is used to conduct gas-freeing operations—

(i) The fluid supply line is connected to the fluid injection connection; and

(ii) The maximum fluid injection rate is determined in accordance with 46 CFR 39.6007(c)(2);

(3) The maximum stripping or gas-freeing rate is determined in accordance with 46 CFR 39.6003(c) or 39.6007(c), respectively, and adequate openings required by 46 CFR 39.6007(c)(1) are available and identified;

(4) The pressure-sensing and pressure-indicating devices required by 33 CFR 154.2203 are connected as required by 46 CFR 39.6003(b);

(5) The maximum and minimum operating pressures of the barge being cleaned are determined;

(6) Unrepaired loose covers, kinks, bulges, gouges, cuts, slashes, soft spots, or any other defects which would permit the discharge of vapors through the vapor recovery hose material must be detected during inspection and repaired prior to operation;

(7) The facility vapor connection is electrically insulated from the barge vapor connection and the fluid injection connection is electrically insulated from the fluid injection source, if fitted, in accordance with OCIMF ISGOTT section 17.5 (incorporated by reference, see 46 CFR 39.1005); and

(8) All equipment is bonded in accordance with 46 CFR 39.6001(h).

(a) During cleaning operations, vapors from a tank barge cannot be transferred to a cleaning facility which does not have a marine vapor control system (VCS) certified by a certifying entity, and its facility operations manual endorsed by the Captain of the Port (COTP) as meeting the requirements of 33 CFR part 154, subpart P.

(b) Prior to commencing stripping operations, the maximum allowable stripping rate must be determined. The maximum allowable stripping rate must not exceed the volumetric flow capacity of the vacuum relief valve protecting the cargo tank.

(c) The maximum gas-freeing rate is determined by the following:

(1) For a vacuum displacement system—

(i) The maximum allowable gas-freeing rate is a function of the area open to the atmosphere for the cargo tank being gas-freed. The area open to the atmosphere must be large enough to maintain the pressure in the cargo tank being gas-freed at or above 14.5 pounds per square inch absolute (psia) (−0.2 pounds per square inch gauge (psig));

(ii) The maximum allowable gas-freeing rate must be calculated from Table 1 of this section, using the area open to the atmosphere for the cargo tank being gas-freed as the entering determination;

(2) For a fluid displacement system, the maximum allowable gas-freeing rate is determined by the lesser of the following:

(i) Eighty percent of the total venting capacity of the pressure relief valve in the cargo tank venting system when relieving at its set pressure;

(ii) Eighty percent of the total vacuum relieving capacity of the vacuum relief valve in the cargo tank venting system when relieving at its set pressure; or

(iii) The rate based on pressure drop calculations at which, for a given pressure at the facility vapor connection, the pressure in the cargo tank being gas-freed exceeds 80 percent of the setting of any pressure relief valve in the cargo tank venting system.

(d) Any hatch and/or fitting used to calculate the minimum area required to be open to the atmosphere must be opened and secured in such a manner as to prevent accidental closure during gas freeing. All flame screens for the hatch and/or fitting opened must be removed in order to allow for maximum airflow. The hatch and/or fitting must be secured open before the pressure in the cargo tank falls below 10 percent of the highest setting of any of the barge's vacuum relief valves.

(e) “Do Not Close Hatch/Fitting” signs must be conspicuously posted near the hatch and/or fitting opened during gas-freeing operations.

(f) To minimize the dangers of static electricity, all equipment used on the barge during gas-freeing and cleaning operations must be electrically bonded to the barge and tested to ensure electrical continuity before each use.

(g) If the barge is equipped with an inert gas system, the inert gas main isolation valve must remain closed during cleaning operations.

(h) Vapors from incompatible cargoes that are collected simultaneously must be kept separated throughout the barge's entire vapor collection system. Chemical compatibility must be determined in accordance with the procedures contained in 46 CFR part 150, part A.

The designation and qualification requirements contained in 33 CFR 155.700 and 33 CFR 155.710(a)(2) apply to the barge person in charge.