33 CFR 155.480: Overfill devices on tank vessel cargo tanks

Last reviewed: October 14, 2026

This section requires certain tank vessels to have an overfill device permanently installed on each cargo tank. It sets device standards for tankships and tank barges and deadlines for U.S. flag and foreign flag vessels. It lists vessels it does not apply to.

Applies toEach tank vessel with a cargo capacity of 1,000 or more cubic meters (approximately 6,290 barrels), loading oil or oil residue as cargo.

What it says

  1. Each tank vessel with a cargo capacity of 1,000 or more cubic meters (approximately 6,290 barrels) that loads oil or oil residue as cargo must have one permanently installed overfill device on each cargo tank.

    33 CFR 155.480(b)“must have one overfill device that is permanently installed on each cargo tank and meets the requirements of this section.”

  2. On a tankship, each cargo tank must have an overfill device, including an independent audible alarm or visible indicator for that tank, that meets the tank overfill alarm requirements under 46 CFR 39.20-7(b)(2) and (3), and (d)(1) through (d)(4).

    33 CFR 155.480(b)(1)“each cargo tank must be equipped with an overfill device (including an independent audible alarm or visible indicator for that tank)”

  3. On a tank barge, each cargo tank must have an overfill device that meets one of three options, listed in paragraphs (b)(2)(i) through (iii).

    33 CFR 155.480(b)(2)“On a tank barge, each cargo tank must be equipped with an overfill device that—”

  4. One tank barge option is an installed automatic shutdown system that meets the requirements of 46 CFR 39.2009(a)(2).

    33 CFR 155.480(b)(2)(ii)“Is an installed automatic shutdown system that meets the requirements of 46 CFR 39.2009(a)(2); or”

  5. Each cargo tank of a U.S. flag tank vessel must have the overfill device installed at the next scheduled cargo tank internal examination performed under 46 CFR 31.10-21.

    33 CFR 155.480(c)“at the next scheduled cargo tank internal examination performed on the vessel under 46 CFR 31.10-21.”

  6. Each cargo tank of a foreign flag tank vessel must have the overfill device installed at the first survey that includes dry docking, as its flag administration requires, or at the first cargo tank internal examination under 46 CFR 31.10-21.

    33 CFR 155.480(d)(2)“At the first cargo tank internal examination performed on the tank vessel under 46 CFR 31.10-21.”

  7. This section does not apply to tank vessels that carry asphalt, animal fat, or vegetable oil as their only cargo.

    33 CFR 155.480(f)“This section does not apply to tank vessels that carry asphalt, animal fat, or vegetable oil as their only cargo.”

Common questions

Which tank vessels need an overfill device?

Each tank vessel with a cargo capacity of 1,000 or more cubic meters (approximately 6,290 barrels) that loads oil or oil residue as cargo needs one on each cargo tank.

“Each tank vessel with a cargo capacity of 1,000 or more cubic meters (approximately 6,290 barrels), loading oil or oil residue as cargo”

When must a U.S. flag tank vessel install overfill devices?

It must install them at the next scheduled cargo tank internal examination performed under 46 CFR 31.10-21.

“at the next scheduled cargo tank internal examination performed on the vessel under 46 CFR 31.10-21.”

Are tank vessels carrying only vegetable oil exempt from the overfill device rule?

Yes. This section does not apply to tank vessels that carry asphalt, animal fat, or vegetable oil as their only cargo.

“This section does not apply to tank vessels that carry asphalt, animal fat, or vegetable oil as their only cargo.”

The text of 33 CFR 155.480

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Overfill devices

(a) For the purposes of this section, “oil” has the same definition as provided in § 151.05 of this chapter.

(b) Each tank vessel with a cargo capacity of 1,000 or more cubic meters (approximately 6,290 barrels), loading oil or oil residue as cargo, must have one overfill device that is permanently installed on each cargo tank and meets the requirements of this section.

(1) On a tankship, each cargo tank must be equipped with an overfill device (including an independent audible alarm or visible indicator for that tank) that meets the requirements for tank overfill alarms under 46 CFR 39.20-7(b)(2) and (3), and (d)(1) through (d)(4).

(2) On a tank barge, each cargo tank must be equipped with an overfill device that—

(i) Meets the requirements of 46 CFR 39.2007(b)(2) through (b)(4), (d)(1) through (d)(4), and 46 CFR 39.2009(a)(1) ;

(ii) Is an installed automatic shutdown system that meets the requirements of 46 CFR 39.2009(a)(2); or

(iii) Is an installed high-level indicating device that meets the requirements of 46 CFR 39.2003(b)(1), (2), and (3).

(c) Each cargo tank of a U.S. flag tank vessel must have installed on it an overfill device meeting the requirements of this section at the next scheduled cargo tank internal examination performed on the vessel under 46 CFR 31.10-21.

(d) Each cargo tank of a foreign flag tank vessel must have installed on it an overfill device—

(1) At the first survey that includes dry docking, as required by the vessel's flag administration, to meet the International Convention for the Safety of Life at Sea (SOLAS), 1974, as amended, or the International Load Line Convention of 1966; or

(2) At the first cargo tank internal examination performed on the tank vessel under 46 CFR 31.10-21.

(e) This section does not apply to a tank vessel that does not meet the double hull requirements of § 157.10d of this chapter and, under 46 U.S.C. 3703a(c), may not operate in the navigable waters or Exclusive Economic Zone of the United States after January 1, 2000.

(f) This section does not apply to tank vessels that carry asphalt, animal fat, or vegetable oil as their only cargo.

Sections it refers to

The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.