33 CFR 151.41: Operating rules for oil-like NLS discharge

Last reviewed: October 14, 2026

This section sets operating requirements for oceangoing ships certificated under § 151.37(a) that carry oil-like NLS. The master or person in charge must ensure carriage and discharge meet the listed sections of this chapter. The oil-like NLS is not discharged unless both the monitor is set to detect it and a statement to that effect is entered in the Oil Record Book Part II (Cargo/Ballast Operations).

Applies toThe master or person in charge of an oceangoing ship certificated under § 151.37(a).

What it says

  1. The master or person in charge of an oceangoing ship certificated under § 151.37(a) must ensure that the requirements in paragraphs (a) and (b) are met.

    “The master or person in charge of an oceangoing ship certificated under § 151.37(a) shall ensure that—”

  2. The carriage and discharge of the oil-like NLS must meet §§ 157.29, 157.31, 157.35, 157.37, 157.41, 157.45, 157.47, and 157.49 of this chapter.

    33 CFR 151.41(a)“The carriage and discharge of the oil-like NLS meets §§ 157.29, 157.31, 157.35, 157.37, 157.41, 157.45, 157.47, and 157.49 of this chapter; and”

  3. The oil-like NLS must not be discharged unless both conditions in paragraphs (b)(1) and (b)(2) are met.

    33 CFR 151.41(b)“The oil-like NLS is not discharged unless—”

  4. One condition is that the monitor required by § 151.37(a)(1) is set to detect the oil-like NLS.

    33 CFR 151.41(b)(1)“The monitor required by § 151.37(a)(1) is set to detect the oil-like NLS; and”

  5. The other condition is that a statement that the monitor has been set to detect the oil-like NLS is entered in the Oil Record Book Part II (Cargo/Ballast Operations), required by § 151.25.

    33 CFR 151.41(b)(2)“A statement that the monitor has been set to detect the oil-like NLS is entered in the Oil Record Book Part II(Cargo/Ballast Operations), required by § 151.25.”

Common questions

Can I discharge an oil-like NLS if the monitor is not set to detect it?

No. The oil-like NLS is not discharged unless the monitor required by § 151.37(a)(1) is set to detect it, and the Oil Record Book statement is also entered.

“The monitor required by § 151.37(a)(1) is set to detect the oil-like NLS; and”

What must be recorded in the Oil Record Book before discharging oil-like NLS?

A statement that the monitor has been set to detect the oil-like NLS must be entered in the Oil Record Book Part II (Cargo/Ballast Operations), required by § 151.25.

“A statement that the monitor has been set to detect the oil-like NLS is entered in the Oil Record Book Part II(Cargo/Ballast Operations), required by § 151.25.”

Who must ensure these operating requirements are met?

The master or person in charge of an oceangoing ship certificated under § 151.37(a) must ensure they are met.

“The master or person in charge of an oceangoing ship certificated under § 151.37(a) shall ensure that—”

The text of 33 CFR 151.41

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

Operating requirements for oceangoing ships with IOPP Certificates: Category C and D Oil-like NLSs

The master or person in charge of an oceangoing ship certificated under § 151.37(a) shall ensure that—

(a) The carriage and discharge of the oil-like NLS meets §§ 157.29, 157.31, 157.35, 157.37, 157.41, 157.45, 157.47, and 157.49 of this chapter; and

(b) The oil-like NLS is not discharged unless—

(1) The monitor required by § 151.37(a)(1) is set to detect the oil-like NLS; and

(2) A statement that the monitor has been set to detect the oil-like NLS is entered in the Oil Record Book Part II(Cargo/Ballast Operations), required by § 151.25.

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.