33 CFR 155.120: Equivalents to oil pollution prevention equipment
Last reviewed: October 14, 2026
This section lets the Commandant allow alternative fittings, materials, appliances or apparatus on request, if they are at least as effective as those required. It covers ships surveyed under § 151.17 and tank vessels needing overfill devices. Operational methods cannot replace required design and construction features.
Applies toShips required to be surveyed under § 151.17 of this chapter, and tank vessels required to have overfill devices installed under parts 155 and 156 of this chapter.
What it says
For ships required to be surveyed under § 151.17 of this chapter, the Commandant may, on written request, allow an alternative fitting, material, appliance or apparatus if it is at least as effective as that required by subpart B.
33 CFR 155.120(a)“the Commandant may, upon receipt of a written request, allow any fitting, material, appliance or apparatus to be fitted in a ship as an alternative”
The alternative must be at least as effective as what subpart B requires.
33 CFR 155.120(a)“if such fitting, material, appliance, or apparatus is at least as effective as that required by subpart B”
Operational methods to control oil discharge are not allowed in place of design and construction features prescribed by both MARPOL 73/78 and subpart B of this part.
33 CFR 155.120(a)“Substitution of operational methods to control the discharge of oil in place of those design and construction features prescribed by MARPOL 73/78 that are also prescribed by subpart B of this part is not allowed.”
An equivalent authorized for a ship having an IOPP Certificate is noted on that Certificate.
33 CFR 155.120(b)“Any equivalent to a feature prescribed by MARPOL 73/78 that is authorized for a ship having an IOPP Certificate is noted on that Certificate.”
For tank vessels required to have overfill devices under parts 155 and 156 of this chapter, the Commandant may, on written request, allow an alternative to the required overfill device if it is at least as effective as that required in the regulations.
33 CFR 155.120(c)“if the proposed alternative device is at least as effective as that required in the regulations”
Common questions
Can the Coast Guard approve an alternative to a required overfill device?
Yes. The Commandant may, on written request, allow an alternative to the required overfill devices if the proposed device is at least as effective as that required in the regulations.
“if the proposed alternative device is at least as effective as that required in the regulations”
Can operational methods replace required oil discharge design features?
No. Substituting operational methods for design and construction features prescribed by MARPOL 73/78 that are also prescribed by subpart B of this part is not allowed.
“Substitution of operational methods to control the discharge of oil in place of those design and construction features prescribed by MARPOL 73/78 that are also prescribed by subpart B of this part is not allowed.”
Where is an approved equivalent recorded for a ship with an IOPP Certificate?
An authorized equivalent to a MARPOL 73/78 feature is noted on the ship's IOPP Certificate.
“Any equivalent to a feature prescribed by MARPOL 73/78 that is authorized for a ship having an IOPP Certificate is noted on that Certificate.”
The text of 33 CFR 155.120
Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR
Equivalents
(a) For ships required to be surveyed under § 151.17 of this chapter, the Commandant may, upon receipt of a written request, allow any fitting, material, appliance or apparatus to be fitted in a ship as an alternative to that required by both MARPOL 73/78 and subpart B of this part if such fitting, material, appliance, or apparatus is at least as effective as that required by subpart B. Substitution of operational methods to control the discharge of oil in place of those design and construction features prescribed by MARPOL 73/78 that are also prescribed by subpart B of this part is not allowed.
(b) Any equivalent to a feature prescribed by MARPOL 73/78 that is authorized for a ship having an IOPP Certificate is noted on that Certificate.
(c) For tank vessels required to have overfill devices installed under parts 155 and 156 of this chapter, the Commandant may, upon receipt of a written request, allow any fitting, material, appliance, or apparatus to be fitted in a tank vessel as an alternative to the required overfill device(s) that are specified in these parts if the proposed alternative device is at least as effective as that required in the regulations.
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.