46 CFR 143.230: Alarms and gauges on towing vessels

Last reviewed: October 14, 2026

This section requires each towing vessel to have a reliable means of notification for emergencies or essential system problems. It lists the alarms that must be provided, says how alarms must work, and lists the systems that must have gauges at the machinery location.

Applies toEach towing vessel.

What it says

  1. Each towing vessel must have a reliable means to provide notification when an emergency condition exists or an essential system develops problems that require attention.

    46 CFR 143.230(a)“Each towing vessel must have a reliable means to provide notification when an emergency condition exists or an essential system develops problems that require attention.”

  2. The vessel must have an alarm for low lubricating oil pressure on the auxiliary generator engine, among the alarms listed in paragraph (a).

    46 CFR 143.230(a)(3)“Auxiliary generator engine low lubricating oil pressure;”

  3. The vessel must have an alarm for low hydraulic steering fluid levels, if applicable.

    46 CFR 143.230(a)(6)“Low hydraulic steering fluid levels, if applicable; and”

  4. The vessel must have an alarm for low fuel level, if it is fitted with a day tank.

    46 CFR 143.230(a)(7)“Low fuel level, if fitted with a day tank.”

  5. Alarms may be a summary alarm at the operating station. If so, the specific alarm condition must be indicated at the machinery or bilge location.

    46 CFR 143.230(b)(1)“if the alarm at the operating station is a summary alarm, the specific alarm condition must be indicated at the machinery or bilge location;”

  6. Alarms must have a means to test actuation at each operating station, or the vessel must have a continuous self-monitoring alarm system that actuates if an alarm point fails or becomes disabled.

    46 CFR 143.230(b)(2)“Have a means to test actuation at each operating station or have a continuous self-monitoring alarm system which actuates if an alarm point fails or becomes disabled;”

  7. Alarms must not interfere with night vision at the operating station.

    46 CFR 143.230(b)(4)“Not interfere with night vision at the operating station.”

  8. The main engine lubricating oil pressure and main engine RPM systems must be equipped with gauges at the machinery location.

    46 CFR 143.230(c)(1)“Main engine lubricating oil pressure and main engine RPM;”

Common questions

Which alarms must a towing vessel have?

Paragraph (a) lists the alarms: main engine and auxiliary generator engine low lubricating oil pressure and high cooling water temperature, and high bilge levels. It also lists low hydraulic steering fluid levels, if applicable, and low fuel level, if fitted with a day tank.

“The following alarms must be provided:”

Can the alarm at the operating station be a summary alarm?

Yes, it may be a summary alarm. If it is, the specific alarm condition must be indicated at the machinery or bilge location.

“The alarm located at the operating station may be a summary alarm;”

How long must towing vessel alarms keep sounding?

Alarms must continue until they are acknowledged.

“Continue until they are acknowledged;”

The text of 46 CFR 143.230

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

Alarms and monitoring

(a) Each towing vessel must have a reliable means to provide notification when an emergency condition exists or an essential system develops problems that require attention. The following alarms must be provided:

(1) Main engine low lubricating oil pressure;

(2) Main engine high cooling water temperature;

(3) Auxiliary generator engine low lubricating oil pressure;

(4) Auxiliary generator engine high cooling water temperature;

(5) High bilge levels;

(6) Low hydraulic steering fluid levels, if applicable; and

(7) Low fuel level, if fitted with a day tank.

(b) Alarms must:

(1) Be visible and audible at each operating station. The alarm located at the operating station may be a summary alarm; if the alarm at the operating station is a summary alarm, the specific alarm condition must be indicated at the machinery or bilge location;

(2) Have a means to test actuation at each operating station or have a continuous self-monitoring alarm system which actuates if an alarm point fails or becomes disabled;

(3) Continue until they are acknowledged; and

(4) Not interfere with night vision at the operating station.

(c) The following systems must be equipped with gauges at the machinery location:

(1) Main engine lubricating oil pressure and main engine RPM;

(2) Main engine cooling water temperature;

(3) Auxiliary generator engine lubricating oil pressure and auxiliary generator engine RPM;

(4) Auxiliary generator engine cooling water temperature; and

(5) Hydraulic steering fluid pressure, if the vessel is equipped with hydraulic steering systems.

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.