Rules of the Road & Aids to Navigation (ATONS) as applied to Narragansett Bay

Better Bay Alliance (BBA)
February 2023


  • Learn the purpose of “Rules”
  • Learn Navigational terms
  • Learn to interpret navigation lights
  • Learn the basic Inland Navigation Rules for crossing, meeting & overtaking situations
  • Learn the “Pecking Order” for vessels

Navigation Rules: “The Rules of the Road”

Who wrote the rules?

Navigation Rules” are published by the U.S. Department of Homeland Security for the United States Coast Guard.

Updated copies can be downloaded online at:

Rules of the Road

What do the Rules do?

If followed, they protect against loss of life, injury, and property damage as a result of collision. Prevent Accidents!

Most Collisions Could Be Avoided By…

  • Practicing the “Rules of the Road”
    Rule 1
  • Use of a “proper lookout”
    Rule 5
  • Maintaining safe speed
    Rule 6
  • Displaying proper lights
    Rule 20
  • Knowing the “Aids to Navigation”
Rules of the Road

Ground Rules for Navigation

Responsibility & Definitions
General Definitions
Underway Not at anchor or made fast to the shore or aground
Right-of-way The right and duty to maintain course and speed
Stand-On Vessel Vessel that has the right of way
Give Way Vessel Must keep clear of the stand-on vessel
Short Blast A blast of approximately 1 second
Prolonged Blast A blast of 4 to 6 seconds

“Safe Speed” Definition

Speed that allows proper and effective action to avoid collision based on the following factors:

  • Visibility
  • Traffic density and characteristics
  • Maneuverability, draft
  • Background clutter
  • Weather, wind, current, navigational hazards

Encountering Other Vessels

Rule 13 – Overtaking

Vessel that is passed by another from a position more than 22.5 degrees abaft of it’s beam is the stand-on vessel. The give-way vessel should not see the green or red navigation sidelights. If in doubt whether overtaking or crossing, always assume overtaking.

Give-way vessel will keep clear of stand-on vessel until finally well past and clear.

But be careful! White light only could also indicate a vessel sailing or a vessel at anchor or under oars.

Rules of the Road

Rule 14 – Head On

When two power-driven vessels are on reciprocal courses, vessels will steer to starboard so each shall pass port to port of each other. At night, vessels in a head-on situation should observe masthead light(s) in a line and one or both sidelights.

Rules of the Road

Rule 15 – Crossing

A vessel which has another vessel on her starboard side shall keep out of the way of the other and if necessary, avoid crossing ahead of the other vessel. Easy way to remember this is vessel to the right “has rights”! Once you learn this, you’ll also recognize it’s consistent with the red/green light scheme.

Rules of the Road

It is important to remember that within the COLREGS, the STAND ON (right of way) vessel must potentially alter course or speed to avoid a collision! Don’t forget many boaters don’t know the Rules of the Road.

Rule 18- Responsibilities Between Vessels (Inland)

Pecking Order


  1. Not under command (NUC)
  2. Restricted in ability to maneuver (RAM) (dredging, mine sweeping, car carriers)
  3. Fishing/trawling (not trolling)
  4. Sail or manually powered boat
  5. Power-driven
  6. Seaplane


Navigation Lights and Shapes (Rules 20 – 31)

White Light

360 degree light
required when anchored

Red and Green Lights

112.5 degree arc = 90+22.5
Required when underway between sunset and sunrise or in restricted visibility

Rules 20 Thru 31 – Lights and Shapes

Rules of the Road

Rules 34 Maneuvering and Warning

Inland – Signals of intent with appropriate reply required.
Inland Rules require the other vessel to answer with the same signal if in agreement.
One short
I intend to pass you on my port side
x 2
Two short
I intend to pass you on my starboard side
x 3
Three short
I am operating astern (reverse) propulsion
x 5
Five short
Danger, I do not understand, I disagree