IALA-B System

Aids To Navigation (ATONs) :   Along your way you may be able to find several types of navigation aids to assist you in avoiding dangers and shoals along with helping you to determine your position.  Navigation aids use color, shape and sound to assist in navigation.  When entering a harbor or going upstream in USA waters, red marks should pass on the starboard side and green marks should pass on the port side. Remember: Red Right Returning. Green marks have odd numbers and red marks have even numbers. The following navigation aids were found in "Hampton Roads," Virginia, USA.   

(This information applies to the IALA-B, International Association of Lighthouse Authorities - Region B Buoyage System, which is found in the Eastern Pacific, Atlantic and Pacific Coasts of North and South America, the Great Lakes, the Caribbean, Japan, Philippines and the Republic of Korea. Most of the rest of the world follows the IALA-A system (green right returning) which is found in the remainder of the Western Pacific, Indian Ocean, Atlantic Coasts of Africa and Europe, and the Mediterranean.)
Charts are for educational purposes only.  They do not contain recent updates.  Do not use for navigation !!!

Sounds:  Some buoys not only have lights but also sound to help you locate them. Bells and gongs are sounds which are associated with some buoys. All sounds are mechanically produced by wave motion. The ringing of a bell can be heard with minimal wave motion, gongs however require rough seas to generate the signal. The buoy to the right is green buoy #3. It has both a green light which flashes every 2.5 seconds and a bell which sounds as the waves move the buoy (Fl G 2.5s BELL). 
 

   View Chart - Red Arrow #7  -- 255 KB
  

Red daymarks are triangular in shape and have even numbers. The numbers are in order with the lowest numbers at the entrance of a channel or harbor and the highest numbers located deep within Hampton Harbor. The daymark on the right is red daymark #2. This is a lighted mark which flashes a red light every 4 seconds (Fl R 4s 15ft 3M). It is 15 feet tall and the light can be seen for three nautical miles on a clear night. Note the radio tower just above the landmark which can aid in localization of the mark while sailing and note the rocks whose position is approximate (Rks PA). View Chart - Red Arrow #1  -- 270 KB
 

 

Green daymarks have a square symbol and odd numbers. The green daymark to the right is at the bend of a channel leading to Hampton Harbor. It has a quick flashing green light and is 15 feet tall (Q G 15ft 3M). The light can be seen 3 nautical miles on a clear night. Note the two red daymarks "10" & "12" which mark the opposite side of the channel.
 View Chart - Red Arrow #2  -- 270 KB

 
Green daymarks are square shaped and have odd numbers. They should pass on the port side of the boat as you enter the harbor. To the right is green daymark #13. It is located at the entrance of Hampton Harbor.    Note the two ospreys perched on the daymark. Opposite this daymark is a red daymark "14" which marks the opposite side of the channel.
View Chart - Red Arrow #3  -- 270 KB

 


Preferred Channel Daymark:  This daymark is present at the junction of two channels. The color on the top indicates the side of the main or preferred channel. In the picture on the right, the daymark should pass to your port side (green on the top) to navigate in the preferred channel. This daymark is lighted with a flashing green light. Two flashes followed by one flash every six seconds.  The daymark "SC" is 15 feet tall and can be seen 3 nautical miles on a clear night (Fl (2+1) G 6s 15 ft 3M). View Chart - Red Arrow #PC  -- 270 KB



Red daymarks are triangular in shape and have even numbers. They should pass on the starboard side of the boat as you enter the harbor. To the right is red daymark #18 located deep in Hampton Harbor.
 View Chart - Red Arrow #4  -- 270 KB

 


The green buoy shown in the far right picture flashes a green light every 4 seconds (Fl G 4s). This buoy marks the east side of the channel leading from the sea south to Norfolk, VA. Past this buoy is the Norfolk Naval Base; while navigating these waters you must obey the naval security zones.

View Chart - Red Arrow #5  -- 255 KB

 


The red buoy shown in the far right picture flashes a red light every 2.5 seconds (Fl R 2.5s). This buoy marks the west side of the channel leading from the sea south to
Norfolk, VA.

View Chart - Red Arrow #6  -- 255 KB

 

Intracoastal Waterway:  The Intracoastal Waterway, which runs from New Jersey to Texas along the coast, cannot be defined in terms of "returning from sea."  For navigation aid purposes it is assumed that "returning from sea" is traveling the waterway in a clockwise fashion that is from New Jersey to Texas. In this direction red marks would be to the right (shoreward) and green to the left. There are exceptions when the Waterway runs opposite to the "returning from sea" direction of a channel. To avoid confusion all Intracoastal Waterway aids are uniquely identified with a yellow triangle or square. The triangle always marks the shoreward (normally red) side regardless of the color of the mark on which it appears.

The daymark shown on the right represents a mark serving as both a  channel and an ICW marker. It should be kept to PORT for vessels following the channel inland from the sea. However, it should be kept to STARBOARD for those vessels following the ICW from New Jersey to Texas (and kept to PORT for those traveling the ICW from Texas to New Jersey).