Lateral Markers: Colors And Numbers - Boat Ed

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Course Outline

  • Unit 1: Before Getting Underway
    • Topic 1: The Many Parts of a Boat
      • Parts of a Boat From a Side View
      • Parts of a Boat From a Front View
      • Activity: Can You Label the Parts of a Boat?
    • Topic 2: Types of Boat Hulls
      • Displacement Hulls
      • Planing Hulls
      • How Planing Hulls Operate
      • Descriptions of Hull Shapes
    • Topic 3: Boat Length
      • Measuring Length Overall
      • Length Classes
      • Video: Boat Lengths and Hull Types
    • Topic 4: Types of Engines and Drives
      • Outboard Engines
      • Inboard Engines
      • Stern Drives
      • Jet Drives
    • Topic 5: Personal Watercraft (PWCs)
      • What Is a Personal Watercraft?
      • Parts of a PWC From a Front View
      • Parts of a PWC From a Side View
    • Topic 6: Sailboats
      • Parts of a Sailboat
    • Topic 7: Your Boat's Capacity
      • The Capacity Plate
      • Example of a Capacity Plate
      • Calculating Your Boat's Capacity
      • Video: Boat Capacity
    • Topic 8: Float Plans
      • Filing a Float Plan
      • Float Plan for Short Outings
      • Float Plan for Extended Outings
      • Video: Float Plan
  • Unit 2: Getting Out on the Water
    • Topic 1: Casting Off
      • Before Casting Off
      • Casting Off With No Wind or Current
      • Activity: Casting Off With Wind or Current Toward the Dock
      • Activity: Casting Off With Wind or Current Away From the Dock
      • Video: Casting Off
    • Topic 2: Docking
      • Before Docking
      • Activity: Docking With No Wind or Current
      • Activity: Docking With Wind or Current Toward the Dock
      • Activity: Docking With Wind or Current Away From the Dock
      • Video: Docking
    • Topic 3: Navigation Rules: Traffic Laws of the Waterways
      • Three Major Responsibilities of Every Boater
      • Rules for Encountering Other Vessels
      • Exceptions to the Navigation Rules
      • Navigation Rules Definitions
      • Video: Navigation Rules - Traffic Laws of the Waterways
      • Power-Driven Vessel Encountering Power-Driven Vessel
      • Power-Driven Vessel Encountering Sailing Vessel
      • Sailing Vessel Encountering Sailing Vessel
      • Responsibilities Between Vessels
      • Video: Encountering Other Vessels
      • Operating During Restricted Visibility
      • Additional Information About Navigation Rules
    • Topic 4: Navigation Lights
      • Common Navigation Lights
      • Animation: Common Navigation Lights
      • Typical Recreation Vessels' Navigation Lights
      • Video: Night Navigation Lights
    • Topic 5: Night Navigation
      • Challenges of Navigating at Night
      • In a Power-Driven Vessel: If You See a Green and a White Light
      • In a Power-Driven Vessel: If You See Only a White Light
      • In a Power-Driven Vessel: If You See a Red and a White Light
      • In a Power-Driven Vessel: If You See a Red, a Green, and a White Light
      • In Any Type of Vessel: If You See a Red and a Green Light but No White Light
      • In Any Type of Vessel: If You See Only a Green Light or Only a Red Light
      • Video: Night Navigation
      • Towing Lights on Commercial Vessels
    • Topic 6: Sound Signals
      • Sound Signals Used for Encountering Situations
      • Examples of Sound Signals Used for Encountering Situations
      • Sound Signals Used to Alert or Warn
  • Unit 3: Navigation and Safe Operation
    • Topic 1: U.S. Aids to Navigation System (ATON)
      • Traffic Signals of the Waterways
      • Video: Navigation Aids
      • Lateral Markers: Colors and Numbers
      • Lateral Markers: Shapes
      • Lateral Markers: Other Kinds of Buoys and Markers
      • Lateral Markers: "Red Right Returning"
      • Video: Intracoastal Waterway
      • Western Rivers System
      • Non-Lateral Markers
      • Common Non-Lateral Markers
      • Other Non-Lateral Markers
    • Topic 2: Dams and Locks
      • Animation: Dangers of Low-Head Dams
      • Large Structure Dams
      • Locks
      • Going Through Locks
      • Traffic Signal Lights at Locks
      • What Boaters Should Do When Using Locks
    • Topic 3: Personal Watercraft (PWC)
      • Before You Go Out on Your PWC
      • Steering and Stopping a PWC
      • Video: Steering and Stopping a PWC
      • PWC Courtesy: Keep Your Distance
      • PWC Courtesy: Limit Your Noise
      • Be Aware of Blind Spots
      • Environmental Considerations for PWCs
      • PWC Safety Practices
      • More PWC Safety Tips
      • Inspecting Your PWC
      • Reboarding a Capsized PWC
      • Rolling a PWC to an Upright Position
    • Topic 4: Engine Cut-Off Switch (ECOS)
      • How an ECOS Works
      • Use of ECOS Helps Prevent Propeller Strikes
      • Video: Ignition Safety Switch (Engine Cut-Off Switch)
    • Topic 5: Avoiding Propeller Strike Injuries
      • The Most Gruesome of Boating Accidents
      • How to Prevent Propeller Strikes
      • Video: Avoiding Propeller Strikes
  • Unit 4: Wisconsin's Legal Requirements of Boating
    • Topic 1: Who May Operate
      • Who May Operate a Motorized Vessel
      • Who May Operate a Personal Watercraft
    • Topic 2: Unlawful Operation
      • Negligent or Reckless Operation
      • Improper Speed or Distance
      • Overloading or Bow Riding
      • Unsafe Condition
    • Topic 3: Alcohol and Drugs
      • Video: Alcohol Can Be Deadly
      • Minimize Risk by Avoiding Alcohol
      • Understand Alcohol Impairment
      • Operating Under the Influence
      • Blood Alcohol Concentration
    • Topic 4: Staying Clear of Other Boats
      • Obstructing Navigation
      • Homeland Security Restrictions
      • Video: Homeland Security
    • Topic 5: Personal Flotation Devices (Life Jackets)
      • Overview of PFD Law
      • Video: Wearing Life Jackets
      • Specific PFD Requirements
      • PFD Label
      • Type I PFDs: Wearable Offshore Life Jackets
      • Type II PFDs: Wearable Near-Shore Vests
      • Type III PFDs: Wearable Flotation Aids
      • Type IV PFDs: Throwable Devices (Not Wearable)
      • Type V PFDs: Special-Use Devices
    • Topic 6: Navigation Lights
      • Overview of Navigation Lights Law
      • Required Lights: Power-Driven Vessels Less Than 65.6 Feet When Underway
      • Required Lights: Unpowered Vessels Less Than 65.6 Feet When Underway
      • Required Lights: Unpowered Vessels Less Than 23 Feet When Underway
      • Required Lights: All Vessels When Not Underway
    • Topic 7: Personal Watercraft (PWC)
      • Requirements Specific to PWC
      • Proper Speed on a PWC
      • Lawful Operation of a PWC
    • Topic 8: Skiing and Tubing
      • Towing a Person With a Vessel Legally
      • Before Towing a Skier
      • When Starting to Tow a Skier
      • While Towing a Skier
      • What a Skier Should Do
      • Hand Signals for Skiers
      • Video: Water-Skiing and Wakeboarding
    • Topic 9: Boating Accidents and Casualties
      • What You Must Do if Involved in an Accident
      • Immediate Report of the Accident
      • Video: Rendering Aid and Boating Accidents
    • Topic 10: Enforcement and Penalties
      • Who Enforces Boating Laws?
  • Unit 5: Boating Emergencies
    • Topic 1: Capsizing, Swamping, or Falling Overboard
      • Ending Up in the Water Unexpectedly
      • Preventing Capsizing, Swamping, or Falling Overboard
      • Video: Capsizing, Swamping, or Falling Overboard
      • If You Capsize, Swamp, or Fall Overboard
      • If Your Boat Sinks or Floats Away
      • If a Passenger Falls Overboard
      • Preventing Falls Overboard From Small Boats
    • Topic 2: Avoiding Collisions
      • Preventing a Collision
    • Topic 3: Dealing With Fire Emergencies
      • Preventing a Fire
      • If a Fire Erupts on Your Boat
      • How to Use a Fire Extinguisher
      • Video: Fire Emergencies
    • Topic 4: Running Aground
      • Preventing Running Aground
      • If Your Boat Runs Aground
    • Topic 5: Summoning Help
      • What You Need on Board to Summon Help
      • Using a VHF Marine Radio
      • Issuing a MAYDAY Call
      • VHF Marine Radio Channels
View Course Outline

These navigation aids mark the edges of safe water areas; for example, directing travel within a channel. The markers use a combination of colors and numbers, which may appear on either buoys or permanently placed markers.

The colors and numbers have the same meaning regardless of the kind of buoy or marker on which they appear.

Red Colors, Red Lights, and Even Numbers: These mark the edge of the channel on your starboard (right) side as you enter from the open sea or head upstream. Numbers usually will increase consecutively as you return from the open sea or head upstream.

Lighted buoy—red

Green Colors, Green Lights, and Odd Numbers: These mark the edge of the channel on your port (left) side as you enter from the open sea or head upstream. Numbers usually will increase consecutively as you return from the open sea or head upstream.

Lighted buoy—green

Red and Green Colors and/or Lights: These are placed at the junction of two channels to indicate the preferred (primary) channel when a channel splits. If green is on top, the preferred channel is to the right. If red is on top, the preferred channel is to the left. These also are sometimes referred to as “junction buoys.”

Lighted buoy—red and green
Lighted buoy—green and red
upstream In the direction that is against the current
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Tag » What Do Lateral Markers Indicate