Skip to main content

Course Outline

Persons scuba diving, skin diving, or snorkeling must display a diver-down flag to mark their diving area. Vessels not engaged in diving operations must stay at least 50 feet away from a displayed diver-down flag.

Scuba divers and snorkelers should not place a flag in an area already occupied by other boaters or where their diving operation will impede the normal flow of waterway traffic. Divers also should follow all of the water safety rules themselves.

Two types of flags are used to indicate diving activity.

Diver-down flag: red flag with white diagonal stripe

Divers Flag: A rectangular red flag with a white diagonal stripe can be attached to a vessel, float, or buoy.

Alpha flag: blue-and-white flag

Alfa Flag: A blue-and-white International Code Flag A (or Alfa flag), at least 3.3 feet (one meter) high and visible from all directions, must be displayed on vessels on federally controlled waters. This flag indicates that the vessel is involved in a diving activity.

  • Unit 4 of 6
  • Topic 12 of 19
  • Page 1 of 5