It's the Law: On the Water With Your Vessel

Diver Down Flags

Vessel operators must stay at least 200 feet away from a “diver down” flag. If a vessel must approach this warning flag, it must do so at a “no wake speed.”

The commonly used diver down warning flags are:

Divers Flag A rectangular red flag with a white diagonal stripe attached to a vessel, float, or buoy.	Alfa Flag A blue and white International Code Flag A (Alfa flag), flown from a vessel.