As divers, we are expected to share the water with boaters and this sometimes leads to conflict. The purpose of a dive flag is, basically, to warn boats to avoid the area where divers are underwater. Seems like a simple premise, but ignorance, confusion, and/or recklessness has resulted in many accidents and near-misses. The traditional diver-down flag was developed by divers in 1957. By 1997, nearly every state in the USA had laws requiring the use of a dive flag. Most states require the use of the traditional diver-down flag, some require only the alpha flag, and a few require both. Although federal statutes call for use of the alpha flag, some federal agencies (such as the National Park Service) insist on the traditional flag. Obviously, considerable confusion exists concerning the distinction between the two flags.



Perhaps the biggest difference between the two is that the traditional red & white diver-down flag is intended to protect divers themselves, while the blue & white alpha flag is intended to protect vessels from collision. The alpha flag is internationally understood to mean: "I have a diver down; This boat is restricted in its ability to maneuver, so keep clear and keep to a slow speed." Generally, only vessels to which the divers are physically connected by communication lines, air hoses, or the like in international water are required to display the alpha flag, but common sense suggests displaying both flags can't hurt.

Ultimately, individual state laws regulate the waters within its territory, unless federal law supercedes state law. I don't know when that happens, so maybe if would be safest to contact the Coast Guard before you go diving. Since Florida statutes regarding use of dive flags changed on October 1st, 2001, we will repeat the current requirements:

Divers-down flags must be either square or rectangular, red with a white diagonal stripe and have a stiffener to keep it unfurled and visible.

Flags must be displayed at all times when divers or snorkelers are in the water, including beach entry dive. The flag must be LOWERED when there are no divers in the water.

Flags that are towed on buoys or floats must be at least 12” x 12” in size.

On boats, flags are required to be at least 20” x 24” and must be displayed from the highest point of the boat that will present an unobstructed view from all directions.

The divers-down flag cannot be displayed in an area that would obstruct boat traffic or creates a hazard to navigation on any river, inlet, or channel, except in case of emergency.

Under state law, boaters must make reasonable efforts to stay 300 feet away from divers-down flags in open water and 100 feet away in rivers, inlets, and navigation channels. Boaters approaching flags closer than these distances must slow their boat to idle speed, or the minimum speed necessary to maintain forward motion and maneuverability.

Divers and snorkelers must make reasonable efforts to stay within the 300 feet limit of their flag in open water, and within 100 feet in rivers, inlets, and channels.

"Buzzing" a dive flag has been added to the description of Florida State Statute 327.331(6), Reckless Operation of a Vessel, which is a 1st degree misdemeanor and punishable by up to a $1,000 fine and/or up to 6 months in jail. Two convictions within 12 months of any dive flag violation will trigger the boater education course requirement.

Divers-down flag violations (other than buzzing a dive flag) are now civil violations and subject to a $50 civil penalty.

Report any violation of these rules to Florida Fish & Wildlife Conservation Commission immediately! If you are in Brevard or Indian River Counties, call 1-800- 342-9620 and 1-800- 432-2046 anywhere south of Indian River County.

References:
FFWCC Diver-Down Flag Laws
US Army Corps of Engineers Water Safety

Title XXIV VESSELS
Chapter 327 VESSEL SAFETY
327.331 Divers; definitions; divers-down flag required; obstruction to navigation of certain waters; pen