Red Flag With Diagonal White Stripe – What Does It Mean?

You may imagine the only safety matter you can encounter when out on the water is man overboard. However, there is much more to learn for good boating manners and education. You can frequently see a red flag with a white diagonal stripe flapping in the wind for no apparent reason. So, what does a red flag with diagonal white stripe mean while boating?

Quickly, it means you are near scuba divers when you see this red flag with white diagonal stripe while boating. In essence, it means stay clear before you cause any harm. When using small boats and even kayaks, you need to know such things as this, as you may need them to direct boat traffic away from you, besides watching out for others on the water or under the surface.

In our guide, you can learn more about this flag and how you can do your bit to keep water safe for everyone. By the end, you’ll know a little more about boating safety and how it can benefit everyone who likes boating on the water surface. (Learn What Safety Precaution Should You Take When Hunting From A Boat)

red flag

What Does Buoy Or Flag With White Diagonal Stripe Mean?

If you’re new to boating of any kind, you may frequently ask what the meaning of the white diagonal stripe on the red flag is.

The Diagonal Striped Flag was created in 1956 by US Divers Denzel James Dockery and Ted Nixon and immediately gained notoriety throughout the country.

A flag in the water is used to signal diver down under the surface (diver down flag).

You’ll see this scuba flag comes in two types.

In both cases, other vessels need to keep a safe distance while safe driving at a slow speed.

  1. Diver-down flag: red flags with white diagonal stripe
  2. Alpha flag: blue-and-white flag

diver tips

Dive flag tips:

  • A dive flag must be flown on a boat or vessel to display the diving site for anyone skin diving or scuba diving in federally controlled waters.
  • It is advised for boating safety that vessels not involved in diving operations stay a distance of at least 100 feet from a diver-down flag that has been displayed.
  • Snorkelers and scuba divers shouldn’t set up flags where it will obstruct other vessels’ access to the waterway or where their diving operation is already taking place.
  • Divers themselves should abide by all water safety regulations and navigation rules. (Read Is A Kayak Considered A Boat)

Flag Guidelines:

  • In North America, a white stripe runs from the upper left corner to the lower right corner of a rectangular red flag.
  • This diver down flag alerts nearby kayakers, divers, or boat drivers to potential scuba divers in the water and any nearby scuba diving activities.
  • This flag should always be flown from a boat, kayak, or floating buoy so that it may be seen by other divers, kayakers, and boat drivers.
  • Reflective material was used in the construction of the white diagonal stripe to make it more visible at night.
  • Boats and their owners know where to go and where not to go with their boats because the diving limit is roughly 300 feet from the flag.
  • To prevent any accident, boaters should first search for divers in the water, even if they aren’t flying flags with a diagonal stripe.
  • Make sure you have the proper tools on your boat for emergencies, such as life jackets and oxygen tanks.
  • To prevent propeller mishaps, shut off the engine close to the diver.
  • As any glare, big waves, or severe weather may obscure divers, look for diver down flags in the water.
  • Exercise caution when water skiing in a particular area, such as open waters. You might approach too quickly to see locations where divers are present or other kayakers and boats where fishermen are diving or fishing.
  • Specific safety equipment must be kept on board or carried by the boat’s owner or operator (USCG).

red flag on a vessel

Why Is The Red Flag With The Diagonal Stripe Displayed On A Vessel?

You must know what it entails and how important it is for everyone on the water’s safety as a boat operator or vessel owner. Here are a few pointers:

  • Keep your boat at least 300 feet (91 meters) away from the flat and any diving operations to prevent injuries.
  • You may determine where people commonly go to dive if you are driving the boat and are familiar with the area. Take it easy in some places because it’s conceivable that you won’t always see the flag, which would be against the law. People err and can break the law.
  • Try to communicate if someone approaches your boat too closely. Tell them to keep their distance and let them know you’re coming.
  • Before starting your boat, ensure no one is underneath or close to the propeller.
  • Always verify that your boat has the proper oxygen tanks, first aid kit, and other vital safety gear.
  • A scuba group may substitute SMB or DSMB (Surface Marker Buoy) buoys for the traditional mariner’s red flag in addition to the Red Alpha Flag.

When to stay away from anchoring?

  • Avoid anchoring in locations with strong currents, especially if the bottom is unlikely to protect you from dragging anchor, as with sandy or rocky bottoms.
  • Stay away from anchoring close to submerged items like underwater cables or sunken ships.

When You See a Flag With a White Diagonal Stripe?

  • This flag is frequently flown so other divers and kayak anglers can see it while paddling by displaying it on floating cargoes, a kayak, or a ship. The red flag with white diagonal stripe of the flag is reflective, making it simple to see at night.
  • While kayaking, you may encounter a red flag with a white diagonal stripe and inquire, “What does this flag mean?” The diver down flag alerts anyone fishing on kayaks and other boaters that a diver is in the water.
  • Despite not being an official flag of any nation, the red flag with a white diagonal stripe is currently state law in several states. Even though it is flown on vessels a float to indicate the diver’s general location, the “A” flag should be used on the boat.
  • Divers-down flags must be at least 20 inches by 24 inches in size and supported by a stiffener to stay unfolded. To be carried on floats, a dive flag with a diagonal stipe must be at least 12 inches by 12 inches in size.
  • Finally, diver-down flags must be displayed above the vessel’s highest point of the vessel with no objects blocking the flag’s vision. (Learn How Much Is A Pontoon Boat)
  • A diving flag may not be displayed when divers are out of the water.
  • Never go into the water when a boat’s motor runs because you risk getting hurt. Before getting in, let the engine come to a complete stop.
  • When fishing in rivers, inlets, and navigation channels, vessel operators must maintain a distance of at least 100 feet from flags and at least 300 feet from divers-down flags in open waters.
  • Floats must slow to idle speed within 300 feet of diver-down flags in open water and within 100 feet of them in rivers, inlets, and navigation channels.
  • Make emergency plans and stay safe in case of injury.
  • Avoid drinking before kayaking or scuba diving in Florida if your blood alcohol level is over 0.0 and your respiratory alcohol level is over.02. In 50% of all boating accidents, alcohol is a significant factor.
  • You should constantly be on the lookout for such flags wherever you are on the water, and other boaters should take care if you raise a red flag with a white diagonal.

The Meanings Of Boating Flags

A flag can mean a lot in the world of sailing, and flags come in a wide variety and with a specific meaning when you display them.

International Maritime Signal Flag

The international maritime signal flag transmits marine warnings and requests for help between ships and land.

The flag has two fields: a black field at the bottom for standby and a white field for warning or information.

A flag must be registered with the IMO to be an official marine signal flag (IMO).

Distress Flag

Any distressed vessel should fly a distress flag. White flags show warnings or pleas for help, whereas other colors show other emergencies.

Ensign Flag

The ensign flag has the country’s name or flag in the bottom right corner and a union jack in the top left. The ensign flag is usually the flag of the navy the ship belongs to; however, it can also be the UN flag.

Romeo Flag

Red flag with a yellow cross is the Romeo flag. A ship will display the Romeo flag when it has received your communication and can help.

Alpha Flag

Blue Alpha flags work like diving flags. Therefore, these watercraft must be displayed on ships when diving operations make navigation difficult.

Alpha flags show the diver is in a no-approach zone.

Even when the water is barely half-submerged, the flag should be flown consistently while diving to prevent collisions with other boats or underwater objects.

Echo Flag

The Echo Flag is a signal used on the water to reverse course to starboard or right. The flag is flown when the captain decides to change course for safety.

The flag flies two feet from the mizzenmast. The flag can be flown when a ship must avoid another, though it usually indicates a course change.

It’s used when the skipper can’t see the shoreline, such as in dense fog.

Always know what the flags on boats and other adjacent objects imply; they may seek help or transmit safety advice.

Red Flag With Diagonal White Stripe - What Does It Mean (1)

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