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Diving Flags, What Two Types of Diver Flags Are and What Do They Indicate?

diving-flags - banderas de buceo - main

I started in the scuba world for love. My husband, a dive instructor, showed me the underwater world. So, I could not avoid falling in love with it. Diving, I mean.

I remember that, on one of my first visits to the school, I was amazed by the number of diving flags. They were everywhere.

Well, the truth is that I did not yet know that they were diving flags nor that they had a precise meaning. I only saw red and white-blue flags, and I thought they were having a party in the sea, and nobody had invited me. I was wrong; they did.

Today, after 20 years as a diver, I write to reveal the secrets of diving flags and their purpose. For this, I rely on the Divers Alert Network (DAN). This is because diver flags are to improve the sport’s safety, and if there is an institution that watches over precisely this, that is DAN.

diving-flags - banderas de buceo

1. What Color Is a Diving Flag?

Let me tell you the story of scuba diving flags.

Ships are crossing the seven seas, each leaving from multiple ports, coming from separate places, and going to different destinations.

Their crews usually come from numerous corners of the planet.

They do not share the same language; neither know what language the other speaks.

However, they take out their little flags and send each other messages. On a boat, everybody understands the meaning of nautical flags from a distance and without a word.

Nautical flags use the international code of signals (CIS) that allows visual, simple, and fast communication on the high seas, also between ships and ports.

Each flag has a different shape and color. It corresponds to a letter of the Greek alphabet and the numbers from 0 to 9. If flown alone, some flags have a specific meaning.

The white and blue flag corresponds to the letter “Alpha” and is one of our diving flags. But it was not the first.


  1.1. Divers Down Flag: Red Flag with White Diagonal Stripe

In the 1950s, and due to the growing popularity of scuba diving, James Dockery, a U.S. Navy diver, decided to design his diving flag.

He was inspired by the nautical flag code, specifically the “Bravo” flag.

Bravo flag alone means “loading and unloading dangerous goods” (usually explosives). So, Dockery thought that a flag similar to the bravo flag would deter ships from approaching the divers.

He placed a diagonal white stripe on a red square, and its use was spread by the diving magazine Skin Diver, especially among the American public. As the most widespread certifying agencies are American, more and more divers knew this flag.


   1.2. Alpha Flag: White and Blue Scuba Flags

Meanwhile, the alpha flag was used by divers freely in Europe until 1961.

That year, the Inter-Governmental Maritime Consultative Organization (IMCO), which did not see the need to include a new flag in the nautical code, chose the alpha flag (white and blue) to indicate diving operations.

It is therefore internationally recognized and in use. Note that vessel captains do not necessarily have to be divers, but they have to know what the nautical code flags mean.

2. What Do the Scuba Diving Flags Indicate?

So, Yes. The two dive flags mean the same thing. Basically, “There is a diver down. Keep well clear and slow speed.”

The goal is to avoid collisions and accidents between boats and, on top, to keep divers safe.

However, as the diver down flag is well known to divers, it is also used on land. It signals dive centers and dive stores as a wake-up call identifying their services.


3. How Should a Ship’s Crew Proceed When They See a Scuba Diving Flag?

According to DAN, the boat’s crew must keep the ship at a safe distance of at least 300ft (90m) from the diver down flag in the open water sea.

When the diver’s flag is in rivers, inlets, or navigation channels, the distance with the divers’ flag should be at least 100ft (30m).


4. How To Use Diver Down Flags According To DAN?

In addition to staying beyond 300ft (90m) from the flag in open water and beyond 100ft (30m) in channels, divers must be mindful of the size of their flags.

According to DAN, when the diving flag is flown from a boat, it must be at the vessel’s highest point and measure at least 50×60 cm / 20×24 in.

If the flag is on a buoy, (pon link al artículo de las boyas que no se ha subido aún),  the size of the diving flag must be 30x30cm / 12×12 in.

To sum up, the alpha flag is internationally recognized, and any skipper in the world knows its meaning. The diver down flag is the most recognized among divers.

One last piece of advice. If you hesitate about which dive flag to use, use both.

What is your favorite diving flag, the alpha flag or the diver down flag? Share your comment on Facebook.