The purpose of the diver down flag is to protect divers from boat traffic. The red flag with the white diagonal stripe is the USA diver down flag, the blue and white Alpha is the international flag. International maritime tradition and law has established a set of signal flags, including flags for each letter of the alphabet. The blue and white flag signals the latter A. When used independently the Alpha flag means diver down. In 1950 a dive shop owner in Michigan, developed the US flag (red with the diagonal white stripe) after finding out that most boaters didn’t respect the red flag used by the US Navy. Over the years he helped promote it, and worked to get the flag recognized by the Michigan State Legislature as a means of protecting SCUBA divers from marine traffic. By 1997 most states had set laws requiring the use of a diver down flag.

Unfortunately, there is still a large discrepancy among the states and municipalities as to the requirements for size of the flag and the distance boater must stay away. Also, dependant upon where you dive, fines can range from $100 to $500.

Some costal states in the US actually require the use of the alpha flag. For us here in Washington State, we are required to use the Alpha flag on state waters (when boat diving), but the city of Seattle requires the red and white flag. For both locations, when shore diving, use the red and white USA flag. There’s a bit more info about these regulations here: http://apps.leg.wa.gov/WAC/default.aspx?cite=352-60-060.

When divers are using the flag, boaters are required to stay 100 yards/300 feet away or approach at idle speed. The City of Seattle will allow you to set your flag at a fixed point as long as you don’t surface more than 50 feet away from it. You may also tow your flag to be certain you are never far away from it. When towing the flag, don’t secure it to you or any part of your gear and make sure that it has an easy break away system. Accidents have occured where a boat propeller has gotten wrapped around the line and pulled the diver up, and cases where jet skiers have used our flags as a slalom obstacle course! The best way to carry your flag with you is to attach it to a reel (with enough line for your deepest depth) and keep the reel in your hand. In case it gets caught you can easily let it go.

Recently, a group of my friends got a warning from the Seattle Police Department for suffusing too far away from their flag. (Note: only one dive flag per team of divers is required.) You can read all about the no diving zones and the diver down flag at the Seattle Police Department website:
http://www.seattle.gov/police/units/harbor/harbor_diving.htm

As responsible divers we must follow the rules set by the city or they may use this as a reason to take our dive sites away. We already have places in the country where there is no diving allowed after several incidents made the municipality fear liability and close the site for divers. We also have places where rules are so strict that you can get banned for life. An example: One of my friends was diving at a very popular site in Florida. After a 5 minute safety stop his buddy got out of the water but his computer signaled a few more minutes of required time. To be extra safe he stayed in the water by himself at the 15 foot stop. When he finally exited the water, a park ranger was waiting and gave him a written warning. At this particular location if you get two warnings, you’re no longer permited to dive there.

Be safe and sure. When traveling to a new dive site, please check all local SCUBA laws and double check with the local dive shop.