Red flag with white stripe boating

Imagine yourself cruising along in your powerboat, enjoying a beautiful day on the water. Then, suddenly you spot a red flag with a white diagonal stripe. Do you know what to do?

If you spot a red flag with a white diagonal stripe while boating, you are approaching a group of scuba divers. Slow your boat down and leave 300 feet of distance between your boat and the flag.

When it comes to keeping the water safe for everyone, awareness of others is vital. This means that you’ll need to recognize and understand the significance of a variety of signs and flags used to direct boat traffic.

After all, safe driving and avoiding underwater hazards are integral parts of boating safety.

In this article, we’ll explain what that red flag means, and what you should do if you see it. Plus, we’ll make some pro recommendations for how to handle in-water encounters with one specific type of watersports enthusiast.

Want to learn more? Keep reading for all the essential information you’ll need to keep yourself and others out of harm’s way.

What Does That Red Flag Mean?

This flag was created way back in 1956, by Navy veteran Denzel James Dockery. And, it was later made popular by Ted Nixon, of US Divers. Known as the diver down flag, it’s an important piece of equipment that every scuba group should carry and display.

Today, divers in the US, Canada, and some European countries are required by law to display it while they are submerged. But, the chances are good that the diving group isn’t directly below their flag.

In open water, scuba divers should stay within 300 feet (90 meters) of their dive flag or stationary buoy. In rivers, inlets, and channels, a shorter distance of 100 feet (30 meters) is suggested. And, dive groups should plan to surface within 150 feet (45 meters) of their dive flag.

To make sure it’s easy to see from a distance, the diver down flag should be at least 20 inches by 24 inches and flown at the vessel’s highest point. If displayed from a surface marker buoy, the flag should mounted in an upright position, and be at least 12 inches by 12 inches.

In some parts of the world, divers may also fly the blue and white alpha flag. This is an internationally recognized symbol, used when the mobility of a vessel is restricted. It indicates that other vessels should yield the right of way, and is often flown alongside the diver down flag while there are divers in the water.

Boating Safety Around Scuba Divers

As a responsible boat captain or driver, you should never assume the position of divers underwater. And, when in doubt, keep your vessel at least 300 feet from their flag.

Keep in mind that not every dive group will display the diver down flag, even though it’s required by law. Even if you don’t see a flag or buoy, you should always be on the lookout for people in the water. After all, operator attentiveness is the most effective way to prevent accidents.

It’s also important to remember that divers on the surface won’t always be highly visible.

If you’re in a small, open vessel like a jon boat, glare from the sun, and rough weather conditions like high waves and swell, might make it hard to see the waterline. Larger pontoon boats are often loaded with guests moving around. This might block the view while you’re driving, and is one of the reasons passengers should stay seated any time your boat is in motion.

If you are aware of divers submerged closeby, be sure to establish clear communication with their vessel. You’ll want to keep these underwater explorers clear of your propeller at all times, even when it is not in moving. Coming in accidental contact with an immobile propeller can still cause serious injury.

Before starting your boat, make sure no divers are near or under your propeller. This can be accomplished by communicating with their captain or driver and looking for bubbles coming from below.

No matter how cautious you are, accidents can happen. Be sure that your boat has all the equipment necessary to respond to an in-water emergency. This should include a first aid kit, oxygen unit, communication devices, and a crew with extensive emergency first aid training.

You should also have an emergency response plan prepared. This detailed list of procedures should include what to do in case of an injury or accident, including details for emergency evacuation.

What to Do

No matter how much fun you’re having on the water, safety should always come first! If you come across the red flag with white diagonal stripe, your best bet is to stay away.

Divers could be performing their safety stop at very shallow depths, as little as 15 feet (5 meters) of water. And, while your engine will be loud and obvious to the submerged group, they will have a hard time telling which direction you’re coming from. Avoiding the area entirely is the best course of action for keeping everybody safe.

If you accidentally come closer than intended to divers at depth, don’t panic.

First, bring your boat to a complete stop and cut the engine as quickly as possible. While this may not be good for your motor, it’s essential to keeping the divers below you safe. A moving propeller can cause severe injuries in the blink of an eye.

Once your boat is stopped, lift your prop if possible. That way, divers who surface nearby won’t run the risk of accidentally cutting themselves, or hitting their heads on this large piece of metal.

Make contact with the dive boat and try to establish where the group is submerged, so you can slowly and safely leave the area.

More Scuba Related Boating Safety Tips

When it comes to boating safety and scuba divers, there are a few other key points to keep in mind.

In some cases, rather than flying the alpha or red flag, dive groups will display a surface marker buoy. Also known as an SMB or DSMB, this type of marker is used by dive groups during specific circumstances underwater.

In some cases, dive groups might be planning to surface in a different area than where they entered the water. This is known as a drift dive. The SMB or DSMB is used in this case to make it easier for their boat to mark their location and follow them in the water.

Prudent dive groups may also use this type of buoy during their safety stop, or if they have become lost underwater. In most cases, deploying this marker is meant to make contact with their vessel, not as a warning to others in the area.

It is also important to consider the safety of divers below your boat, even if you aren’t moving. This includes dropping ladders, swim platforms, and especially anchors. These objects are often quite heavy and may cause injury if they come in contact with divers at depth.

Other hazards include fishing lines, lures, nets, and traps. Fishing equipment can easily become tangled around scuba gear, creating a high risk for accidental entanglement. This can be one of the most extreme underwater emergencies for a diver, in some cases leading to drowning.

Passengers in your boat should use caution when entering and exiting the water at all times, but especially if there are divers in the area. Accidentally jumping onto a diver’s aluminum or steel tank can easily injure swimmers. And, depending on whether the group of divers is performing recreational or technical activities, they may be carrying heavy equipment chat could harm outsiders who come in contact with it.

Lastly, it’s important to know that divers use hand signals to communicate on the surface. A diver who is making a large circle with both arms overhead is signaling that everything is ok. But, a diver who is waving both arms from side to side in a windshield-wiper motion is indicating distress, and potentially an emergency situation.

If you come in contact with a diver in distress, only enter the water as a last resort. You should first attempt an in-water rescue by using a floatation device like a safety ring or a life jacket. You can also try throwing the diver a rope or reaching out to them with a paddle.

Keeping these items on board is essential for protecting yourself and passengers. You never know when someone from your own vessel could accidentally fall in or become panicked on the surface, requiring a similar rescue technique.

Safety and Fun for Everyone

Now that you know a bit about the red flag displayed by scuba divers and what to do if you come across it, you’re ready for a safe and fun day on the water.

Keep in mind that boating safety is a vital part of watersports, whether you’re spending time above or below the waves! And, when in doubt, you should always err on the side of safety.

Want to learn more about boats? Check out our other helpful blog posts for pro tips and tricks on buying a used boat, different types of vessels, and more.

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