Survival at sea - How to stay afloat in water

The biggest fear of a boater is to fall overboard and emerge from the water only to see their vessel drive on towards the horizon. Thankfully, this is not a common occurrence. There are countless ways to prevent it from happening. Yet, it’s useful to know what to do in such an extreme and unlikely situation. In this article, we look at how to stay afloat in water and stay alive for as long as you can.

There will be circumstances over which you have no control, such as water temperature and sea conditions. However, you can make the most out of your situation.

A person can survive for an hour in 5°C (41°F) water, 2 hours in 10°C (50°F), 6 hours in 15°C (59°F), and over 25 hours in 20°C (68°F) and above. After a number of hours in the water, you can succumb to hypothermia - a gradual lowering of the core body temperature below the survival temperature.

In waters under 15°C (59°F), you may go into cold water shock. This means you lose control over your breathing and potentially inhale water. As your body temperature cools, you become tired, confused, and disoriented.

It’s easier to survive in calm and warm seas than in cold, rough ones. But what you do is very important, too.

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How to stay afloat in water and survive at sea

Below we have listed the best tips to stay afloat to prolong your chances of survival.

Note that you should be comfortable in the water and know how to relax your body in order to float, as this is the main thing you’ll need to do. We also recommend being able to swim.

Boat with clothes and shoes on

Every item of clothing you wear will trap in air as you fall overboard. So having shoes and other layers of clothes on will help improve your buoyancy. Of course, you should also wear a life jacket.

Check your life jacket

Before leaving the dock, you should have ensured you’re wearing your life jacket properly. However, it’s best to check that it’s still well secured to your body after the fall. You can’t risk losing it.

Look for floating objects

As soon as you fall into the water, scan the area around you to see if anything that floats fell with you. For example, an empty jug or a pool noodle. Swim towards it. If you’re wearing a life jacket, swim sideways or using back-strokes for short intervals to conserve energy.

Once you’ve reached the floating object, hold onto it and don’t let go. It’s even better if the floating object is big enough to keep you out of the water. Is there anything bright (orange, pink, or yellow) in the water? Hold onto it.

Float, don’t swim

You can prolong your life by slowing down the rate at which your body cools down. The best way to do this is to float, not swim. In calm water, float horizontally on the surface with your knees raised to your chest. If the sea conditions are rough, float vertically and focus on not inhaling water.

Moving around will disperse the air trapped in your clothing and shoes, making you less buoyant and dispersing heat, so stay as still as you can.

Make a flotation device with your clothes

If you’re not wearing a life jacket (you really should), try to make an improvised buoyancy aid out of your clothes.

The best piece of clothing for this purpose is trousers (pants). Take your trousers off and tie a knot in the ends of the legs. Zip up the fly and tie the two legs together into a square knot, trapping air as you do it.

Put the waist opening over your shoulders, raise it above your head, and swing it around to scoop in air, then slam it into the water. Close the waist underwater to trap the air. Put the legs around your neck and hold the waist closed, underwater. If they deflate, trap new air in. Keep the trouser legs wet.

If you’re not wearing trousers, try to trap air in any other piece of clothing you're wearing, such as a t-shirt. Any kind of floatation will help.

Try to calm yourself down

In dangerous situations, some people panic, some are paralysed, while others will immediately take action. No matter your reaction, try to calm yourself down, as hard as it may sound. Tell yourself you need to stay calm to stay alive. Take some deep breaths as and when you can. You need a clear mind to assess the situation and do the right thing.

Convince yourself you will survive

Your mental attitude will have an impact on how you behave. If you think you’re going to die, you won’t be as resilient and will easily give up. If, however, you can tell yourself: “I will not die today”, you will do the very best you can to stay alive. A positive attitude will help your chances of survival.

How long can you survive in the ocean?

Surviving at sea is not impossible, although it requires mental toughness and some luck. As we’ve seen above, water temperature and sea conditions will play a major role. Have you heard of these two outstanding stories of survival at sea?

In 2006, Mexican fisherman Jesus Vidana and his crew spent 270 days adrift in the Pacific Ocean. They were rescued by a Taiwanese tuna fishing boat.

In 2013, Jose Salvador Alvarenga, from El Salvador, swam ashore one of the Marshall Islands, having spent 440 days drifting across the Pacific Ocean.

The two men say they survived on raw fish, sea turtles, and rainwater. Grabbing and holding onto any useful gear that fell off their boats allowed them to stay alive for such long stretches of time. Their stories sound unrealistic, yet experts have not come up with more credible ones.

Prevention is crucial

The best way to stay safe on the water is to minimise risk. While it’s very useful to know what to do if you do end up having to survive at sea, it’s better (and easier) to stop it from happening in the first place.

Here are some ways to prevent having a boat accident and falling overboard:

if you’re a newbie, take a boating course
keep a proper lookout
don’t drink while boating
go at an appropriate speed
wear a tether, as well as a life jacket
move carefully around the vessel, especially underway
follow the COLREGs
maintain your boat to a high standard
at night, set alarms to ensure you stay awake
carry all mandatory safety equipment on board.

If you have an emergency at sea and you’ve not fallen overboard, don’t abandon the vessel unless absolutely necessary - if there’s a fire on board, or it’s about to sink. Even then, stay nearby. The fire could cease and the boat may still be visible from the sky by emergency services.

You have a much higher chance of survival and of being found if you stay onboard. There likely are communication devices, food, and water on the vessel. Stay on it or with it if you can.

Wonder how to call for help in an emergency at sea? Read this article.