Survival and the Rule of Threes (What it all Means)

 Survival and the Rule of Threes (What it all Means)

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The survival rule of threes is a set of ‘rules’ that once understood, can better help you prioritize your needs during a survival situation. These rules are not guaranteed however, it would be very dangerous to allow your body to have to get even close to these rules. The survival rule of threes are:

  • 3 minutes without air
  • 3 hours without shelter
  • 3 days without water
  • 3 weeks without food

Now, as you can see, you could last longer than 3 hours without shelter, however, if you fall in to a cold lake for instance, you might not last much longer than that time. Or in extreme heat, without the ability to get away from the elements, you might not last 3 hours. This list is about getting your priorities in order as each person will last more or less than the next person but their priorities will always be the same.

3 Minutes Without Air

Three minutes without air

Now I am not about to ask you to see how long you can hold your breath for but 3 minutes is a good guideline. Having to go longer than 3 minutes is dangerous and could lead to brain damage.

The interesting fact is that we can actually hold our breath for longer periods of time when we are underwater than we can in the air. This is due to a mysterious function that is known as the mammalian diving response. This allows us to easily subdue the reflex that forces us to breathe – and drown. If oxygen is limited, you must try to get yourself into a situation where you breathe.

3 Hours Without Shelter

Three hours without shelter

Your next priority would be to find some form of a shelter so that you are not exposed to the elements. You actually have many options of shelter from a tarp or tent, to man-made structures, to natural shelter, or building your own from the materials that are around you at the time.

For those that die in the wilderness, exposure is the leading cause. If your body is out of its normal range for too long (gets too hot or cold) it will start to shut down. With shelter you also have to think about the ground and what you will be laying on. You could have a great shelter that stops all rain but if you’re laying on a cold floor it could still be just as deadly as being outside. Fire also falls into this category so having the knowledge to create a fire is also essential.

3 Days Without Water

Survival Basics water

Your third priority is water. Sure, you could last three days without water but you are putting your body into a very dangerous situation. Dehydration that causes a loss of more than 10 per cent of your body weight is a medical emergency and if it’s not reversed it can lead to death.

At least 60% of the human body is made up of water and every living cell in the body needs it or they can’t function. Our body is constantly losing water throughout the day even just by exhaling. If that water is not replaced, the total volume of body fluid can fall quickly and, most dangerously, blood volume may drop. When you have too little blood circulating in your body, blood pressure falls to levels that can be fatal. Body temperatures also rise when we stop sweating.

Conditions play a big part in how long somebody can go without water and in excessive heat for example, you wouldn’t last very long at all.

It is wise to always assume that water sources around you may be contaminated so you need to have the tools or the understanding to purify the water before drinking.

3 Weeks Without Food

Emergency Food Items With a Long Shelf Life

While food may be our last priority, it is still incredibly important. It is hard to put a number on how long the human body could go without food as Terence MacSwiney the Irish political prisoner in 1920 lasted 74 days on a hunger strike before his death.

Like water however, your body needs food to keep you alive. If it isn’t getting food it starts to use up glycogen in the liver and muscles to produce a sugar called glucose, followed by some amino acids. Following this, your body will start processing fat stores and then its own protein.

Just because food is the last in the order of your priorities, it doesn’t mean that it is any less important than the rest. Going without food will eventually lead to death the same as going without air.

I hope you have enjoyed this guide and please share any tips that you have in the comments below. Also if you enjoyed it, please help us out by sharing this post using the buttons at the top. Thanks!


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