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Survival Rule of 3- What To Do First

Survival Rule of 3-What to Do First

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What is the Survival Rule of 3?

What happens if you are in a plane crash, lost, trapped in the woods, or outdoors? What should you do first?  Figuring out what needs to be a priority is why you should know the Survival Rule of 3.

The Survival Rule of 3 describes how long we can survive without having our most basic, physical, and social needs met.  The Rule of three helps you to prioritize your survival needs in a given situation. The most time-sensitive need is listed first.

You can survive:

  • 3 minutes without air.
  • 3 minutes in cold water.
  • 3 hours without shelter.
  • 3 days without water.
  • 3 weeks without food.
  • 3 months without social interaction.

The Rule of 3 for Survival focuses on maintaining homeostasis.  You have to have a stable internal environment; this includes getting enough oxygen to your cells, keeping a body temperature that is not too hot or too cold, and getting enough water and nutrients.

The Survival Rule of 3 also describes our social needs.   Human beings are social creatures and can survive only a limited time without any social interaction.

Our bodies have built-in mechanisms, like shivering, to generate heat when it’s cold as well as perspiring, to stay cool when the temperature rises.

But in survival scenarios, these are not enough. We have to modify our environment to keep our internal balance.

3 minutes without air

With the current pandemic situation, many people disregard their respiratory system’s essential function to take in air to provide oxygen to their cells.  You can only survive three minutes without air.  So do anything you can to protect your respiratory system,  such as wearing a mask.

In most outdoor survival situations, lack of air may not be the immediate consideration, but getting enough oxygen in a fire or a medical emergency where the airway is blocked is essential.

Time is critical during a fire because you can pass out and die quickly from a lack of oxygen. Instead, oxygen in the air is replaced by carbon monoxide, making it deadly to breathe.

It is important to stay low to the ground during a fire. You will avoid breathing less smoke because smoke and heat rise.

3 minutes in cold water

Survival Rule of 3, 3 Minutes in Cold Water You can survive only three minutes in cold water. Being in cold water is dangerous because it can lead to death from hypothermia.  Hypothermia is abnormally low body temperature, from the core 98.6 degrees Fahrenheit, 37 degrees Celsius.

In hypothermia, your body is losing too much heat and cannot maintain its core temperature. Heat is removed first from the extremities, the feet, the hands, and directed to vital organs:  the heart, the lungs, kidneys, and the brain.

The electrical activity that happens in the brain and heart are sensitive to cold temperatures, slow these electrical impulses down, and your body eventually stops.

As hypothermia begins to set in, it becomes difficult to move and for you to think of ways to stay warm. Hypothermia can happen at temperatures as low as 40 degrees Fahrenheit, 4.4 degrees Celsius when a person is wet.

3 hours without shelter

Survival Rule of 3, 3 hours without shelter

To avoid prolonged exposure to wind, rain, extreme cold, or heat seek shelter, to keep your body functioning optimally.  After three hours without shelter, your body begins to experience the following symptoms.

The effects of extreme heat

If you expose yourself to extreme heat for a long time, it can lead to hyperthermia, and the body’s overheating. Hyperthermia symptoms can range from rapid breathing, nausea, confusion, vomiting, brain damage, to a coma, even death.

Several measures can be taken to avoid hyperthermia in a tropical or desert environment.  These include covering yourself from direct sunlight.  Cover your head, hair, neck, and legs.  Wear light, loose clothing, and avoid working outside in the sun.

The effects of extreme cold

The other extreme to avoid is cold weather with wind and or rain.  Extreme cold can lead to frostbites. Frostbite results in the skin and underlying tissue being destroyed; it affects the fingers and toes and the ears, nose, cheeks, and chin, resulting in loss of limb.

You cannot survive exposure to the cold and wind after three hours, so take precautions.  Wear layers to trap the warm air.  If you are doing physical activities, remove layers to avoid trapping moisture, and put layers back on when you have finished.  You want to avoid hypothermia.

Find shelter now

Finding shelter from extreme heat and cold is imperative.  Be inventive and use whatever debris, tree branches, sticks, rocks, and leaves in your environment to construct a small hut.

3 days without water

When you are looking for items to build a shelter, also look at water and food.  After three days without water, you will have severe dehydration. The body is over sixty percent water.  You need water so our cells can perform their functions.  Without enough water, you soon become light-headed, experience dry mouth, dry eyes, fatigue, and constipation.

An excellent way to check our level of dehydration is our urine output.  The lighter the urine color, the more hydrated we are, and the darker the urine color, the more dehydrated we are.

Depending on the environment, there are various things to look for that can direct you to water.

  • Look for sources of fast running water.
  • Pay attention to dense vegetation areas, different animal tracks going in the same direction, or birds flying low; these can indicate water nearby.
  • Water can also be collected from dew using a piece of fabric and then ringing out the water. Also, you can get water from leaves with a plastic bag around them.

3 weeks without food

Many people have gotten used to eating three times a day with snacks.  But, in a survival situation, food is not the main priority. You can go three weeks without food.

In a survival scenario, catching your food requires some skill.  The safest thing to eat is fish or find small furry animals.  If you think you can’t handle catching or eating these animals, alternative food is insects. Eating live worms under logs can also be a safe choice.  Avoid eating brightly colored insects or insects feeding on feces, trash, or dead animals; they are likely to carry disease.

Foraging for plants or mushrooms can be dangerous if you cannot distinguish which are poisonous and safe to eat.   If you can, observe plant-eating animals, herbivores and see what they are eating; these plants may be safe for human consumption.  But only if you do the universal edibility test.

Remember, you can go about twenty-one days without food; it is better to eat safe foods than poison yourself with variety.

3 months without social interaction

Survival Rule of 3, 3 Months Without Interaction

Most people do not think of social interaction or other psychological needs when considering their basic needs, but humans need to belong.   You will find it is challenging to be completely alone.

If stranded, people are not going to settle in and make a permanent home immediately.  They will look for ways to signal for help,  make plans to survive until help arrives,  or begin a journey back home to their families.


Being prepared for any disaster means you must know the Rule of 3 for Survival:  how long you can survive without air, shelter, water, or even food. 

Based on the situation you find yourself in,  the Survival Rule of 3 will prioritize what is most urgent.



Welcome to Survival Skills Now.
After seeing and experiencing some of the effects of global warming, increased floods, hurricanes, tornadoes, forest fires, and other situations, I see the importance of prepping. It is my mission to present survival skills information so that we can prepare for any survival situation.

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