The Rule Of Three
What Is The Rule Of Three?
In a survival situation, the rule of three states that you can survive:
3 hours without shelter
3 days without water
3 weeks without food
Sounds catchy right, but what does it actually mean? Let’s get into it.
At the most basic level it is your survival checklist, to make sure you work on your survival priorities in roughly the right order.
Being short and catchy makes it easy to remember. Ideal for a stressful situation where you need to focus on the next best thing to help you survive.
Sourcing food before water is the classic mistake. You have weeks to find food, but only days to find water.
Focus on water for the first 48 hours
Three Hours Without Shelter
Exposure
Exposure is usually what kills people stuck out in the woods, lost up a mountain or adrift at sea. Long before dehydration or starvation.
The human body has a few tricks to help maintain a core body temperature:
Seeking shelter from the elements
Shivering to burn calories to generate heat
Sweating to reduce heat via evaporation
These tricks are known as Behavioural Thermoregulation but they are limited and will run out.
They kick in when you are in an extreme cold / hot / wet / sunny environment, but don’t have access to the shelter you need to protect yourself.
Shelter can be offered by clothing, trees, buildings, walls, tents or even a hill.
What Does Exposure Look Like?
Scenario 1
You went out into nature on a hot sunny day in shorts and a t-shirt. The wind picks up, it starts pouring it down and the temperature plummets.
Your risk of getting hypothermia is suddenly quite real.
You need appropriate clothing or a shelter to block the wind and keep the rain off.
Scenario 2
You find yourself stuck out in the open on a hot day and the UV index keeps climbing.
The risk of getting sunburn or sunstroke increases.
You need shade from appropriate clothing or a roof over you.
Strategies For Dealing With Exposure
In urban / city settings you can often find a pre-made shelter to use e.g. a bus stop or doorway.
Out in nature a tree might offer some protection from the rain for a bit or a stone wall protection from the wind.
Many of the risks mentioned above can be also be countered with the correct clothing. This can be what you are wearing or what you have packed in your bag.
Read the guide to shelter in survival situations.
Dress for the expected weather and pack clothing to increase shelter if needed
Three Days Without Water
Ideally you wouldn’t want to go a whole day or even, at a push, two without water.
Waiting until day three is risky because dehydration can start to degrade your physical and mental performance.
Take Into Account Climate And Activity Level
If it’s hot or humid you will use more water to keep cool by sweating.
If your activity level increases, while climbing a mountain or walking a long distance, you will need more water.
Climbing a mountain on a hot and humid day without water is a very bad idea.
Water For Survival
For humans and animals alike, water is and will always being priority number one.
Take some with you, know where to find more and have the ability to make it safe to drink.
The UK Government recommends drinking at least 1 litre per day, or more if doing strenuous activity.
On the move remember that water is very heavy and there is a limit to how much you can carry..
Finding Water In Nature
Drinking water from lakes, rivers, streams or collected rain water is not recommended.
It should be filtered to remove larger particles and purified to kill any parasites / bacteria / viruses before consuming it.
Water from a stream may look clear but the living organisms which can make you very sick are too small to see with the naked eye, there may be chemical pollutants dissolved in the water and you simply don’t know what animals have died / pooped into it upstream.
Read the guide to finding water, water collection, filtering and purification.
Three Weeks Without Food
Three weeks sounds like a long time to go without food, however most survival situations don’t last that long.
If you are free to move about it’s possible to walk a pretty decent distance each day to look for food and if you learn anything about foraging you will soon realise food is never far away.
Ketosis
The human body is smart enough to deal with short periods of starvation.
It stores calories as fat when they are available and will switch over to using these fat stores for energy if it needs to.
This metabolic state is known as Ketosis and simply means burning fat for energy instead of glucose from digested food.
Leaner bodies have less fat reserves to use during Ketosis, so have less time in a survival situation.
Survival Food
We suggest keeping a bag of KP Nuts and an emergency ration bar in your bag but some people also like to carry chocolate bars and high energy drink mix sachets.
Read the guide to prepping and survival foods.
Pack calorie dense food in your EDC setup
Where Did The Rule Of Three Come From?
Air
The modern rule of three usually starts with “3 minutes without air”.
While that is about right, it isn’t worth remembering it.
If lack of air becomes a problem it isn’t something you can magic up in most scenarios!
Help
Some people like to add “three months without (human) help”.
This refers to the fact that longer term survival almost always requires humans to band together for the greater good.
With a self supporting group individuals can start to specialise in different elements of survival, creating efficiencies.
Some might handle water collection and purification while others handle food / shelter / security / entertainment etc.
Why Rules Of Three Work
The original rule of three most likely started as three rules before picking up air more recently.
Aristotle, an ancient Greek philosopher (clever dude), worked out that humans find it easiest to remember three things about any given concept.
You’ll notice this happening everywhere in life, from TV adverts to rules of thumb to children’s books.
Three elements of a certain concept is easy for the human mind to process and remember. The beginning, middle and end.