Survival

Staying alive in Pollution is more than a health bar. Your blood is your health, and four things wear you down over time: hydration, energy, body temperature and, in bad air, toxicity. Let any of them run out and you start losing blood until you die.

Blood is health

You have 5000 ml of blood and die when it falls to 3000 ml. Wounds bleed it away, and so do hunger, thirst, extreme cold and heat, and severe poisoning. With no open wound your blood slowly comes back. How hits, bleeding and treatment work is on Wounds and treatment.

Hydration and energy

	Hydration	Energy
Full to empty at rest	40 min of play (2.5 days of game time)	1.3 h of play (5 days of game time)
Faster in	heat: +5% per °C above 26 °C felt	cold: +3% per °C below 10 °C felt

Sprinting drains both 2 times as fast.
Carrying too much drains both faster: +2% for every kilogram over your encumbered weight.
Being Sick drains both 1.5 times as fast.
Below 25% of either, your blood and limbs stop healing. You are Hungry or Thirsty below 25%.
At 0 you are Starving or Dehydrated and lose 7 ml of blood a second for each: from full blood that is about 4 min 46 s to death.

Eat and drink to fill them up: every food and drink is listed in Food and drink. The Survivor perk makes both drain slower.

Stamina

Stamina is your sprint pool. It drains while you sprint and refills when you stop.

Energy sets its size: at empty energy the pool is 25% of full and refills at 50% speed, growing evenly to full at 75% energy.
Below 25% hydration the pool shrinks to 75%.
A melee swing costs 4% of a full pool, and a swing at a tree or a rock 5%.
Weight over your encumbered limit drains it faster: +5% per kilogram, at most 3 times as fast.

Carrying weight

You can carry 30 kg before you are overloaded, and become encumbered at 60% of that (18 kg). Bags such as the Backpack and the Small Pack, and the Strong back perk, raise the limit. Over the encumbered weight:

you walk 1.5% slower per kilogram, down to at least 60% of your speed;
hydration, energy and stamina drain faster (see above).

Nothing ever stops you from picking things up: the limit is soft.

Body temperature

Your body sits at 37 °C as long as the temperature you feel stays between 10 °C and 26 °C. Outside that band it drifts down (or up) by 0.2 °C for every degree you feel below (or above) it, taking a few minutes to get there.

What you feel starts from the air where you stand:

the climate of the place, from -15 °C in the coldest lands to 40 °C in the hottest, shifted by the season;
minus up to 8 °C at night (coldest around 03:00);
minus 3 °C on snow and ice, and 6 °C underground;
indoors and at home, a shelter pulls it 70% of the way to 18 °C;
a fire warms you; see base building;
being wet chills you by up to 8 °C;
your clothes add their insulation, but only up to 26 °C: they help against cold and never make heat worse. Compare them in Clothing, armour and bags.

State	Body temperature	Felt temperature (about)	What it does
Cold	below 35.5 °C	below 2.5 °C	blood and limbs heal at 50% speed; energy drains faster
Freezing	below 34 °C	below -5 °C	as Cold; below 33 °C body (about -10 °C felt) you lose 7 ml of blood a second
Hot	above 38 °C	above 31 °C	hydration drains faster
Overheated	above 39.5 °C	above 38.5 °C	as Hot; above 40 °C body (about 41 °C felt) you lose 7 ml of blood a second

Below 5 °C felt, bare hands get Cold hands: wear Leather Gloves to keep them warm.

Getting wet

Wading in water or marsh soaks you in 20 s; you are Wet from 50% wetness, and dry again 5 min after you leave the water. Rain soaks you too. Wet clothes make you feel colder.