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Practical preparedness

Prepare for what
actually happens.

Practical guides, calculators and gear analysis for power outages, water failures, food disruptions and household emergencies. Numbers first, sources cited, nothing sold on fear.

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Four foundations. Read them in any order, but read them before spending money on equipment.

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Popular field guides

The guides that answer the questions people actually arrive with, and that show how the arithmetic on this site is done.

power

What Size Generator Do You Actually Need? Sizing It Without Overbuying

Most people buy too much generator. They add up the nameplate wattage of everything in the house, arrive at a frightening number, and buy a unit that…

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Verified 31 Jul 2026

power

Watts vs Watt-Hours: Why the Number on the Box Misleads You

A power station named for its watts is sold on its watt-hours, and the two numbers answer completely different questions about whether your backup power will work.

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Verified 18 Aug 2026

food

"Three Days of Food": Where That Number Comes From and What It Actually Means

You have heard it in every preparedness pitch: grocery stores hold only three days of food. It's usually deployed to imply that the country is three…

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Verified 31 Jul 2026

water

Filter, Purify, or Distill: What Each One Actually Removes

Water treatment marketing uses filter, purifier, and purification interchangeably. They are not the same thing, they remove different classes of…

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Verified 31 Jul 2026

power

How Long Does the Power Actually Stay Out Where You Live?

The average American household loses power for somewhere between two hours and thirty-one hours a year, depending entirely on which state it sits in.…

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Verified 29 Jul 2026

defense

What Burglary Data Actually Says About How Homes Get Entered

Most home security advice is built on a picture of a break-in that happens at night, by force, while the household sleeps.

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Verified 29 Jul 2026

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The five pillars

The same guides, organised by what they are about rather than by what has gone wrong.

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Latest from Held in Reserve

Recently published, for readers who have been here before.