An emergency kit is a portable collection of basic supplies your household needs to survive on its own for at least 72 hours after a disaster.
When the power goes out for a week, a storm blocks the roads, or a wildfire forces an evacuation order, the stores close and the taps can run dry. An emergency kit is the box of supplies you grab on the way out the door — or reach for in the dark — that keeps your family fed, hydrated, and safe until help arrives or services come back. The federal guidance from Ready.gov defines it simply: a collection of basic items your household may need in the event of an emergency. Canada’s federal preparedness guidance uses the same 72-hour standard, so the rule is consistent across North America.
The whole concept rests on one number: three days. That’s the minimum window of self-sufficiency experts agree every household should plan for, and it’s the number every official checklist builds around.
Why 3 Days Is the Standard
Ready.gov bases its entire kit recommendation on this 72-hour window, and the logic is simple: roads get blocked, supply chains break down, and first responders prioritize life-threatening injuries before routine needs.
The kit is designed for two distinct scenarios. The first is sheltering in place, where you stay home but lose power, water, and heat. The second is evacuation, where you grab the kit and leave quickly. A well-built kit works for both — which is why it needs to be portable and stored in one accessible spot.
What Goes In an Emergency Kit
The official list from Ready.gov covers the basics every household needs. The table below compresses the essentials into a single reference:
| Category | Official Recommendation |
|---|---|
| Water | 1 gallon per person per day for at least 3 days |
| Food | At least a 3-day supply of non-perishable items |
| Light | Flashlight with extra batteries |
| Communication | Battery-powered or hand-crank radio that receives NOAA Weather Radio alerts |
| Health | First aid kit, prescription medications, and glasses |
| Tools | Whistle, dust mask, non-sparking wrench or pliers, manual can opener |
| Sanitation | Moist towelettes, garbage bags, plastic ties, hand sanitizer |
| Shelter | Plastic sheeting and duct tape for shelter-in-place |
| Documents | Insurance policies, ID, and bank records in a waterproof container |
| Comfort | Sleeping bag or warm blanket, complete change of clothing, sturdy shoes |
Beyond the basics, customize for your household. Infants need formula and diapers; pets need food and supplies; anyone on medication needs a backup supply. Cash and change matter because ATMs and card readers go down with the power. The National Institute on Aging’s emergency kit guidance adds another layer for older adults: a list of medications with dosages, extra hearing aid batteries, and a plan for mobility devices.
How to Build and Maintain Your Kit
Building a kit is a one-afternoon project. Gather supplies for at least 3 days and store them together in an easily accessible place — a plastic bin, a knapsack, or a suitcase with wheels all work. Canadian guidance specifically suggests a knapsack or suitcase because it needs to be carryable if you evacuate on foot.
Pick a spot everyone in the household knows. A hall closet near the front door beats a basement corner you’d have to navigate in the dark. If you have a larger family or live in a cold climate, consider a second kit for the car.
More important than building the kit is maintaining it. Check it twice a year — when the clocks change works well as a reminder. Refresh food, water, batteries, and medicines before they expire. Rotate stored water every six months. Replace outgrown clothing and update documents as policies and IDs renew. A kit you built once and forgot is a kit that fails when you need it.
One note on radios: the official guidance specifically calls for a radio that can receive NOAA Weather Radio tone alerts, not just any AM/FM unit. Those alerts are how you’ll hear about severe weather and evacuation orders when cell towers are down.
FAQs
How much water should I store per person?
Store at least 1 gallon of water per person per day for a minimum of 3 days. That covers drinking and basic sanitation. For a family of four, that’s 12 gallons minimum. In hot climates or for pregnant women and people with medical conditions, add more.
How often should I replace kit supplies?
Check your kit twice a year and replace anything before it expires — food, water, batteries, and medications all have shelf lives. Use the daylight-saving time changes as your reminder. Rotate stored water every six months and swap in fresh batteries even if the old ones seem fine.
Where should I store my emergency kit at home?
Store it in one easily accessible place that everyone in the household knows about. A front-hall closet or near an exterior door works best so you can grab it quickly during an evacuation. Avoid basements and attics — you need to reach it fast, not after a hunt.
Ready with the basics? Our tested roundup of the best emergency kits for home breaks down the top pre-built options and what each one actually includes.
References & Sources
- Ready.gov. “Build A Kit.” Official U.S. federal guidance defining the 3-day standard and the complete basic supplies list.
- Government of Canada. “Get a Kit.” Canadian federal preparedness guidance using the 72-hour standard and advising knapsack or suitcase storage.
- National Institute on Aging. “10 Emergency Kit Essentials.” Adds older-adult-specific items like medication lists and mobility device planning.