Prep Guide
How to Build a 72 Hour Emergency Kit
Emergency agencies recommend every household keep enough supplies to manage on its own for at least 72 hours. That's how long it can take for help to reach everyone after a storm, earthquake or major outage. A 72 hour emergency kit isn't complicated: it's water, food, light, information and first aid, gathered in one place and checked twice a year. Here's how to build one that fits your household.
This is for educational purposes only. Not professional medical, electrical, or safety advice.
Water: the first priority
Store at least 1 gallon of water per person per day — 3 gallons each for 72 hours, more in hot weather or for nursing mothers, children and people who are ill. Pets need water too. Use commercially bottled water or clean food-grade containers, and keep them in a cool, dark place. Add a way to treat more: unscented household bleach and a dropper, or a filter followed by disinfection.
You also have hidden water at home: the water heater tank and the toilet tank (not the bowl) can provide emergency water if it's treated before drinking.
Food that needs no power
Pick foods your household already eats so nothing goes to waste when you rotate:
- Ready-to-eat canned meats, beans, fruit and vegetables.
- Peanut butter, crackers, granola and protein bars.
- Dried fruit, nuts and shelf-stable milk.
- Food for infants, special diets and pets.
- A manual can opener and disposable plates and utensils.
Light, power and information
Pack a flashlight or headlamp for each person, plus spare batteries. Avoid candles where possible — they're a leading cause of fires during outages. A battery or hand-crank NOAA weather radio keeps you informed when phones and internet are down. Keep a power bank charged for each phone, and know where your circuit breaker, water shut-off and gas shut-off are.
First aid and medicines
Keep a first-aid kit with bandages, gauze, tape, antiseptic wipes, gloves, pain relievers and any personal items. Talk to your doctor or pharmacist about keeping a few extra days of prescription medicines. Add glasses, hearing-aid batteries and anything else a household member depends on. If someone uses a powered medical device or insulin, make a specific plan for it.
Documents, cash and comfort
- Copies of IDs, insurance and medical information in a waterproof bag.
- Cash in small bills.
- Warm clothing, rain gear and a blanket per person.
- Whistle, dust masks, plastic sheeting and duct tape.
- Moist towelettes, garbage bags and ties for sanitation.
- Games or books for children.
Store it and keep it current
Keep the kit in one or two easy-to-carry containers near an exit. Make a smaller version for your car and workplace. Set two reminders a year — many people use daylight saving changes — to rotate food and water, replace batteries and update documents. Once 72 hours feels covered, build toward two weeks.
Adjust the kit for your household
No two households need the same kit. Families with babies need formula, bottles, diapers and wipes for at least three days. People with diabetes need insulin plans, a glucose meter, spare batteries and fast-acting sugar. Anyone who relies on oxygen, a CPAP or a powered wheelchair needs a backup power plan and should register with their utility company if a medical-priority list exists. Older adults may need spare glasses, hearing-aid batteries and a list of their medications and doctors.
Think about the weather too. In cold climates, add sleeping bags, hand warmers and a way to keep one room warm. In hot climates, add extra water, battery-powered fans and electrolyte drinks, and plan where you'll go if your home becomes dangerously hot.
Home kit, car kit and work kit
Your main kit lives at home, but emergencies don't wait for you to get there. A car kit should hold water, snacks, a blanket, a flashlight, a first-aid kit, jumper cables, a phone charger and comfortable walking shoes. A work kit can be as simple as a small bag in your desk with water, a snack, a flashlight, a phone charger, any daily medicines and a printed copy of your family plan. If you commute by transit, include a paper map and decide in advance how you'd get home on foot.
Go deeper with Gridfall field guides
- Start From Nothing: Your First 72 Hours — What to do first when power and water stop. Free guide.
- Hidden Water in Your Home — Water heater and toilet-tank water, safely.
- No-Cook, Low-Water Meals — Food that needs no power.
- Prescription Emergency Plan — Keep medicines going in an emergency.
- Gridfall Survival — Lifetime Access ($79) — Every field guide, the offline manual and the AI advisor, one payment.
Free download
The 72-Hour Grid-Down Checklist
One printable page: water, food, power, communication, first aid, security and documents.
Frequently asked questions
What goes in a 72 hour emergency kit?
At least 3 gallons of water per person, three days of non-perishable food, a manual can opener, flashlights and batteries, a battery or crank radio, a first-aid kit, medicines, copies of documents, cash, warm clothing and sanitation supplies.
How much water do I need for 72 hours?
At least 1 gallon per person per day, so 3 gallons each. Store more for hot climates, children, nursing mothers, people who are ill, and pets.
Where should I keep my emergency kit?
In easy-to-carry containers near an exit, in a cool, dry place. Keep smaller kits in your car and at work.
Why 72 hours?
It can take about three days for emergency services to reach everyone after a major disaster. Many agencies now suggest building toward two weeks once the 72-hour basics are covered.