The 72-Hour Emergency Kit, Rebuilt Around What People Actually Use

The Short Answer: Six Functions, and the Minimum That Covers Each

Build to functions. Items are interchangeable; functions are not.

• Water — 1 gallon (3.8 L) per person per day, 3 days minimum. Roughly half of that is drinking, half is hygiene and cooking. Ready.gov sets one gallon per person per day and a three-day supply for evacuation, with two weeks stored at home.
• Food — 3 days per person of food that needs no cooking, no refrigeration and no water to prepare. Plus a manual can opener, which is the single most-forgotten item on the list.
• Warmth — one complete dry insulation layer per person, plus a hat, gloves and two pairs of wool or synthetic socks. A house without power drifts toward outdoor temperature. You are sleeping in it.
• Light — one hands-free light per person, not one shared lantern, plus one spare set of cells in the same chemistry across every device.
• Information — a battery or hand-crank radio that receives NOAA Weather Radio, and a way to charge a phone. Alerts and evacuation orders come from the National Weather Service and local authorities, and they reach you whether or not the cell network is up.
• Medical — your prescriptions, plus a first aid kit you have actually opened. Medications are the item nobody can substitute for you.

Everything after those six is a comfort or a convenience. Comforts are worth carrying; they are just not what makes a kit adequate. Ready.gov's own basic list adds a whistle, a dust mask, moist towelettes, garbage bags and plastic ties, a wrench or pliers for utility shutoffs, local paper maps, and a phone with a charger and backup battery — all reasonable, all secondary to the six.

One honest framing note: 72 hours is a floor chosen because three days is roughly how long you may be on your own before organised help reaches an ordinary household. It is not a prediction. Current federal guidance already pushes home water and food storage toward two weeks, and if you live at the end of a long rural road or on an island, three days is optimistic.

Start With the Weight Budget, Not the List

Do this arithmetic before you buy anything, because it determines the entire shape of the kit.

A loaded pack that an untrained adult can carry for a few miles is about 20% of body weight. For a 160 lb (73 kg) adult that is 32 lb (14.5 kg). Treat it as a hard ceiling, not a target.

Now price the water. One US gallon of water weighs 8.34 lb (3.8 kg). Three days at the agency figure is 3 gallons — 25 lb (11.3 kg). That is 78% of the 32 lb budget, for water alone, before a single calorie, layer or light.

That number is the whole argument for splitting the kit:

• The go-bag carries one day of water — 1 gallon, 8.34 lb (3.8 kg) — plus the means to make more. A filter and chemical tablets weigh a few ounces and cover days two and three, provided there is a source. Weight saved: about 17 lb (7.7 kg), which is the rest of your kit.
• The home kit carries all of it, and more. A shelf has no weight budget. This is where the 2-week supply, the canned food, the bulk fuel and the heavy tools live.

Work the rest of the budget in the same currency. A rough, realistic go-bag for that 160 lb adult: water and treatment 9 lb (4.1 kg), food 4 lb (1.8 kg), insulation and shelter 6 lb (2.7 kg), first aid and medications 2 lb (0.9 kg), light, power and radio 2 lb (0.9 kg), sanitation and hygiene 2 lb (0.9 kg), documents, cash and tools 2 lb (0.9 kg), pack itself 3 lb (1.4 kg). That totals 30 lb (13.6 kg) and leaves 2 lb (0.9 kg) of slack you will absolutely use.

Smaller adults get smaller budgets — a 120 lb (54 kg) adult is capped near 24 lb (11 kg) — which means a household distributes load rather than duplicating it. Children carry their own snacks, water and light and nothing structural. Assume any child under about 10 may need carrying, which removes an adult's pack capacity entirely.

If you never weigh the finished bag, you have not built a kit. You have built a cupboard.

Water: One Day Carried, Two Weeks Stored, and How to Make More

Store one gallon (3.8 L) per person per day. Three days for a bag you evacuate with; two weeks on the shelf at home. Add more for hot climates, illness, pregnancy, nursing and anyone with a medical condition that drives fluid loss. Pets need their own allowance — a rough planning figure is about 1 oz of water per pound of body weight per day (65 mL per kg), so a 50 lb (23 kg) dog is around 0.4 gallons (1.5 L).

Containers. Use commercially bottled water, or food-grade containers you have sanitised. Do not reuse milk or juice jugs: the residual proteins and sugars are impossible to fully remove and the seams fail in storage. Replace self-filled tap water every six months. Store off concrete, out of sunlight, and away from gasoline, solvents and pesticides — plastic is permeable to vapours.

Making doubtful water safe. Three methods, ranked by what they actually remove, per the EPA's emergency disinfection guidance:

• Boiling is the most reliable. Bring water to a rolling boil for 1 minute. Above 6,500 ft (2,000 m), boil for 3 minutes. Boiling kills bacteria, viruses and protozoa. It does not remove chemical contamination, fuel, or heavy metals — and it concentrates them.
• Unscented household bleach, when you cannot boil. For bleach labelled 5–9% sodium hypochlorite: 2 drops per quart or litre, 8 drops per gallon, or ½ teaspoon per 5 gallons of clear water. Stir, then let it stand 30 minutes. The water should have a slight chlorine smell; if it does not, repeat the dose and wait another 15 minutes. Double the dose for water that is cloudy, coloured or very cold. Read your own bottle — concentrations vary, and the dose changes with them. Filter cloudy water through a clean cloth or let it settle first.
• Filters vary enormously and most do not stop viruses. A filter rated for bacteria and protozoa is not a virus barrier unless the label says so. Check the label, not the marketing.

The full treatment comparison, including what to do when the tap is running but under a boil-water notice, is in how much water to store per person.

One more source people forget: your water heater typically holds 30–50 gallons (115–190 L) of drinkable water, and toilet tanks — the tank, not the bowl — hold a few gallons of clean water if you have not used tank cleaning tablets. Know where the heater's drain valve is before you need it.

Food: Calories You Will Eat Cold

The test for 72-hour food is narrow: no cooking, no refrigeration, no added water, opened with one hand. Anything that fails that test belongs on the home shelf, not in the bag.

Plan on roughly 2,000 kcal per adult per day as a working baseline. Cold weather, hard physical work and carrying a pack push it well above that; sitting in a dark apartment pushes it below. Children need less by volume but eat more often.

The arithmetic that decides your pack:

• Calorie-dense food — nuts, nut butters, oil-rich bars — runs around 100 kcal per ounce. 2,000 kcal is about 20 oz (570 g) per day, so three days is 3.75 lb (1.7 kg).
• Mixed bars, crackers, dried fruit and jerky run nearer 60 kcal per ounce. Same 2,000 kcal now costs 33 oz (940 g) per day — 6.3 lb (2.9 kg) for three days.
• Canned food, counting the can and the water in it, runs about 25–40 kcal per ounce. Three days of calories that way is 10–15 lb (4.5–6.8 kg) per person. Excellent on a shelf. Wrong in a pack.

That 2.5 lb (1.1 kg) gap between the dense and the mixed option is a headlamp, a water filter and a spare fleece. It is worth optimising.

Buy food your household already eats. Rotation only happens with food people want, and an unrotated kit is a kit full of expired food. Include something with salt and something sweet — appetite collapses under stress, and palatable calories get eaten while worthy ones do not. Pack a manual can opener even if nothing in the bag needs one, because the home shelf does.

When the power goes out, the fridge is a clock. FoodSafety.gov gives the numbers: an unopened refrigerator holds food safe for about 4 hours; a full freezer for about 48 hours; a half-full freezer for about 24 hours. Perishable food held above 40 °F (4 °C) for more than 2 hours should be discarded. Keep an appliance thermometer in both compartments so the decision is a reading, not a guess. Never taste food to check it.

The full rotating-pantry build, including calorie and protein targets and the storage temperatures that decide shelf life, is in emergency food storage: a 30-day pantry plan.

Light, Power and Information

Light: one per person, hands-free, plus a spare. A headlamp beats a flashlight because it leaves both hands free for a child, a door or a wound. A shared lantern fails the moment two people need to be in different rooms. Buy a spare light rather than a brighter one — brightness is the specification that matters least in a house.

Standardise on one battery chemistry across headlamps, radio and lantern. One spare set then covers every device. Lithium AA cells cost more but store far longer and hold voltage much better below freezing; alkalines are cheaper and are the ones that leak and destroy the contacts in a device left in a drawer for two years. Store spares outside the devices.

Information: a radio that receives NOAA Weather Radio. Battery or hand-crank, and check it receives your local transmitter from where you would actually shelter. Alerts, watches, warnings and evacuation instructions come from the National Weather Service and your local emergency management office. Enable Wireless Emergency Alerts on every phone in the house. Carry a paper map of your area with two evacuation routes marked — the second one for when the first is closed.

Phone power, with the arithmetic done honestly. Power bank capacity is printed at cell voltage, not at the 5 V it delivers. A "10,000 mAh" bank holds about 37 Wh (10 Ah × 3.7 V). After the step-up conversion and cable losses you should expect roughly 25 Wh delivered. A typical modern phone battery is 15–20 Wh. So that bank is one and a half phone charges, not the three on the box. Two phones for three days needs a bank in the 20,000 mAh (74 Wh) class, or a way to recharge it.

A small solar panel is a slow trickle, not a generator, and it does nothing under the heavy overcast that accompanies most storms. Treat it as a bonus.

If you run a generator, this part is not negotiable. Carbon monoxide from portable generators kills people every year, and it kills them indoors. Run a generator outdoors only, at least 20 ft (6 m) from your home and from every window, door and vent, never in a garage, basement or crawl space — even with the door open. Install battery-backed CO alarms on every level of the home. The CDC and Ready.gov both publish this guidance and both publish it in the same words, because the failure mode is fatal and fast. Sizing a battery station or generator to your real measured load is covered in backup power for a home outage.

Warmth and Shelter: The Function Most Kits Get Wrong

A powered-down house in winter does not stay at room temperature. It drifts toward the outdoor temperature at a rate set by insulation and wind, and you will be sitting still in it, generating almost no heat. Most kit lists cover this with a foil emergency blanket and move on.

What actually covers the function, per person:

• One complete insulating layer you are not currently wearing — fleece or synthetic puffy. Wool or synthetic, never cotton. Wet cotton conducts heat away from you and keeps doing it until it dries, which indoors and unheated may be never.
• A hat and gloves. Cheap, light, disproportionately effective.
• Two pairs of wool or synthetic socks, kept dry and sealed in a bag. Dry socks are a morale item as much as a thermal one.
• Rain shell, hood included. Staying dry is cheaper than getting warm again.
• A bivy sack or a proper emergency blanket per person, not one for the family. The thin foil sheets tear; the heavier reflective bivies survive a night.
• Sturdy closed shoes by the bed. Broken glass is the most common injury after a structural event, and the most avoidable.

For sheltering in place rather than evacuating, Ready.gov recommends plastic sheeting and duct tape to seal a single interior room against outside air contamination. Size it before the day: measure the doors, windows and vents of the room you would use, cut the sheeting to size now, label each piece, and store them rolled together with the tape. Sealing a room is explicitly a short-duration measure — a sealed room accumulates your own exhaled CO₂ — so follow official instructions on when to seal and when to ventilate.

Heating a room with anything that burns is where people die. No charcoal, no camp stove, no unvented fuel heater indoors. If you use a fuel-burning heater rated for indoor use, follow the manufacturer's ventilation requirement exactly and keep a CO alarm in the room. This is safety-critical and depends on your appliance and local code; see the disclaimer.

First Aid, Medications and the Documents Folder

Medications first, because nothing else in the kit substitutes for them. Aim to keep a week's supply of every prescription on hand, along with the exact dose, strength and prescribing information written down — not just the pill. Whether you can build a buffer at all depends on your prescriber, your insurer and your jurisdiction's refill rules, so ask your pharmacist how to do it legally where you live rather than skipping doses to bank pills. Refrigerated medications such as insulin need a cooling plan and a written temperature limit from the manufacturer. Powered medical equipment needs its own power plan; in many areas the utility keeps a register of medically dependent customers, which is worth joining before you need it. This is medical and jurisdiction-dependent territory — see the disclaimer.

Also pack spare glasses or contacts and solution, hearing aid batteries, and anything else without which a family member cannot function.

The first aid kit should be built around what actually happens, not around a red bag with 200 identical plasters. Cuts, burns, sprains, blisters, headaches, upset stomachs and allergic reactions account for nearly everything. A useful kit is heavy on gauze, tape, irrigation, gloves and the medications you take anyway. Component-by-component build and the training that makes each item worth carrying is in the wilderness first aid kit.

The kit is not the skill. Adult CPR is delivered at 100–120 compressions per minute, at least 2 inches (5 cm) deep for an adult, allowing full chest recoil. You cannot learn that from a paragraph. Take a hands-on class from the American Red Cross or an equivalent provider; a half-day course outperforms a thousand dollars of gear.

The documents folder goes in a sealed waterproof bag and takes minutes to assemble:

• Photo ID, insurance policies with policy numbers and claims phone numbers, deeds or lease, vehicle registration
• Medication and allergy list for each person, immunisation records, physician and pharmacy contacts
• A printed contact card per person, including one out-of-area contact — local circuits saturate first, and a text to a distant number often gets through when a local call will not
• Photographs of each room of the house for insurance purposes
• An encrypted copy of all of it on a USB drive or in cloud storage, because paper burns

Cash, in small bills. Card readers and ATMs need power and a network. A few hundred dollars in fives, tens and twenties covers fuel, a room or a meal when the terminals are down. Nobody makes change in an outage.

Sanitation: The Function Everyone Skips

If the water main loses pressure or the sewer backs up, your toilet stops being a toilet. Three days of a household of four with no sanitation plan is a genuine health problem, and the illness that follows — hand-to-mouth gastrointestinal infection — is both the most likely thing to happen to you and the most preventable.

The minimum kit, most of it from Ready.gov's own list:

• Heavy-duty garbage bags and plastic ties, plus moist towelettes, for personal sanitation
• Two 5-gallon (19 L) buckets with a snap-on toilet seat lid: one for solids, one for liquids. Line the solids bucket with a bag and add an absorbent each use — cat litter, sawdust or wood pellets — to control odour and moisture. Tie off and store outside in a sealed container until collection resumes.
• Soap and water for handwashing, which is the highest-yield item here. Hand sanitiser with at least 60% alcohol is the backup, and it is a backup: it works poorly on visibly soiled hands and is less effective against some gastrointestinal viruses. The CDC guidance is soap and running water first.
• Disinfectant wipes or a bleach solution for surfaces, kept separate from the bleach you dose drinking water with, and clearly labelled.
• Menstrual and continence supplies, and infant nappies, in quantities that match actual use rather than a token pack.

Do not flush until you know the sewer is working. A backup into the house converts an inconvenience into an evacuation.

Part of the half-gallon (1.9 L) per person per day of non-drinking water is for exactly this. If you cut the water allowance to save weight, you are cutting handwashing, and handwashing is what keeps three uncomfortable days from becoming a week of illness.

Two Kits, Three Locations, and the People Who Need Extras

The home kit (stay). No weight limit. Two weeks of water, the deep pantry, the bulk batteries, the tools, the sanitation buckets, the heavy first aid stock. Store it where you can reach it in the dark without moving a car — a hall cupboard beats a garage shelf, and a garage or attic beats nothing but cooks medications and batteries through summer temperature swings.

The go-bag (leave). One per person, at the weight budget from section two, by the door you would actually leave from. Packed, closed, and not raided for camping trips. Attach a laminated go-list to the strap covering the four things that cannot live in the bag: medications, phone and charger, glasses, keys and wallet.

The vehicle kit. You may be at work when it happens. Water, food, a light, a blanket, sturdy shoes, a paper map, a phone cable, and walking-capable footwear if you commute in dress shoes. Rotate the water in summer and remember that heat degrades medications and batteries in a parked car.

Household members who need more than the standard build:

• Infants: formula, bottles, nappies, wipes, a change of clothes, and enough of whatever they will actually take. Formula is not improvisable.
• Older adults and anyone with mobility or medical dependency: spare mobility aids, a written medication and equipment list, powered-device backup, and an agreement with a neighbour on who checks on whom.
• Pets: water, food, bowls, leash, carrier, current vaccination records, and a photo of you with the animal in case you are separated. Many public shelters accept only service animals, so know your alternatives now rather than at the door.
• Children: their own small pack with snacks, water, a light and one comfort item. A child with a job and a torch is a child who is not panicking.

Household plans — who calls whom, where you meet, who has a key — are covered across emergency preparedness, and start here is the shortest path if you are building from zero.

Drills, With Explicit Pass Conditions

A kit is a hypothesis. These four drills test it. Write the date and the result on the inventory card in the bag; a failed drill in daylight is free.

Drill 1 — The 10-minute walkout. At night, with the lights off and no advance warning to the household, call the drill. Everyone collects their own bag, adds the four go-list items, gets shoes on, secures pets and assembles outside at the meeting point. Pass: every person and every bag is outside within 10 minutes, and nothing on the written go-list is missing. Repeat until it passes twice in a row. If it takes 25 minutes, the problem is almost never speed — it is that something on the list lives somewhere nobody can find in the dark.

Drill 2 — The dark evening. Turn off the main breaker at dusk on a weekend and leave it off for 3 hours. Use only the kit. Do not open the refrigerator. Pass: every occupied room had usable light the whole time; a meal was prepared and eaten from kit food; the radio pulled a weather broadcast; every phone finished above 50%; and nobody opened the fridge. Any "we'll just grab it from the kitchen" moment is a failure — write down what was grabbed and add it to the kit.

Drill 3 — The stranger test. Hand a bag to the household member who did not pack it. Say nothing. Pass: within 5 minutes, without instruction, they locate and operate the light, the radio, the water treatment and the can opener, and can state where the medications and documents are. Gear only one person understands is gear the household does not have.

Drill 4 — The water dose check. Take the actual bleach bottle and the actual container you have stored. Read the sodium hypochlorite percentage off the label. Pass: you state the correct dose for that concentration and that container volume, and the 30-minute wait, from the label alone — and the dropper or measuring spoon is physically in the kit. For 5–9% bleach the answer is 8 drops per gallon of clear water, doubled if it is cloudy or very cold, per the EPA. If you had to look it up, tape the dose to the bottle.

Bonus, and the one people avoid: load the bag to its final weight and walk 3 miles (5 km) with it. Pass if you finish without adjusting the load more than twice and without a blister. Everything that annoyed you in the first mile will be intolerable in the fifth.

We publish the conditions and pass marks for every protocol we use, including the ones our gear testing fails — see how we test.

Common Mistakes and Failure Modes

Ranked roughly by how often they turn a prepared household into an unprepared one.

• Buying a pre-packed kit and never opening it. The commercial bag is a starting inventory at best. It contains no prescriptions, no documents, no cash, nothing sized to your family, and often a foil blanket standing in for insulation. Open it, weigh it, and rebuild it.
• One kit for the whole family. If the kit is in the car and you are at work, the household has nothing. Redundancy beats completeness.
• Storing it where you cannot get to it. Behind the car, in the loft, under the spare room bed, at the back of the garage. The kit must be reachable in the dark, in under a minute, by the shortest household member.
• Alkaline batteries left inside devices. They leak, corrode the contacts and kill the light. Store cells outside the device, and check them every six months.
• Water in reused milk or juice jugs. Residual sugars and proteins feed bacterial growth and the seams split. Use food-grade containers or commercially bottled water, and replace self-filled tap water every six months.
• No manual can opener. Endlessly repeated, still true.
• Cotton. Jeans, hoodies, cotton socks. Once wet, they are a heat leak you cannot switch off.
• Treating a filter as a virus barrier. Unless the label states virus removal or reduction, it does not do it. Boiling does.
• Running a generator or any fuel burner indoors, in a garage, or too close to a window. Twenty feet (6 m), outdoors, always, with CO alarms inside. This one kills.
• Only a phone. Documents, maps, contact numbers and the torch all on a device with a 15 Wh battery and no network. Print the critical parts.
• No cash. Terminals and ATMs are network devices.
• Weight creep. The bag grows by one plausible item a month until it cannot be carried. Re-weigh at every six-month check and remove something.
• First use during the emergency. The stove, the filter, the radio, the tourniquet — if the first time you operate it is during an outage, you own an object, not a capability.
• Skipping the medical plan. Prescriptions, refrigerated drugs, powered equipment, spare glasses. The hardest gap to close and the one most likely to force you out of your own home.

Maintenance: A 20-Minute Check, Twice a Year

Kits decay quietly. Put the check on a fixed trigger you cannot forget — the twice-yearly clock change works well — and give it 20 minutes.

Every six months:

• Water: replace self-filled containers; check commercial bottles for dates, bulges and leaks.
• Food: pull anything within six months of its date and eat it; replace it. Rotation is the whole point of buying food you like.
• Batteries: test every light and the radio. Replace spares on a schedule rather than on failure. Inspect for leakage.
• Power bank: charge it to full. Lithium cells self-discharge, and a bank that has sat for a year may be empty when you need it.
• Medications: check expiry dates, refresh the buffer, confirm the written dose list still matches what the household actually takes.
• Clothing: re-size everything belonging to a child. Children outgrow a kit faster than food expires.
• Documents: update insurance, contacts, photos of the house, and the out-of-area contact number.
• Cash: confirm it is still there and still in small bills.
• Weight: re-weigh each pack against its 20%-of-body-weight ceiling and remove whatever crept in.
• Run one drill. Rotate which one.

Once a year: unpack completely onto the floor, lay everything out, and put back only what you can justify against one of the six functions. Write the date and your initials on the inventory card inside the bag, along with the result of the last drill. A kit with a dated card is a kit somebody is responsible for.

On how this guide is sourced. Quantities, disinfection ratios, food-safety windows and carbon monoxide distances here are taken from published guidance by Ready.gov, FEMA, the CDC, the EPA, FoodSafety.gov, the National Weather Service and the American Red Cross, and linked at the point of use so you can check them against the current version rather than against us. Our own gear work is field testing with stated conditions, sample sizes and failure points, published under how we test and our editorial standards; where we have not tested something, we say so rather than imply otherwise.

Medical decisions, prescription supply, utility shutoffs, indoor fuel burning and building code all vary by jurisdiction and by your specific circumstances. This guide is not a substitute for training or professional advice — see the disclaimer. The single highest-return upgrade to any kit remains a hands-on first aid course, not another purchase.