A 72-hour household kit

It works if a service goes down for a few hours or a few days. The two official guides that count agree on the essentials: FEMA asks for around 3.8 litres of water per person per day for several days, non-perishable food, a battery or hand-crank radio, a torch, a first-aid kit, a whistle, a manual tin opener and documents in a waterproof container ^[400]Build A Kit — Basic Disaster Supplies KitFederal Emergency Management Agency · 2026 · official documentView source ↗Accessed on 9 September 2026. SENAPRED, which is the Chilean reference, sets two litres per person per day plus two extra, a horizon of 48 to 72 hours, cash, copies of documents and a plan adapted to the household, explicitly naming infants, people with autism spectrum disorder and pregnant women ^[956]Prepara tu Kit de EmergenciaServicio Nacional de Prevención y Respuesta ante Desastres · 2026 · official documentView source ↗Accessed on 9 September 2026.

It does not work if what you are after is protection against AI. No serious organisation in the field recommends a kit for that reason. Justify it by what actually happens where you live —earthquake, storm, prolonged outage— and the list is exactly the same.

Evidence. Civil protection consensus from two state agencies in different countries. It is not a randomised trialRandomised trialAn experiment in which chance decides who gets what is being tested and who does not, so that this is the only difference between the groups. It is the most reliable way to know whether something causes an effect.For exampleTo find out whether a fertiliser works, you draw lots for which half of the garden gets it, instead of giving it to the plants that already looked healthier. and should not be presented as one.

Cost. Low, and it decays: check expiry dates and batteries, or in three years you will have a box of things that do not work.

What it does NOT solve. What actually killed people in the Iberian blackout. A kit with candles and no carbon monoxide detector, in a house that depends on a medical device, prepares for the picturesque and leaves out the lethal ^[1105]2025 Iberian Peninsula blackoutWikipedia contributors · 2026 · webView source ↗Accessed on 9 September 2026.