# Preppers

> A free offline library for when the internet or power is out. Emergency cards, WikEM, WikiMed, repair guides, Stack Exchange, Wikipedia and books from Kiwix, picked to fit your space. No account, no tracking.

Web page: https://davidewins.com/preppers

A library for when the internet or the power goes out. Pick what your household needs, download it once, and read it with no signal.

Free and open source. No account, no tracking, and nothing leaves your device after setup. The content comes from Kiwix, the offline Wikipedia project.

## How it works

- **Setup**: four questions (where you live, who you look after, what you want, how much space), then a recommended list with a storage meter. Presets: Essentials, Family, Everything that fits. Or talk it through with Claude instead.
- **Downloads**: each pack is a ZIM file, downloaded by your browser straight from Kiwix's mirror into private storage on your device, checked piece by piece against Kiwix's checksums, with pause and resume.
- **Offline**: a service worker keeps the page, the cards and the reader working with no connection.
- **Search**: title search across every downloaded pack.

Machine-readable catalogue: [/preppers/catalogue.json](https://davidewins.com/preppers/catalogue.json)

## Packs

- **Emergency cards** (built in): CPR, choking, bleeding, burns, water and more as numbered steps in large type. Works offline from the first visit. Source: [Written for this site from NHS, HSE, Red Cross, CDC and FEMA guidance](https://davidewins.com/preppers). Licence: [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).
- **WikEM** (347 MB, 2026-07-24): Emergency medicine reference written by emergency doctors. Text only. Source: [WikEM](https://wikem.org). Licence: [CC BY-SA 4.0](https://wikem.org/wiki/WikEM:Copyrights).
- **WikiMed (intros)** (163 MB, 2026-04-11): Wikipedia’s medical articles, introductions only. Source: [Wikipedia via Kiwix](https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **WikiMed (text)** (862 MB, 2026-04-11): Wikipedia’s medical articles in full, no images. Source: [Wikipedia via Kiwix](https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **WikiMed (with images)** (2.2 GB, 2026-04-11): Wikipedia’s medical articles in full, with diagrams and photos. Source: [Wikipedia via Kiwix](https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Ready.gov** (2.4 GB, 2024-12-03): FEMA’s guides for floods, storms, outages, shelter and go-bags. Source: [FEMA](https://www.ready.gov). Licence: [US government work, public domain in the US](https://www.fema.gov/about/website-information).
- **US Army publications** (8.2 GB, 2024-12-06): Field manuals and technical publications, including survival, first aid and field sanitation. Source: [Army Publishing Directorate](https://armypubs.army.mil). Licence: [US government work, public domain in the US](https://armypubs.army.mil).
- **The Great Outdoors Q&A** (141 MB, 2026-08-04): Camping, hiking, fire, shelter and navigation answers. Source: [Stack Exchange](https://outdoors.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Amateur Radio Q&A** (76 MB, 2026-08-02): Radios, antennas and licences, for when phones are down. Source: [Stack Exchange](https://ham.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **iFixit** (3.6 GB, 2025-12-21): Step-by-step repair guides for phones, appliances, cars and tools. Source: [iFixit](https://www.ifixit.com). Licence: [CC BY-NC-SA 3.0 (non-commercial)](https://www.ifixit.com/Info/Licensing).
- **Home Improvement Q&A** (2.1 GB, 2026-08-03): Plumbing, wiring, heating and building answers. Source: [Stack Exchange](https://diy.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Electronics Q&A** (4.2 GB, 2026-08-01): Circuits, batteries, solar and power answers. Source: [Stack Exchange](https://electronics.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Gardening Q&A** (927 MB, 2026-08-01): Growing vegetables, soil, pests and plant care. Source: [Stack Exchange](https://gardening.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Sustainable Living Q&A** (28 MB, 2026-08-06): Compost, rainwater, solar and living on less. Source: [Stack Exchange](https://sustainability.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Cooking Q&A** (237 MB, 2026-07-31): Food safety, storage, preserving and cooking answers. Source: [Stack Exchange](https://cooking.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Pets Q&A** (87 MB, 2026-08-04): Care, feeding and health answers for dogs, cats and other pets. Source: [Stack Exchange](https://pets.stackexchange.com). Licence: [CC BY-SA (2.5, 3.0 or 4.0 by post date)](https://stackoverflow.com/help/licensing).
- **Appropedia** (582 MB, 2026-02-26): Low-cost technology: water filters, cookstoves, solar and shelter. Source: [Appropedia](https://www.appropedia.org). Licence: [CC BY-SA 4.0](https://www.appropedia.org/Appropedia:Copyrights).
- **CIA World Factbook (2020)** (407 MB, 2026-02-06): Every country’s geography, people, government and economy. Source: [Central Intelligence Agency](https://www.cia.gov/the-world-factbook/). Licence: [US government work, public domain in the US](https://www.cia.gov/the-world-factbook/about/copyright-and-contributors/).
- **Wikipedia, top articles (intros)** (297 MB, 2026-09-14): 703,608 articles. Each article’s introduction only, no images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikipedia, top articles (text)** (2.7 GB, 2026-09-14): 877,754 articles. Full text, no images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikipedia, top articles (with images)** (7.0 GB, 2026-09-14): 877,754 articles. Full text with images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikipedia, every article (intros)** (14 GB, 2026-09-09): 18,095,848 articles. Each article’s introduction only, no images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikipedia, every article (text)** (53 GB, 2026-06-17): 19,191,219 articles. Full text, no images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikipedia, every article (with images)** (127 GB, 2026-08-25): 21,673,012 articles. Full text with images. Source: [Wikipedia](https://en.wikipedia.org). Licence: [CC BY-SA 4.0](https://en.wikipedia.org/wiki/Wikipedia:Copyrights).
- **Wikibooks** (3.5 GB, 2026-04-27): Open textbooks and manuals, from first aid to cookbooks. Text only. Source: [Wikibooks](https://en.wikibooks.org). Licence: [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/).
- **Project Gutenberg: agriculture** (4.5 GB, 2026-03-06): Public domain books on farming, gardening, animals and food. Source: [Project Gutenberg](https://www.gutenberg.org). Licence: [Public domain in the US](https://www.gutenberg.org/policy/license.html).
- **Project Gutenberg: English literature** (16 GB, 2026-03-05): Public domain novels, plays and poetry from British and Irish writers. Source: [Project Gutenberg](https://www.gutenberg.org). Licence: [Public domain in the US](https://www.gutenberg.org/policy/license.html).
- **LibreTexts: school** (370 MB, 2026-01-16): Open school textbooks for maths, science and reading. Source: [LibreTexts](https://k12.libretexts.org). Licence: [Varies by page, shown on each page (mostly Creative Commons)](https://libretexts.org).
- **LibreTexts: mathematics** (831 MB, 2026-01-16): Open university maths textbooks. Source: [LibreTexts](https://math.libretexts.org). Licence: [Varies by page, shown on each page (mostly Creative Commons)](https://libretexts.org).
- **LibreTexts: medicine** (1.2 GB, 2025-01-16): Open textbooks on anatomy, nursing and pharmacology. Source: [LibreTexts](https://med.libretexts.org). Licence: [Varies by page, shown on each page (mostly Creative Commons)](https://libretexts.org).
- **PhET simulations** (soon, in the native app) (109 MB, 2026-08-25): Interactive science and maths simulations for kids. Source: [University of Colorado Boulder](https://phet.colorado.edu). Licence: [CC BY 4.0](https://phet.colorado.edu/en/licensing).
- **Map of the United Kingdom** (soon, in the native app) (1.9 GB, 2026-06-12): OpenStreetMap of the United Kingdom with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).
- **Map of the United States** (soon, in the native app) (17 GB, 2026-06-13): OpenStreetMap of the United States with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).
- **Map of Canada** (soon, in the native app) (11 GB, 2026-06-13): OpenStreetMap of Canada with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).
- **Map of Australia** (soon, in the native app) (1.9 GB, 2026-06-08): OpenStreetMap of Australia with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).
- **Map of New Zealand** (soon, in the native app) (4.0 GB, 2026-06-08): OpenStreetMap of New Zealand with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).
- **Map of Europe** (soon, in the native app) (27 GB, 2026-08-20): OpenStreetMap of Europe with place search. Source: [OpenStreetMap via openZIM](https://www.openstreetmap.org). Licence: [ODbL (OpenStreetMap data)](https://www.openstreetmap.org/copyright).

## Coming next

- **Bookmarks**: Save an article to come back to.
- **Highlights and notes**: Mark a passage and write beside it.
- **Full-text search**: Search inside articles, not just titles.
- **Offline maps and PhET simulations**: in the native app. They need scripts, and no pack content runs scripts on this site.

### Not in the catalogue

- **MedlinePlus**: The Kiwix copy mixes public domain pages with the A.D.A.M. Medical Encyclopedia, which NLM licenses only for use on MedlinePlus.
- **Standard Ebooks and OpenStax**: Not in the Kiwix catalogue yet. Project Gutenberg, LibreTexts and Wikibooks cover the gap.
- **A map of Ireland on its own**: Kiwix has no Ireland-only map. The UK map covers Northern Ireland; the Europe map covers the whole island.

## Emergency cards

These cards are not medical training and do not replace a first aid course. In an emergency, call the emergency services first.

### CPR

An adult is unresponsive and not breathing normally.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) straight away, with the phone on speaker.

1. Make sure the area is safe, then shake their shoulders and shout to see if they respond.
2. Tilt the head back and look and listen for breathing. Gasping or noisy, irregular breaths are not normal breathing.
3. Call the emergency number, put the phone on speaker and say the person has collapsed and is not responding.
4. Send someone to fetch a defibrillator (AED). The call handler can tell you where the nearest one is.
5. Kneel beside them on a firm surface. Put the heel of one hand mid-chest, your other hand on top.
6. Keep your arms straight, shoulders over your hands, and push hard and fast: at least 2 inches deep, 100 to 120 a minute.
7. Let the chest come all the way back up after each push.
8. Keep pushing without stopping. If you are not trained in rescue breaths, give compressions only.
9. When the AED arrives, switch it on and follow its instructions. Carry on until help takes over or they show signs of life.

- Do not give up if you see no change. Swap with someone every minute or two if you can.

Sources: [Resuscitation Council UK: How to do CPR](https://www.resus.org.uk/public-resource/how-do-cpr), [American Red Cross: Hands-Only CPR](https://www.redcross.org/take-a-class/cpr/performing-cpr/hands-only-cpr), [British Red Cross: Unresponsive and not breathing](https://www.redcross.org.uk/first-aid/learn-first-aid/unresponsive-and-not-breathing).

### Choking

An adult is choking and cannot clear it by coughing.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) if back blows and thrusts have not cleared it.

1. If they can cough, tell them to keep coughing and stay with them.
2. If they cannot cough, speak or breathe, stand slightly behind them and lean them well forward.
3. Give up to 5 firm blows between the shoulder blades with the heel of your hand.
4. If they are still choking, stand behind them, wrap your arms round their waist and make a fist just above the belly button.
5. Cover your fist with your other hand and pull sharply inwards and upwards, up to 5 times.
6. If it has not cleared, call the emergency number, then keep alternating 5 back blows and 5 abdominal thrusts.
7. For a pregnant person, or someone too large to reach round, give chest thrusts instead of abdominal thrusts.
8. If they become unresponsive, lower them gently to the ground and start CPR.

- Do not sweep inside the mouth with a finger unless you can see the object.
- Do not leave someone who is coughing on their own. Watch them in case it gets worse.

Sources: [British Red Cross: Choking](https://www.redcross.org.uk/first-aid/learn-first-aid/choking), [American Red Cross: Adult and child choking](https://www.redcross.org/take-a-class/resources/learn-first-aid/adult-child-choking).

### Severe bleeding

Blood is spurting or flowing heavily and will not stop.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) straight away.

1. Press firmly on the wound with a clean dressing or whatever cloth you have.
2. Call the emergency number and follow what the operator tells you.
3. Keep steady, firm pressure on the wound until the bleeding stops or help arrives.
4. If blood soaks through, swap in a fresh pad and keep pressing hard.
5. If something is stuck in the wound, leave it in and press around it instead.
6. Use a tourniquet on a bleeding limb only if you are trained and one is available.
7. If they look pale, cold or dizzy, lie them down, raise their feet and keep them warm.
8. Once the bleeding stops, bandage firmly over the dressing and watch for it starting again.

- Do not pull out an object stuck in the wound.
- Do not wash a wound that is bleeding heavily.

Sources: [British Red Cross: Bleeding heavily](https://www.redcross.org.uk/first-aid/learn-first-aid/bleeding-heavily), [American Red Cross: Life-threatening external bleeding](https://www.redcross.org/take-a-class/resources/learn-first-aid/bleeding-life-threatening-external).

### Burns

Someone has a burn or scald from heat, flame or hot liquid.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) if the burn is large, deep, on the face or genitals, or chemical or electrical.

1. Cool the burn under cool running water for 20 minutes, starting as soon as you can.
2. If there is no tap, use cool bottled water or another cold drink.
3. Take off clothing and jewellery near the burn, but leave anything that is stuck to it.
4. After cooling, lay cling film over the burn, or use a clean plastic bag.
5. Give painkillers such as paracetamol or ibuprofen if needed.
6. Get medical help if you are unsure, or if the person is a baby or child.

- Do not put butter, cream, oil or toothpaste on a burn.
- Do not use sticky plasters or dressings, and do not burst blisters.
- Do not wrap cling film tightly round the burn.
- Do not put the whole body in a cold bath or shower, as it can cause hypothermia.

Sources: [NHS: Burns and scalds](https://www.nhs.uk/conditions/burns-and-scalds/), [British Red Cross: Burns](https://www.redcross.org.uk/first-aid/learn-first-aid/burns).

### Hypothermia

Someone is very cold, shivering, pale, slurring, drowsy or confused.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) if you think someone has hypothermia.

1. Get them indoors or into shelter as fast as you can.
2. Put something between them and the ground if they are lying outside.
3. Take off wet clothing and get them into dry clothes.
4. Wrap them in blankets, a sleeping bag or dry towels, and cover their head.
5. If they are fully awake, give a warm, non-alcoholic drink and something sugary such as chocolate.
6. Keep them talking and stay with them until help arrives.

- Do not warm them with a hot bath or a heat lamp.
- Do not rub their arms, legs, hands or feet.
- Do not give them alcohol.

Sources: [NHS: Hypothermia](https://www.nhs.uk/conditions/hypothermia/), [British Red Cross: Hypothermia](https://www.redcross.org.uk/first-aid/learn-first-aid/hypothermia).

### Making water safe

Tap water is off or unsafe and you need water to drink.

1. If the water is cloudy, let it settle, then filter it through a clean cloth, paper towel or coffee filter.
2. Best option: bring clear water to a rolling boil for 1 minute (3 minutes above 6,500 feet), then let it cool.
3. If you cannot boil, use plain unscented household bleach of 5 to 9% sodium hypochlorite, less than a year old.
4. Add 2 drops per litre (or quart), or 8 drops per US gallon.
5. Double the dose if the water is cloudy, coloured or very cold.
6. Stir well and leave it to stand for at least 30 minutes before drinking.
7. It should smell faintly of chlorine. If not, add the same dose again and wait another 15 minutes.
8. Store treated water in clean containers with tight lids.

- Do not use scented, colour-safe or bleach with added cleaners.
- Do not rely on boiling or bleach for water polluted with fuel or chemicals. Find another source.
- Do not drink water from radiators or the heating boiler.

Sources: [CDC: How to make water safe in an emergency](https://www.cdc.gov/water-emergency/about/index.html), [US EPA: Emergency disinfection of drinking water](https://www.epa.gov/ground-water-and-drinking-water/emergency-disinfection-drinking-water).

### Food in a power cut

The power is off and you have food in the fridge or freezer.

1. Keep the fridge and freezer doors shut as much as you can.
2. A closed fridge keeps food safe for about 4 hours.
3. A full freezer holds its temperature for about 48 hours, a half-full one for about 24 hours.
4. Use appliance thermometers. The fridge should stay at 40°F (4°C) or below.
5. Use coolers with ice to keep fridge food cold if needed.
6. Throw out perishable fridge food after 4 hours without power or a cold source.
7. Throw out any food that smells, looks or feels unusual.
8. Thawed food with ice crystals, or still at 40°F (4°C) or below, can be refrozen or cooked.

- Do not taste food to find out if it is safe. When in doubt, throw it out.

Sources: [CDC: Keep food safe after a disaster or emergency](https://www.cdc.gov/food-safety/foods/keep-food-safe-after-emergency.html), [Ready.gov: Power outages](https://www.ready.gov/power-outages).

### Carbon monoxide

A CO alarm sounds, or people get headaches, dizziness, sickness or confusion indoors.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) if anyone is unconscious, confused or struggling to breathe.

1. Stop using fuel-burning appliances and switch them off if you can.
2. Open doors and windows on your way out.
3. Get everyone outside into fresh air straight away.
4. Stay out until the emergency services say it is safe to go back in.
5. Report a suspected gas leak: Ireland 1800 20 50 50, UK 0800 111 999.
6. Get medical advice even if symptoms ease. Fresh air alone does not treat CO poisoning.

- Do not run a generator indoors or in a garage. Keep it outside, more than 20 feet from doors, windows and vents.
- Do not heat your home with a gas oven or cooker.
- Do not use a barbecue or camping stove indoors or in a tent.
- Do not drive yourself to hospital.

Sources: [HSE: Carbon monoxide poisoning](https://www2.hse.ie/conditions/carbon-monoxide-poisoning/), [NHS: Carbon monoxide poisoning](https://www.nhs.uk/conditions/carbon-monoxide-poisoning/), [CDC: Carbon monoxide poisoning basics](https://www.cdc.gov/carbon-monoxide/about/index.html).

### Go-bag

Pack this before an emergency so you can leave home in minutes.

1. Pack water: about one US gallon (3.8 litres) per person per day, for at least 3 days.
2. Pack at least 3 days of non-perishable, easy-to-prepare food and a manual can opener.
3. Add a torch, a battery or hand-crank radio, and spare batteries.
4. Add a first aid kit and a 7-day supply of medicines.
5. Add a phone charger and backup battery, some cash and local maps.
6. Pack copies of key documents: ID, proof of address, insurance papers and a list of medicines.
7. Add a whistle, dust masks, wet wipes, bin bags and cable ties.
8. Add baby or pet supplies if you need them.
9. Seal items in airtight bags and keep everything in one or two easy-to-carry containers.

Sources: [Ready.gov: Build a kit](https://www.ready.gov/kit), [American Red Cross: Survival kit supplies](https://www.redcross.org/get-help/how-to-prepare-for-emergencies/survival-kit-supplies.html).

### Heat exhaustion and heatstroke

Someone is overheated: heavy sweating, dizziness, headache, cramps or sickness.

Call 112 or 999 (Ireland, UK), 911 (US and Canada), 112 (EU) at once for signs of heatstroke, or if not better after 30 minutes.

1. Move them to a cool place and let them rest.
2. Take off clothing they do not need.
3. Give plenty of water, or a sports drink or rehydration drink.
4. Cool their skin with cool water and fan them. Wrapped cold packs can go in the armpits or on the neck.
5. Heat exhaustion should ease within 30 minutes. Stay with them until they recover.
6. Heatstroke signs: very high temperature, hot skin that has stopped sweating, confusion, fast breathing, a fit or collapse.
7. For heatstroke, call for help, then wrap them in a cold wet sheet and keep pouring cold water over it.
8. If there is no sheet, fan them or sponge them with cool water until help arrives.
9. If they become unresponsive, check their breathing and start CPR if there are no signs of life.

- Do not give drinks if they are vomiting or not fully alert.
- Do not drive yourself to A&E.

Sources: [NHS: Heat exhaustion and heatstroke](https://www.nhs.uk/conditions/heat-exhaustion-heatstroke/), [British Red Cross: Heatstroke](https://www.redcross.org.uk/first-aid/learn-first-aid/heatstroke), [American Red Cross: Heat exhaustion](https://www.redcross.org/take-a-class/resources/learn-first-aid/heat-exhaustion).

## Sources

- [Kiwix OPDS catalogue](https://opds.library.kiwix.org/catalog/v2/entries), read 2026-10-10
- [Kiwix downloads](https://download.kiwix.org/zim/), read 2026-10-10
- [openZIM file format](https://wiki.openzim.org/wiki/ZIM_file_format), read 2026-10-10
- [MDN: storage quotas and eviction](https://developer.mozilla.org/en-US/docs/Web/API/Storage_API/Storage_quotas_and_eviction_criteria), read 2026-10-10
- [WebKit: updates to storage policy](https://webkit.org/blog/14403/updates-to-storage-policy/), read 2026-10-10