The threat of tornadoes and other dangers from above is a serious matter for those living in certain areas of the U.S.

So, what do you need to keep your family safe in the event of an emergency? A survival bunker or underground shelter could mean the difference between life and death. Here’s what you should have in yours.

1. Air Ventilation

You won’t survive long underground without oxygen. Installing a reliable air ventilation system in your bunker should be your priority. You’ll need a system that will last for months and be able to withstand a storm or bomb going off. Calculate how many people will be down in the bunker and for approximately how long, then use that information to determine how much air you’ll use.

2. Water

Water is more essential for survival than food. Theoretically, a person can last three days without water and three weeks without food. Stocking your bunker with water is an area when many people come up short. FEMA recommends at least one gallon per person per day.

There’s no telling how long you might be stuck in your bunker, so it’s important to have a large cache of water. Opt for jugs or bottles of water that have been treated to last longer than what you might normally find on a grocery store shelf. Remember to switch it out every few months to make sure you have the freshest possible water when trouble arrives.

3. Food

Perishable goods have no place in a survival bunker. Instead, stock your shelves with canned foods including fruits and vegetables. Also include long-lasting snacks like MREs (Meal, Ready-to-eat). Peanut butter, crackers, and canned tuna all have long shelf lives.

4. Tools

Depending on how large your bunker is, you’ll likely have items down there that could break with constant use. Beds, appliances, and lighting could all go haywire, and you’ll need to have a way to fix them.

Since space is at a premium, consider swapping your standard toolbox with a multi-tool like the Surge. The Leatherman Surge® is one of our two largest multi-tools; a real powerhouse, built with our largest pliers, longest multi-tool blades, and easy-to-use locks.

With a multi-tool like the Surge, you will be ready to tackle any repair task needed to keep your bunker secure and your family safe.

5. Warm Clothes

It is not warm underground. You’ll need to stock some extra clothes to help get you through the cool nights unless you have a bunker built with some serious insulation. Pack clothes that will keep your temperature normal like Merino wool, and of course jackets and thick socks. Fashion isn’t really a concern, so be sure to focus on function.

6. Batteries

Batteries are going to be your lifeline if your electricity goes out, so stock up on them while you can. You’ll need them for flashlights, and for the battery-powered radio you should have on hand to keep track of what’s happening up above.

7. First Aid Kit

Even down in a storm, shelter accidents can happen, so you’ll want to be prepared. Small cuts can become infected, and there won’t be a doctor around to help you treat it. Put together a first-aid kit to keep in your bunker that includes pain relievers, antibiotics, antiseptics, and plenty of bandages. Be sure to monitor your stash, and switch out anything that is nearing its expiration date on a regular basis. A reliable pair of scissors like the Raptor® Response is an essential part of every first-aid kit. These professional-grade shears can be used to cut bandages or remove shoes and clothing in case of injury.

8. Important Documents

Keep copies of all your important documents in a safe down in your shelter. Photo identification, passports, birth certificates, and insurance forms are all a must to make life easier in the aftermath. If your house gets blown away in a tornado or another disaster, you’ll want proof on hand that you’re covered.