Your guide to a better future

Hurricane Fiona has left most of Puerto Rico without power. But those affected can act fast to prevent their food from going bad during the outage.

Alison DeNisco Rayome is a managing editor at CNET, now covering home topics after writing about services and software. Alison was previously an editor at TechRepublic.

This story is part of Home Tips , CNET's collection of practical advice for getting the most out of your home, inside and out.

Hurricane Fiona made landfall in Puerto Rico over the weekend, leaving most of the island without power amid heavy rains and flooding. If you've been impacted by the storm, you may be wondering how to save the food in your refrigerator -- especially if the power stays out for several days, as experts are forecasting. And if you haven't, it's a good idea to prepare for the possibility of a power outage  at your home now, as extreme weather events like hurricanes and heat waves  are expected to continue affecting the US. 

Losing a fridge full of food is costly, inconvenient and potentially dangerous if you're unable to get out to a store in the middle of a storm. But there are ways to get ready ahead of time so that you can save all or most of your perishables. Here's what to do. 

For more disaster preparedness tips, check out our guide on how to prep for hurricanes, wildfires, storms and other natural disasters , and 11 things to do to prepare for a blackout .

Read more: Best Refrigerator for 2022

Before you face a power outage, it's best to take a few steps to prepare in case you need to save your food. The recommendation from the US Centers for Disease Control and Prevention is to have the following items on hand: 

Read more: Best Coolers for 2022

When an outage hits, keep your refrigerator and freezer doors closed -- don't open them up unless you absolutely need to, and even then, try to do so quickly so as not to let the cold air out. If the doors stay closed, your food can stay safe for up to four hours in a refrigerator, 48 hours in a full freezer and 24 hours in a half-full freezer, according to the CDC. 

Once you've passed the four-hour mark (or if you see the temperature inside the fridge has risen to over 40 degrees F) and the power is still out, it's time to start moving food out of the fridge. If perishable food has been left in the fridge after that point, you'll have to throw it all out. 

The exception here would be if you have dry ice. You can put the dry ice on the top shelf of your freezer and the bottom shelf of your refrigerator, and it will keep your perishables cold. You need about 3 pounds of dry ice per cubic foot of freezer space, which should keep food cold for at least two days. Just make sure you're aware of how to safely handle dry ice before using it. 

If the power is out for more than four hours, you'll likely want to move your perishable food to a cooler. 

First, you're going to make two piles: Food that absolutely must be kept cold, and food that is safe to leave on the counter until the power is back on. 

The following foods can be safely kept out of the fridge: 

The following foods must be kept at 40 degrees F or lower to prevent bacteria growth and spoilage: 

Once you've got your pile of perishable food, it's time to pull out your cooler and ice packs. Put a layer of frozen foods at the bottom. Then put a layer of foods from the fridge on top of that layer. Top it off with another layer of frozen foods. If you don't have any ice or ice packs, go to the store and buy some if it's safe to do so. 

Layer ice or ice packs around the food in the cooler -- don't just throw it all on top or bottom. Distributing the ice will keep the food at a more consistent temperature. Move your fridge thermometer inside the cooler to keep an eye on the temperature.

If you don't have a cooler, you can use your freezer instead -- it's insulated and will keep your food cold as long as you leave the door shut and keep a fresh supply of ice in it. To prevent melting ice from turning your freezer into a pond, put ice in bowls and place them around the food.

You should never taste food to see if it's gone bad -- when in doubt, throw it out, the CDC advises. Throw away any food with unusual odors, colors or textures right away. In terms of frozen foods, you can safely refreeze or cook thawed frozen food that is at 40 degrees F or below, or that still contains ice crystals.

For more tips on how to prepare for natural disasters, check out how to pack an emergency bag , and how to recover important documents after a natural disaster .