Dry Ice for a Power Outage

As we weather the storm in the south and it heads for the east coast, it is a good time to revisit how to keep food safe in the event of a power outage. Being prepared is important not only for comfort, but also in keeping the food already in the home safe for consumption.

Once the power goes out, if you leave the refrigerator and freezer doors shut they will remain cold for 24 – 48 hours depending on how full they are. However, the longer the power is out, the higher the temperature will rise raising the risk of food spoilage. At -109 degrees F, dry ice can replace the cooling power of a refrigerator or freezer. During a power outage, place dry ice on the top shelf of the freezer and the bottom shelf of the refrigerator. In a standard freezer, you will need 25-30 pounds of dry ice to keep food frozen for one day. If you have a larger freezer you can plan on needing around 3 pounds for each cubic foot of freezer space. Less dry ice will be needed for the refrigerator since the food will not have to be frozen.  For power outages that last more than a few days, the dry ice will need to be replenished due to sublimation (the dry ice turning from a solid to a gas).

Then, once the power returns it will be important to evaluate the safety of the food in the refrigerator or freezer. The following is a good rule of thumb by foodsafety.gov:

“Thawed or partially thawed food in the freezer may be safely refrozen if it still contains ice crystals or is at 40 degrees or below. Partial thawing and refreezing may affect the quality of some food, but the food will be safe to eat.”

For additional information, click here for the United States Department of Agriculture webpage on, “Keeping Food Safe During an Emergency.” Also, find the Continental Carbonic location nearest you by clicking here as our branches may be able to assist consumers in keeping food, pharmaceuticals and other perishable items fresh in the event of a power outage.