Feature

Can Dry Ice Save Your Food During a Power Outage?

By Nora Callahan · August 4, 2026 · 15 min read

The short answer: only consider dry ice for an unpowered appliance

Dry ice may provide short-term emergency cooling when a refrigerator has lost power or failed. It is not a routine addition to a functioning appliance, and it is never a substitute for temperature monitoring.

The strongest federal and university guidance addresses dry ice in freezers, not ordinary refrigerator compartments. The available evidence does not establish a tested, universal quantity or placement method for dry ice in a household refrigerator. Appliance size, insulation, food load, shelves, liners, sensors, controls and ventilation conditions vary too much for one method to fit every model.

Use this four-scenario summary:

Situation	Best initial response
Refrigerator is running normally	Leave it on its normal controls. Do not add dry ice unless the manufacturer gives clear, model-specific permission.
Refrigerator has lost power	Keep the door closed initially. If the outage will be prolonged, prepare insulated alternate storage before considering dry ice.
Freezer has lost power	Keep it closed. Conditional dry-ice quantities and placement guidance are available for certain full freezers.
Food can be moved safely	Use insulated containers to move it to a working refrigerator, freezer or suitable cooler. This is often more practical when appliance compatibility or room ventilation is uncertain.

Commercial gas supplier Greco Gas warns that dry ice in a running refrigerator-freezer may make the thermostat turn the cooling system off, potentially shutting down the freezer section. It also warns against direct contact with plastic or glass shelving because those materials may crack or break. These are reasons to avoid dry ice in a powered appliance and protect vulnerable surfaces—not proof that dry ice will damage every refrigerator. Review Greco Gas’s appliance and handling precautions.

Before putting dry ice in a refrigerator, consult the appliance manual or manufacturer. An absent prohibition is not the same as confirmed compatibility. If compatibility cannot be established, use insulated alternate storage instead.

Before buying dry ice, use the outage clock

Your first response to a power failure usually should not be to open the refrigerator and install extra cooling. Note when the outage began and keep the doors closed.

A closed refrigerator generally keeps food cold for about four hours. University of Minnesota Extension gives a qualified range of four to six hours, depending on kitchen temperature. A full, unopened freezer generally maintains temperature for approximately 48 hours, compared with about 24 hours for a half-full freezer. These are planning estimates, not guarantees, and they depend on keeping the doors closed. Michigan State University Extension summarizes the closed-appliance time estimates.

Every unnecessary opening admits warmer room air. During an outage expected to last only an hour or two, repeatedly inspecting the food—or opening the refrigerator to add a cold source—can reduce the cold you are trying to preserve.

If a freezer is not full, group frozen packages together so they retain cold longer. This is a cold-retention measure, not a substitute for checking temperatures after the outage.

A practical timeline is:

When the power fails: Note the time and keep the refrigerator and freezer closed.
During the first few hours: Check credible utility restoration information rather than repeatedly checking the food.
As four hours approaches: Reassess the likely outage duration. Locate appliance and food thermometers, insulated containers, ordinary ice, block ice or another appropriate cold source.
If a prolonged outage is likely: Move food to a working appliance or suitable cooler, or add an appropriate cold source if this can be done safely and efficiently.
When power returns: Use elapsed time and measured temperatures to evaluate the food. The presence of remaining ice or dry ice does not prove that every item stayed safe.

For more detail, see OutageGuide’s guide to the refrigerator four-hour rule.

Dry ice hazards that must be controlled

Dry ice is frozen carbon dioxide. Instead of melting into liquid water under ordinary conditions, it sublimates directly into carbon-dioxide gas.

Carbon dioxide can accumulate, displace oxygen and create a risk of unconsciousness or asphyxiation, especially in enclosed, poorly ventilated or low areas. Direct skin contact can cause severe cold injury. Gas released inside an airtight container can also increase pressure until the container ruptures. Able Appliance Repair summarizes the sublimation, oxygen-displacement, cold-contact and pressure hazards.

Control those hazards as follows:

Maintain good room ventilation. Do not use dry ice where adequate ventilation cannot be maintained. No supplied guidance establishes a universal safe household room size or ventilation rate.
Never seal dry ice in an airtight vessel. Do not put it in a sealed jar, bottle, inner container or gas-tight cooler. Sublimation continues while the dry ice is enclosed.
Protect your hands. Use insulated gloves, tongs or another suitable insulating barrier. Never handle dry ice with bare hands.
Keep children away. They should not be able to reach the material or its storage area.
Avoid enclosed and low areas. Carbon dioxide can collect where air circulation is poor.
Know the exposure warning. Rapid breathing may indicate carbon-dioxide exposure. If exposure is suspected, leave the area and seek emergency assistance.

A refrigerator door or cooler lid can remain closed to retain cold, but the dry ice must not be sealed inside an airtight inner vessel. A cooler containing dry ice must allow gas to escape. “Keep the cold in” must never become “seal the gas in.”

Room ventilation remains necessary even if the refrigerator itself is not airtight. University of Minnesota Extension specifically warns that accumulated carbon dioxide can cause unconsciousness or asphyxiation when dry ice is used for outage cooling. See its ventilation and handling warning.

A cautious checklist for an unpowered refrigerator

This is a risk-reduction checklist, not a universally validated installation method. Authoritative refrigerator-specific quantity and placement instructions are limited.

Confirm that the refrigerator is unpowered. Do not introduce dry ice while the appliance is operating. If electrical service is intermittent, prevent an unexpected restart before proceeding.
Obtain model-specific manufacturer guidance. Check the manual or ask the manufacturer whether dry ice is permitted and which shelves, liners, sensors or compartments must be avoided. If compatibility cannot be confirmed, choose another cooling method.
Ventilate the surrounding room. Establish ventilation before bringing dry ice inside and maintain it while the material remains in use. Do not proceed if adequate ventilation is unavailable.
Restrict access. Keep children away from the setup and temporary storage area.
Put on insulated protection first. Use insulated gloves or tongs. Arrange the appliance and insulating materials before handling the dry ice so you do not have to hold it while deciding what to do.
Use a non-airtight insulating barrier. Cardboard or another suitable insulating layer can separate dry ice from food and appliance materials. The barrier reduces direct exposure to extreme cold; it is not a guarantee that the refrigerator is compatible.
Prevent direct contact with vulnerable materials. Follow the manufacturer’s instructions for any additional material restrictions.
Keep dry ice away from bare food. Separate produce and other freeze-sensitive foods from the coldest area. Items close to dry ice may freeze or lose quality. Commercial cooler guidance similarly recommends insulation and separation for delicate foods near dry ice. Ben’s Dry Ice describes that vendor-recommended separation method.
Use an appliance thermometer. The food-safety objective is to keep the refrigerator at 40°F or below. Remaining dry ice does not establish that every part of the compartment stayed within that range.
Minimize door openings. Organize the food, barrier and thermometer before closing the door. Make any necessary temperature check brief.
Never use an airtight inner container. Do not try to slow sublimation by sealing the dry ice in a jar, bottle or gas-tight container.

There is no responsible universal answer for the exact quantity, position or duration of dry ice in a refrigerator compartment. Performance depends on:

Appliance volume and design
Insulation and condition
Starting food temperature
Food load
Room temperature
Dry-ice form and placement
Frequency and duration of door openings

That uncertainty matters. A refrigerator is intended to keep food near refrigeration temperature, while dry ice is cold enough to freeze nearby items and stress some materials.

Freezer guidance is stronger—and its numbers are conditional

Federal and university sources provide more concrete dry-ice guidance for freezers. Even there, the quantities apply to freezers of specified sizes and fullness levels. They are not refrigerator-compartment instructions and must not be converted into a pounds-per-cubic-foot formula.

Source and stated conditions	Dry-ice planning quantity	Estimated result
FDA: fully stocked 18-cubic-foot freezer	50 pounds	Cold for about two days
Michigan State University Extension: full 10-cubic-foot freezer	25 pounds	May remain cold for two to four days
University of Minnesota Extension: full 20-cubic-foot freezer	50 pounds	May remain frozen for about four days

The FDA figure applies specifically to a fully stocked 18-cubic-foot freezer. Michigan State University Extension’s estimate applies to a full 10-cubic-foot freezer and is expressly qualified with “may.” Review MSU Extension’s stated freezer conditions.

University of Minnesota Extension advises covering frozen food with cardboard and putting the dry ice on top of that cardboard. It pairs that method with gloves, careful handling and good room ventilation.

Do not average, scale or interpolate these examples. If your freezer does not match one of the stated conditions, do not invent a quantity from the table. Seek instructions applicable to the actual freezer and follow the dry-ice supplier’s handling directions. The published figures are conditional planning examples, not guarantees.

Duration varies with:

Freezer size and fullness
Insulation and overall condition
Initial food temperature
Ambient temperature
Dry-ice form and placement
Door openings
Air leakage and appliance design

The normal freezer operating target is 0°F or below. That is different from the post-outage recovery rule for individual foods. A freezer may have warmed above its normal operating target while some food remains eligible to be refrozen or cooked because it still contains ice crystals or measures 40°F or below.

Use temperature and elapsed time to decide what food is safe

The normal monitoring targets are:

Refrigerator: 40°F or below
Freezer: 0°F or below

After an outage, use measured temperature and elapsed time to make food decisions. Do not base the decision on how much ordinary ice or dry ice remains.

The FDA advises discarding refrigerated perishable food that has been above 40°F for four hours or more. An outage lasting no more than about four hours generally leaves refrigerated food safe if the refrigerator remained closed. Frozen food that still contains ice crystals or measures 40°F or below may be refrozen or cooked, although refreezing can reduce quality. Never taste food to determine whether it is safe, and do not rely on normal smell or appearance. Apply the FDA’s outage food-safety rules.

A commercial repair source gives a stricter two-hour statement for food above 40°F, but the FDA’s four-hour outage rule is the stronger basis for household refrigerated-perishable decisions in this situation. That does not guarantee every item is safe for four hours under all conditions. If the refrigerator was already warm, the door was repeatedly opened or measured temperatures show that food exceeded the safe range earlier, use that evidence instead of assuming the entire closed-door window applies.

Follow this post-outage sequence:

Record the elapsed time. Include any period when the appliance may have failed before you discovered it.
Read the appliance thermometer. When needed, use a food thermometer to check representative items without leaving the door open unnecessarily.
Separate food by category. Distinguish refrigerated perishables from shelf-stable foods.
Apply the FDA threshold. Discard refrigerated perishables known to have been above 40°F for four hours or more.
Evaluate frozen food separately. Food that still has ice crystals or measures 40°F or below may be refrozen or cooked.
Expect possible quality loss. Food may satisfy the recovery rule yet have poorer texture after thawing and refreezing.
Discard uncertain perishables. Do not taste food as a safety test.

This guidance concerns ordinary household food. It does not establish dry-ice or outage-storage protocols for medicines, infant formula or medical products.

When block ice or a cooler is the better practical choice

For a short outage, leave the refrigerator closed. Opening it immediately to rearrange food or add a cold source may admit warm air before extra cooling is necessary.

For a prolonged outage, FDA guidance advises obtaining dry ice or block ice to help keep food cold. That does not mean either choice is universally safer or more effective. The practical choice depends on the equipment, ventilation and monitoring available.

University of Minnesota Extension recommends moving food in insulated containers to a working cooler or refrigerator when a long outage is anticipated. An insulated cooler with ordinary ice, block ice, frozen gel packs or another suitable cold source may be preferable when:

The refrigerator manufacturer has not confirmed dry-ice compatibility
Appliance shelves or liners may be vulnerable
Adequate room ventilation is unavailable
Only a limited amount of food needs protection
The cooler can be monitored more easily
Food can be moved without unnecessary delay

If dry ice is used in a cooler, distinguish vendor setup advice from public-health guidance. A dry-ice seller describes using wrapped blocks, an optional thin insulating layer and added separation for delicate foods. That setup is vendor guidance, not a government-tested food-safety method. Regardless of the arrangement, do not make a dry-ice cooler gas-tight, and maintain surrounding-room ventilation.

Do not treat a vendor estimate of dry-ice life as a guarantee. Block size, cooler insulation, ambient conditions, food load, arrangement and lid openings can all change the result.

Use this decision comparison:

Constraint	Usually favors
Outage expected to end within about four hours	Keep the refrigerator closed
Prolonged outage with access to a working appliance	Move food in insulated containers
Refrigerator compatibility cannot be confirmed	Use an insulated cooler
Room cannot be adequately ventilated	Use ordinary ice or another non-CO₂ cold source
Full freezer during a prolonged outage	Consult conditional freezer guidance without scaling its examples
No thermometer available	Obtain one; no cold source proves food safety by itself

Do not use dry ice if you cannot maintain ventilation, restrict access, handle it with insulation, protect vulnerable surfaces or monitor food temperature. Under those conditions, alternate cold storage is the more controllable choice.

A final outage action plan

Use this sequence from the moment the power fails:

Note the time. Record when power was lost or when the appliance failure was discovered.
Keep the doors closed. Do not repeatedly inspect the food.
Check restoration information. Use credible utility or local-authority updates to determine whether alternate storage is likely to be needed.
Verify temperatures. Use an appliance thermometer and, when necessary, a food thermometer.
Prepare alternate storage. If the outage will be prolonged, organize insulated containers, a suitable cooler, ordinary ice, block ice or access to a working appliance.
Evaluate dry ice only after the basics. Confirm that the appliance is unpowered, adequate room ventilation can be maintained, insulated handling protection is available and the manufacturer has provided clear model-specific permission or instructions. If compatibility cannot be confirmed, do not use it in the refrigerator.
Keep the scenarios separate. - Running refrigerator: Leave it on normal controls; do not add dry ice without express manufacturer permission. - Unpowered refrigerator: Keep it closed first. Do not borrow freezer quantities or assume a universal placement method. - Freezer: Treat published quantities only as conditional examples for the exact stated sizes and fullness levels. Do not scale or interpolate them for another freezer. - Cooler: Use a suitable cold source, monitor temperature and never make a dry-ice cooler airtight.
Stop if conditions become unsafe. Discontinue the setup if ventilation becomes inadequate, carbon-dioxide exposure is suspected, children cannot be kept away, dry ice contacts vulnerable materials or temperature cannot be monitored.
Make the food decision from evidence. Use measured temperature and elapsed time—not remaining dry ice, smell or appearance.

During a declared emergency, follow local-authority and utility-provider instructions. This article provides general preparedness information, not emergency-services advice, as explained in OutageGuide’s emergency notice.

For an unpowered refrigerator, the compact checklist is:

Temperature: Keep at 40°F or below
Door: Keep closed as much as possible
Power: Confirm the appliance is completely off
Compatibility: Require clear model-specific manufacturer guidance
Room: Maintain adequate ventilation
Dry ice: Never seal it airtight
Hands: Use insulated gloves or tools
Food and surfaces: Prevent direct contact

Dry ice is a conditional, short-term cooling tool—not a substitute for a thermometer. For a short outage, keep the refrigerator closed. For a prolonged outage, evaluate insulated alternate storage first. If dry ice is considered, restrict it to an unpowered appliance with confirmed manufacturer compatibility, maintain ventilation, prevent direct contact and pressure buildup, and follow handling instructions. Decide whether refrigerated perishables can be kept by applying the FDA’s 40°F and four-hour rule, not by estimating how long the dry ice should have lasted.

Frequently asked questions

Can I put dry ice in a refrigerator that is still running?

Generally, no. Leave a functioning refrigerator on its normal controls unless the manufacturer gives clear, model-specific permission. Greco Gas warns that dry ice’s extreme cold may make the thermostat in a running refrigerator-freezer turn the cooling system off. See the supplier’s warning.

How much dry ice do I need for a refrigerator?

There is no authoritative universal quantity for a household refrigerator compartment. Do not scale freezer recommendations by volume or rely on a promised cooling duration. If the manufacturer cannot provide model-specific permission and instructions, use a suitable cooler or other alternate cold storage.

Can carbon dioxide from dry ice build up when the refrigerator door is closed?

Yes. Dry ice continually releases carbon-dioxide gas. That gas can leak into the room or be released when the door opens, creating a hazard where ventilation is inadequate. Keep the room ventilated and never seal dry ice in an airtight inner container. If exposure is suspected, leave the area and seek emergency assistance.

Should dry ice touch food or refrigerator shelves?

No. Use a non-airtight insulating barrier to prevent direct contact with bare food and vulnerable appliance materials. Food close to dry ice may freeze or lose quality, while extreme cold may damage some glass or plastic surfaces. A barrier does not make an incompatible refrigerator safe.

When must refrigerated food be discarded after a power outage?

Discard refrigerated perishable food that has been above 40°F for four hours or more. An unopened refrigerator generally keeps food cold for about four hours, but actual time and measured temperature should govern whenever available. Do not taste food to test its safety or rely on normal smell or appearance. Follow the FDA’s food-discard guidance.