AUSTIN (KXAN) — In the situation of a power outage, it’s sometimes hard to tell if the food in your refrigerator and/or freezer is safe to eat or whether it needs to be thrown out. Below is a quick and dirty way to help determine if the food is still a go or needs to go. Introducing the Quarter Test.

The setup

First, place a cup of water in your freezer and let it sit. Once frozen, place a quarter on top of the ice. Make sure the cup is full of water that has frozen into ice, and not a cup of already crushed ice.

STEP 1: Place a cup of water in your freezer and let it freeze. Add a quarter to the top.
STEP 1: Place a cup of water in your freezer and let it freeze. Add a quarter to the top.

The situation

In the event of a power outage, keep your fridge and freezer closed as this will help keep the cold air locked in. Once the power returns, pull the cup out of the freezer.

It’s also a good idea to check the cup if coming back from a vacation or extended period away from home, in case there was an outage while away.

STEP 2: Pull cup out of the freezer once power returns.
STEP 2: Pull cup out of the freezer once power returns.

The test

Here’s where we find out if the outage was long enough to spoil your food.

If the quarter is still on top of the ice, you’re good! This means the outage was not long enough to thaw the ice in your cup, and therefore, not long enough to thaw the food in your freezer/fridge to the point of spoiling.

Scenario 1: If the quarter remains on top of the ice, the food is still good.
Scenario 1: If the quarter remains on top of the ice, the food is still good.

If the quarter is on the bottom of the cup, there’s trouble! This tells you the power outage was long enough for the ice to completely melt, causing the quarter to sink. In this situation, you would want to throw out all food in the refrigerator and freezer as it, too, likely thawed completely.

The freezer/fridge will likely automatically kick on once the power returns, so don’t be surprised to see the quarter underneath a frozen block of ice in the cup

Scenario 2: The quarter is on the bottom of the cup, so the food is no longer good.
Scenario 2: The quarter is on the bottom of the cup, so the food is no longer good.

If the quarter is somewhere in the middle of the cup, things get a bit hairy. The freezer food may be salvageable, but the food in the refrigerator may have perished. Further investigation is needed to evaluate freshness.

Do NOT use the “taste test” to determine whether the food is still okay to eat. It is better to use the “sniff test” or “visual inspection” for analysis, or if unsure, throw it out anyway.

Scenario 3: The quarter is in the middle of the cup, and further investigation is needed.
Scenario 3: The quarter is in the middle of the cup, and further investigation is needed.

By the numbers

The Centers for Disease Control and Prevention provides general guidelines as to the acceptable length of time without power before food spoils.

Guidelines from the CDC as to how long food can last in your fridge/freezer during a power outage
Guidelines from the CDC as to how long food can last in your fridge/freezer during a power outage

Other encouraged practices include avoiding opening the fridge/freezer doors during an outage as this helps the food stay cold longer, using a cooler with ice and/or freezer packs to store food or putting the food outside (out of the sun) if temperatures are below freezing.

Read more about CDC recommendations here.