From luring mosquitoes away to keeping your perishables fresh, especially in power outages, it’s clear that dry ice has many uses. However, dry ice is also expensive.
Dry ice costs $1.00 to $3.00 per pound, which is more costly than ordinary ice, where you can buy a 5-pound bag of ice at the same amount.
When you’re dropping that kind of coin, it’s a good idea to get as much out of it as you can. Which is why I’m going to explain how long dry ice lasts in a cooler, plus show you a few easy ways to make it last longer.
How Long Does Dry Ice Last?
The rate that dry ice lasts depends on how long it takes to go through sublimation (the process of turning solid directly into a gas). With that, it’s then apparent that dry ice lasts longer when it’s heavier as it takes longer for all of a large brick of dry ice to sublimate than a smaller one. Here’s a summary of how long dry ice lasts depending on its weight:
|Weight of the Dry Ice||How Long It Lasts|
|5 to 7 pounds||18 to 24 hours|
|8 to 12 pounds||24 to 40 hours|
|13 to 20 pounds||40 to 60 hours|
Note that these weights are just for how long the dry ice lasts—not how long the contents of your cooler will stay cold. If you keep water bottles in the cooler with the dry ice, they’ll stay frozen for far longer than the 24 hours your dry ice is around.
Should I Put Dry Ice on the Top or Bottom of my Cooler?
Place your dry ice at the bottom of your cooler to make it last longer. This is because of the principle that hot air rises and cold air sinks, so if dry ice is more exposed to cold air, it will sublimate at a slower rate.
Leaving the dry ice at the bottom also reduced the risk that someone would accidentally touch it and get a dry-ice burn.
However, you may also opt to put dry ice on the top of your cooler. This is when you only have a limited amount of dry ice and want to freeze everything as fast as possible.
As cold air from the dry ice sinks, it will freeze everything at the bottom in the process, although just be aware that it will make the dry ice disappear more quickly.
6 Ways to Make Dry Ice Last Longer in a Cooler
Because dry ice is expensive, it’s best to be smart about using it so you can maximize its full use. Here are a few of my favorite ways to make dry ice last longer in a cooler:
1) Use the Right Cooler
Since dry ice typically has an extremely cold temperature of -109ºF (-78ºC), it’s best to know if your cooler can withstand this temperature.
For this purpose, soft coolers should be avoided because their inner linings are brittle and will break when you put dry ice inside them. In contrast, hard coolers are the best for dry ice use because the plastic used in them can handle dry ice.
Check out my favorite 20 qt hard coolers to see which brand is the best of the best.
2) Pre-Chill Your Cooler (and the Items You’ll Want to Place Inside)
Since coolers are designed to insulate temperatures, it’s intuitive that they can also trap warm temperatures. Storing dry ice in warm coolers can make your dry ice sublimate faster than storing it in pre-chilled coolers.
Similarly, items you’ll want to place inside must also be pre-chilled so it won’t take too much dry ice to make them cold or frozen.
3) Ensure That Gas Can Escape from Your Cooler
Dry ice can cause your cooler to explode if the gas that forms from its sublimation can’t escape from your cooler. Make sure to partially open the drainage plug or leave the lid off your cooler for a few moments so the gas can escape. After all, not all coolers are designed to be air-tight.
4) Use Insulating Materials
Wrapping the dry ice in a paper, cardboard, or a towel can help the dry ice get insulated and sublimate more slowly. Insulating the dry ice is also an excellent way to protect your food (and you!) from extremely cold temperatures.
5) Think About the Delivery and Pick-Up
Preserving dry ice can also depend on the timing to which you use it. Ask your dry ice to be delivered near the time you use it, so you’ll prevent prolonged sublimation. Make sure to avoid opening the cooler and packaging until you arrive at your destination, or you’re going to use the dry ice so you can maximize its longevity.
6) Buy A Larger Piece (or Use More)
For every 24 hours you’ll be using dry ice, add 5 pounds. You may opt to use a large block of dry ice or use more dry ice to make it last longer.
What is Dry Ice, and is it Safe to Use?
What is Dry Ice?
Dry ice is frozen carbon dioxide with a typical surface temperature of -109° F. It’s made by liquefying carbon dioxide, injecting it into a holding tank, and then compressing it into solid ice.
Dry ice can be made into pellet form or large blocks depending if they’re created in a pelletizer or a block press.
Unlike ordinary ice that melts, which changes from solid to liquid, dry ice sublimates, meaning it changes from solid to gas.
Uses of Dry Ice
- Food Industry – Dry ice pellets are added to food processes such as large-scale blending or grinding processes when producing hamburgers. This is done to prevent microbial growth during the procedure as extremely cold temperatures are detrimental to the growth of a lot of microorganisms. It can also be used in making frozen foods like ice cream.
- Deep Cleaning – Dry ice blasting machines may clean tough surfaces, especially those with adhesive materials like mold, glue, paint, oil, and grease.
- Medical Industry – Transport and storing organs to be transplanted can be done optimally using dry ice. Similarly, dry ice may also be used in dermatological procedures like mole removals and other procedures that can correct skin imperfections.
- Home Use – Dry ice has many applications at home. It can lure mosquitoes away, it can promote plant growth, can drive moths away from clothing, can help remove car dents, and can be used to remove bed bugs. The most obvious use of dry ice at home, however, is its ability to freeze stuff, meaning it can be used to maintain refrigeration upon power outages and to maintain cold temperatures for other purposes like camping, picnics, and vacation.
Safety of Dry Ice
Using dry ice is safe in areas with good ventilation but can cause asphyxiation when used in confined spaces because of its possible build-up.
Because carbon dioxide has a better affinity to the hemoglobin or oxygen-carrying protein of our blood than oxygen, our bodies can be deprived of oxygen when dry ice is used in confined spaces.
Early signs and symptoms of oxygen deprivation include:
- Difficulty breathing
- Bluish tint to the skin
Because of its extremely cold temperature, dry ice can also cause burns to the skin and frostbite when touched directly. As such, you should always observe the use of protective clothing when handling dry ice, such as wearing gloves when handling the material directly or using tongs to avoid direct contact with it.
Keep it Cool
How long a brick of dry ice can last depends on how long it takes to sublimate, so using larger bricks will help. You can also use different techniques to make dry ice last longer, like putting it on the bottom of your cooler, wrapping it in a towel, and adding regular ice.
Can dry ice last for three days?
Dry ice can last for three days given that you bought a larger brick of dry ice or you employed different techniques to make dry ice last longer, like putting it on the bottom of your cooler or wrapping it in a towel.
How do you make dry ice last longer in a cooler?
You can make dry ice last longer in a cooler by following these steps:
– Use a hard cooler
– Pre-chill the cooler and the contents
– Allow the gas to escape your cooler
– Wrap the dry ice in newspaper, a towel, or cardboard
– Buy a bigger piece of dry ice, and use regular ice as well
How can I make my cooler cold for three days?
You can use dry ice in conjunction with ordinary ice, so when all the dry ice is gone, your cooler may still be kept cold by the ordinary ice.