An Education in Dry Ice

It’s DRY ICE for a reason – It Doesn’t “MELT”. 

A popular, but often misunderstood form of product storage, food preparation and transportation packaging is DRY ICE. Put simply, dry ice is a solid form of carbon dioxide (CO2). This happens when the CO2 gas is super-cooled to -109°F / -78.3°C. The now solid material can then be used in the form of a solid block or smaller pellets. 

The advantage of dry ice compared to normal ice produced by freezing H20 (water) is that the surface temperature (-109°F / -78°C) is significantly colder than normal ice (32°F / 0°C). However, unlike regular ice, dry ice doesn’t melt into a liquid as it warms up. Instead, it converts directly back into a gaseous form through a process known as sublimation. This is why it’s called “dry ice” – because it does not “melt.”

Who Uses Dry Ice?

Dry ice is used in a number of industries. In the food industry, the material is used to keep food from spoiling during shipping and transportation. The low temperature of dry ice reduces the growth of bacteria and slows decay. This makes food crisper, fresher and more appealing for longer periods of time. 

In the food processing world, hamburger producers have found that by adding dry ice pellets into production helps keep the temperature below the threshold needed for bacterial growth. This keeps the food safer and more appealing. 

In the entertainment industry, dry ice is often used by stage technicians to safely create a smoky effect without the need for an open flame. 

Most recently, dry ice was used for the transportation of vaccines developed to combat COVID-19. Analox engineers helped to develop safe and effective ways for vaccine shipments to be delivered in a timely way throughout the world.

Is Dry Ice Safe?

While dry ice provides many practical advantages over common ice, it also carries some risks. Unlike normal ice that turns to water as it melts, dry ice (CO2) returns to a gaseous state as it warms. This presents several risks to workers, transportation drivers and warehouse staff. 

While dry ice is safe for use in areas with good air circulation, an unsafe build-up can occur in smaller, enclosed spaces without good ventilation. This CO2 build-up affects the breathable air and can cause physical harm to humans. Symptoms of increased CO2 exposure include headache, confusion, disorientation, difficulty breathing and changes to skin color. If unchecked, asphyxiation (death) can occur. 

Because dry ice is being used by more people than ever before and some of these people are less familiar with the hazards, the Analox Group is encouraging proper CO2 safety monitoring that can reduce the risks of CO2 exposure. 

Protecting People From Melting Dry Ice

Analox offers several stationary and portable systems that have many touch points throughout the supply chain. This starts with the actual production of the CO2, in laboratories, then moves to logistics such as road and air cargo, distribution centers and warehouses, hospitals and vaccine facilities.

The popular CO2 Buddy is a self-contained portable carbon dioxide monitor that transportation workers use to protect themselves. One of the most compact units on the market, the CO2 Buddy can be clipped to a belt or clothing. The audible and visual alarms quickly alert users to the presence of CO2 and allow them to act before it is too late.

Analox also offers the Aspida portable monitor that not only protects users from CO2, but offers the added protection of monitoring inert gases like nitrogen that are frequently used in beverage and hospitality environments. 

How is Dry Ice Different Than Liquid Nitrogen?

There has been a lot of talk recently about the use of liquid nitrogen in cooking and food preparation. Both gases offer extreme solutions to keeping food items cold but there are differences. For instance, liquid nitrogen is much colder than dry ice. It is usually between -346°F /-210°C  and -320.44°F / 160.24°C-. This makes it more difficult to handle. It is also a liquid – not a solid. Liquid nitrogen is perfectly safe to use provided the proper precautions, including gas monitoring devices, are taken. The popular Analox Ax60+ is ideal for this, as it has the capability to monitor for multiple gasses simultaneously.

Being Safe Around Dry Ice

Anyone can take advantage of the many benefits of dry ice, but there are several safety techniques to keep in mind:

  • Wear heavy gloves before handling dry ice, as it can cause frostbite if it’s touched directly.
  • While it’s safe to use dry ice near food, it should never be ingested, as it can cause internal frostbite.
  • Only use dry ice in well-ventilated areas and don’t let the concentration of carbon dioxide in the air reach 1.5% or higher.

Dry Ice in production (the solid form of carbon dioxide)