A recent report by the North American Sustainable Refrigeration Council (NASRC) reinforces this sentiment, stating the number of U.S. stores using transcritical CO₂ refrigeration systems is projected to grow by 176% between 2024 and 2028, and the number employing CO₂ secondary systems is forecast to increase by 620%.

Additional proof of CO₂'s rising impact can be seen in the American supermarket sector. U.S. supermarket chain Kroger announced plans to install CO₂ (R744) transcritical units in all of its new stores starting in 2025. Kroger joins numerous other supermarkets, including ALDI, Whole Foods Market, Publix, Albertsons, Walmart, and others, that have already incorporated, or are intending to utilize, the natural refrigerant.

As CO₂ continues to increase its market share, this growth highlights a critical need: The industry must prepare its workforce for this transition. While many HVAC technicians are skilled in working with conventional refrigerants, CO₂ systems operate under much higher pressures, involve complex transcritical cycles, and require specialized tools and safety protocols. Thus, when it comes to HVACR contracting, what steps can the industry take to meet such a booming demand?

Training CO₂ Refrigerant Technicians

Chris Griffiths was immersed in the industry from a young age, informally serving as an apprentice for his dad’s contracting company at a young age.

After grade school, he further cut his teeth on CO₂ refrigeration through a training program in Bradford, U.K. While he initially served as a design applications engineer, emergency field needs thrust him on-site, working inside of convenience stores and cold rooms.

Today, he serves as the U.K. Technical Manager at Omega Solutions and an associate lecturer at the University of the West of England, carrying out a mixture of technical, business management, and educational consultancy services for a multitude of manufacturers, contractors, and end users.

“We have far too few technicians for the amount of CO₂ work that is out there,” said Griffiths. “The technology is developing at such a rapid pace, and trying to keep up with it from a technician’s standpoint is unbelievably difficult.”

As an educator and proponent of R-744, Griffiths is committed to introducing as many technicians as he can to the nuances of CO₂, helping to do his part as the demand continues to soar.

Even with the best teachers, Griffiths acknowledges the real work begins when class is over. And, as techs aim to put their newly acquired knowledge to the test, he encourages them to attach themselves to an experienced mentor and soak in as much wisdom as they can.

“Even if it’s just one day a month, do your best to shadow someone who is a specialist in the field,” he said. “Get them to sit down and explain every aspect of what they’re doing. Then, try it out yourself. If you physically perform an action, it’s very likely you won’t forget how to do it again.”

Regardless how busy everyone is nowadays, technicians truly interested in mastering their trades must make time to sharpen their swords, Griffiths said.

“You have to upskill whenever and wherever you can,” he said. “If you’re in a car, download and listen to an audiobook or podcast. Before you start your day, while eating breakfast, read a scientific paper on your. The more you can do, the better, no matter when it’s accomplished.”

Finally, never curb your curiosity, he said.

“Don’t be scared to ask questions,” Griffiths said. “If no one has the answers, then dive in and solve the problem yourself, but do it safely. Always keep an open mind and ask for clarification if you don’t fully understand a concept.”

Create a Comprehensive Plan

With busy schedules and agendas, many commercial HVACR contracting companies will be tasked to learn CO₂ refrigeration on the fly. With little to no time to send technicians to school, companies may consider training their own techs in-house or enrolling in virtual training.

Trevor Matthews, owner of RefrigerantMentor.com, who has two-plus decades of CO₂ refrigeration experience, compiled a list of steps contractors should consider to bridge the gap from traditional refrigerants to CO₂ refrigeration through his Train the Trainer webcast.

The first step is to identify core competencies and develop customized programs, said Matthews. This is accomplished by auditing the company’s knowledge and adjusting the curriculum accordingly.

“What do your technicians need?” asked Matthews. “You may have people who know very little about CO₂, and others who know a lot. Everyone’s going to have different needs, so, as trainers, we need to identify core competencies and develop programs that cater to new technicians and those with great deals of experience.”

Once a program has been created, instructors must emphasize the importance of clear communication.

“When it comes to CO₂, there’s a lot of new terms and approaches,” said Matthews. “Trainers should be able to articulate information effectively, encourage participant engagement, and respond to questions and concerns. Find points that resonate with the audience and encourage their ability to learn.”

Once the program is in place, it’s important to prioritize continuous learning and to adjust the curriculum when necessary.

“Implement a robust assessment process to evaluate the effectiveness of the training that’s being delivered,” he said. “This could include quizzes, practical assessments, and feedback from trainees.”

Never Stop Learning

As companies like Kroger and others adopt CO₂ systems at a brisk pace, the need for highly trained technicians has become increasingly critical. While the technology offers a promising solution for reducing global warming, it comes with its own challenges, particularly in terms of training and workforce preparedness.

As the industry continues to evolve, it’s essential for HVACR contractors to embrace comprehensive training programs that address both foundational knowledge and hands-on experience with CO₂ systems. By fostering a culture of structured, continuous learning and mentorship, companies can ensure their technicians are well-equipped to handle the unique demands of CO₂ refrigeration. Ultimately, the key to a successful transition lies in education, adaptability, and collaboration, as the industry works together to meet the growing demand for sustainable refrigeration solutions. Take the steps necessary today so that you don’t fall behind in the near future!