A recent Air Conditioning Contractors of America (ACCA) webinar led by Arkema's Sales and Technical Support Manager John Maiorana, and Senior Business Development Engineer Kris Crosby provided a detailed overview of the changes affecting refrigerant cylinders as the industry transitions to low-global warming potential (GWP) A2L refrigerants.
Maiorana and Crosby explained how cylinder standards, originally established in the 1970s by the U.S. Department of Transportation (DOT), have evolved to support the shift from chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) to hydrofluorocarbons (HFCs), and now to the new class of A2L refrigerants. These mildly flammable products, such as R-32 and R-454B, require updated cylinder specifications to ensure safety and regulatory compliance.
Maiorana noted that the familiar DOT 39 disposable cylinder remains the primary container for refrigerants. However, several updates distinguish the new A2L-ready versions from traditional models. The new cylinders include a resealable pressure relief valve instead of a rupture disc, which prevents complete venting of flammable gas in case of overpressure. They also feature a red band around the top to indicate mild flammability and a left-hand thread fitting to alert users that the contents differ from nonflammable refrigerants.
Crosby emphasized the importance of proper handling and storage, particularly ensuring that the pressure relief device is in contact with vapor, not liquid, when cylinders are transported or stored horizontally. These precautions reduce the risk of leaks and maintain pressure stability.
The presenters also addressed the phaseout and disposal requirements established under the American Innovation and Manufacturing (AIM) Act. Beginning in 2028, technicians will be required to recover any residual refrigerant—referred to as the “heel”—from disposable cylinders before recycling. Recovery can be done in the field or through certified reclaimers, with proper documentation required for compliance.
Maiorana and Crosby warned of noncompliant cylinders entering the U.S. market, often imported from overseas manufacturers that use pressure relief discs instead of valves. They advised contractors to verify that any A2L cylinders purchased include the required red band, flammable placard, and pressure relief valve, and to buy only from reputable distributors.
As the HVAC industry continues to adopt lower-GWP refrigerants, the experts stressed that understanding cylinder design, labeling, and disposal procedures is critical for both safety and compliance.
For HVACR contractors, understanding and following these new refrigerant cylinder standards isn’t just about meeting regulations—it’s about protecting technicians, customers, and the reputation of their businesses. As A2L refrigerants become the industry norm, contractors who prioritize safety compliance will reduce liability risks, prevent costly job-site incidents, and ensure systems perform efficiently under the latest environmental mandates. Staying informed and proactive about DOT and AIM Act requirements positions contractors as trusted, forward-thinking professionals ready to lead through the refrigerant transition.
This piece was created with the assistance of generative AI tools and was edited by our content team for clarity and accuracy.
