The IIAR HC (Hydrocarbon) Standard has continued to move forward and was recently released for its first public review. The 45-day public review ran from July 7 through August 21. As of early August, the standard had received 92 comments.

“Having the standard out for public review is great progress. The committee has gotten it out in a good amount of time,” said Dave Malinauskas, president at CIMCO Refrigeration and IIAR’s board chairman.

“Having the standard out for public review is great progress. The committee has gotten it out in a good amount of time.”

Dave Malinauskas, president at CIMCO Refrigeration and IIAR’s board chairman

As part of the ANSI process, proposed standards have to be submitted to the public for comments, said Joseph Pillis, the IIAR HC subcommittee chair.

Tony Lundell, IIAR’s senior director of standards and development, is the IIAR Staff facilitator for the IIAR HC Standard in Development, said the standard is 424 pages and includes general design and specific design for designing refrigeration systems that utilize natural hydrocarbon refrigerants, which have very low global warming potential.

The hydrocarbon standard follows a similar framework as the IIAR CO2 standard and will serve as a complementary standard to ammonia and CO2. Plus, this standard is intended to parallel/harmonize the ASHRAE 15 standard with general design requirements, which are building code requirements used by fire marshals.

“This IIAR HC standard also includes specific design, installation, startup, as well as inspection, testing, maintenance, decommissioning, and general safety equipment,” Lundell said.

Pillis explained that the current draft of the standard covers the use of Propane, Butane, and Iso-butane in refrigeration applications, with the potential to add a few other hydrocarbons at a later date. “The standard has exceptions for listed systems and those systems for use in Chemical and Petrochemical applications. Listed systems are those built to UL standards, currently utilizing less than 150 grams of refrigerant per circuit,” he said. “This amount will be increased over time as the UL standards for HC systems are revised.”

For systems utilizing larger refrigerant quantities than covered by the UL standards (i.e., listed: equipment that has been tested and is identified as acceptable by an approved, nationally recognized testing laboratory) the refrigerant containing equipment shall be installed in a machinery room or outdoors, Pillis said. “A secondary refrigerant would generally be used to transfer heat from the source to the hydrocarbon equipment,” he said.

The natural hydrocarbon refrigerant, which remains in the machinery room, can be used as the primary refrigerant in a cascade system and/or for secondary systems that can chill and circulate a secondary fluid, such as a safe and different natural refrigerant (e.g., CO2), brine or glycol.

The task force had already completed a pre-public review with select individuals, which received hundreds of comments. The pre-public review was designed to capture what is presently known and/or already being done as good engineering practices and to help make the public review period result in requiring fewer comments which will be more manageable. Pillis said he expects to receive a considerable amount of feedback as part of the public review.

The petrochemical industry has a long history of using hydrocarbons, and they are increasingly being used in some refrigeration applications where other refrigerants are not allowed, are difficult to use, or are inefficient.

“Hydrocarbons have been used as refrigerants for well over 100 years and they are well-understood and very efficient refrigerants. They are naturally occurring substances having minimal impact on the environment as they have no ozone depletion potential and very low global warming potential,” Pillis said. “They are, however, highly flammable, and particular care must be taken in all aspects of their use to avoid the risk of fire.”

A hydrocarbon standard is becoming even more critical as the government, industry, and private entities address refrigerants, and the hope is that a standard will allow systems to safely expand in size and quantity of refrigerant to increase capacity while being energy efficient.

For IIAR, developing a hydrocarbon standard was a natural extension of the association’s mission to offer safe practice standards for other natural refrigerants as the use of low global-warming potential refrigerants grows.

After the public review, the committee works to address the received comments and develop responses for each quickly. Being a new standard, it is expected to have additional public reviews. The goal is to have the standard fully completed in 2024. The standard’s purpose has been presented to the EPA SNAP (Significant New Alternatives Policy) Team for their understanding and consideration to get approval.

Lundell said the consensus from the SNAP team is that hydrocarbons can be used in industrial process refrigeration systems, including being the primary refrigerant for Cascade Systems and for chilling secondary fluids.

Those interested in getting involved in the development of responses to public comments can contact IIAR and express interest in joining the committee.