NFPA Journal - May/June 2017 - 91

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RIPPLE EFFECT New requirements for refrigerants will also affect a variety of heating, ventilation, and air-conditioning applications.

effectively banning them for most large-scale applications.
For instance, UL 471, Commercial Refrigerators and Freezers,
limits the charge size for A3 refrigerants such as propane to
150 grams, or about half a cup of liquid. That is enough to run
a small beverage cooler at a supermarket checkout line, but
not nearly enough for the large glass-door refrigeration cases
in the dairy or frozen-food aisles.
Industries that rely on refrigeration are eager to see charge
limits for these more environmentally friendly yet flammable
refrigerants increased. Some are frustrated that, while environmental regulation is mandating change, safety regulation
is limiting their ability to take steps to comply. Some are forging ahead anyway as best they can.
In January 2016, U.S. retailer Target announced that it
would begin to transition to lower global warming potential
refrigerants in new and replacement stand-alone refrigeration
equipment in its stores. The company identified propane as
the ideal choice both because it meets future environmental
standards, and Target's internal testing has shown that propane is over 50 percent more efficient as a refrigerant than
HFCs, Paul Anderson, the director of engineering at Target,
said in an interview. The transition has started with small
propane self-contained refrigerant coolers with charge sizes
up to 150 grams, the maximum amount currently allowed by
the EPA.
"There is not a silver-bullet-solution refrigerant that exists
for retailers, but we need propane as one of the tools in our
toolbox," Anderson said. "We want to get there sooner rather
than later, because you can imagine the costs of switching refrigerants every few years. We need to get to an end

game that is best for our employees, customers, and the
environment."
Although there are now 600 Target stores with small
propane refrigerant coolers, there would be many more-
including some smaller stores using propane refrigerants
exclusively-if not for code restrictions on charge sizes for A2
and A3 refrigerants, Anderson said. For stores to use propane
refrigerants exclusively, A3 charge-size limits would need to be
increased to 1 kilogram to accommodate larger refrigeration
cases, he said. European
standards now allow
charge sizes up to 1.5
CONFERENCE
SESSION
kilograms for flammable
refrigerants in some
New HVAC
Refrigerants and
scenarios.
the Fire Challenges
Despite the chargeThey Present
limit restrictions,
Sunday, June 4,
8:30-9:30 a.m.
larger-scale use of
Bill Walter, UTC
propane refrigerants
Building & Industrial
Systems
is starting to be tested
Rusty Tharp, Goodman
in the U.S. Last year,
Manufacturing
a 49,000 square foot
Whole Foods in California received permission from the EPA and local authorities
to test market what's called a "cascade" refrigeration system
that uses a combination of propane and carbon dioxide. Seven
chiller units on the building's roof contain a total of about
265 pounds of propane, which never leaves the roof. Instead
it's used to chill and condense the CO2, which then travels
throughout the building below chilling the supermarket
N F PA . O R G / J O U R N A L * NFPA JOURNAL

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Table of Contents for the Digital Edition of NFPA Journal - May/June 2017