Guest essay by Eric Worrall
Greens are celebrating that the US EPA has raised the quantity of cheap highly flammable climate friendly refrigerants which can be used in home appliances.
Trump’s EPA Backs a Climate Change Tweak Environmentalists Like
By Eric Roston
29 November 2017, 04:14 GMT+10
The Trump administration took a small step toward addressing climate change last week — it just didn’t put it quite in those words.
Without fanfare — or even a public announcement — the Environmental Protection Agency issued an arcane rule that allows refrigerator and air-conditioner manufacturers to increase the amount of three cooling chemicals they can use safely. In a twist, the change was welcomed by manufacturers that want to adapt and use chemicals that would cause less global warming.
Home refrigerator makers in particular now have the EPA’s authorization to phase out the use of HFCs, replacing them with a hydrocarbon called isobutane. Having the rule in hand frees manufacturers to go ahead with their phaseout plans without needing the Kigali Amendment ratified in the Senate, according to Messner.
The EPA rule raises what the agency considers the safe levels of hydrocarbon coolants. The rule is confined to refrigerators and air conditioners, because car AC systems might release inflammable chemicals during an accident.
“There are accidents,” said David Doniger, director of the Natural Resources Defense Council’s Climate and Clean Air Program. But “your home refrigerator is not going to run into another refrigerator at 30 miles per hour.”
The new EPA ruling is available here.
It is possible using more iso-Butane in a home fridges is not a big deal – the EPA ruling specifies a charge limit of 57g (2 ounces) of iso-Butane – not a lot of flammable gas. But the EPA is concerned enough about the flammability of iso-Butane to specify that it should only be used in new fridges.
From the EPA ruling;
EPA previously found isobutane, propane, and R-441A acceptable, subject to use conditions, in new household refrigerators and freezers. In the proposed and final rules, EPA provided information on the environmental and health properties of the three refrigerants and the various substitutes available for use in household refrigerators and freezers. Additionally, EPA’s risk screens for the three refrigerants are available in the docket for these rulemakings (EPA–HQ–OAR–2009–0286 and EPA–HQ–OAR–2013–0748).
Isobutane, propane, and R-441A have an ASHRAE classification of A3, indicating that they have low toxicity and high flammability. The flammability risks are of concern because household refrigerators and freezers have traditionally used refrigerants that are not flammable. In the presence of an ignition source (e.g., static electricity, a spark resulting from a closing door, or a cigarette), an explosion or a fire could occur if the concentration of isobutane, propane, and R-441A were to exceed the LFL of 18,000 ppm, 21,000 ppm, and 20,500 ppm, respectively.
To address flammability, EPA listed the refrigerants as acceptable, subject to use conditions, in new household refrigerators and freezers. The use conditions address safe use of flammable refrigerants and include incorporation by reference of Supplement SA to UL Standard 250, refrigerant charge size limits, and requirements for markings on equipment using the refrigerants to inform consumers and technicians of potential flammability hazards. Without appropriate use conditions, the flammability risk posed by the refrigerants could be higher than non-flammable refrigerants because individuals may not be aware that their actions could potentially cause a fire, and because the refrigerants could be used in existing equipment that has not been designed specifically to minimize flammability risks.
3. The charge size must not exceed 57g (2.01 ounces) in any refrigerator, freezer, or combination refrigerator and freezer in each circuit;
What makes me uncomfortable is the only reason I can think of for switching from non-toxic non-flammable CFCs to highly flammable iso-Butane is pressure from the green lobby, and maybe some cost savings. The rules have been changed just a little in a way which puts convenience and political correctness ahead of consumer safety.
There is another potential issue. If everyone follows the rules, 2oz of flammable gas may not be a big deal – though the stipulation that the iso-Butane only be used in new fridges is intriguing. But with cheaper iso-Butane on the market, how long will it be until corner cutting refrigeration technicians start charging old fridges with cheaper iso-Butane?