Letters to EcoNews: Super Greenhouse Gases

Jordan Smith,  globalFACT

I read with interest the recent article written by Martha Walden about super greenhouse gas. I am the Executive Director of the Global Forum for Advanced Climate Technologies (globalFACT), a non-profit organization that promotes the important role of low-GWP (Global Warming Potential) HFCs, HFOs, and HFC/HFO blends.

 Specific to environmental protection and sustainability, low-GWP HFCs, HFOs, and blends help businesses achieve greater energy efficiency and reduced emissions. They can also be used in system retrofits, giving older hardware new life, rather than sending it to a landfill. We often say that there is much more to consider than GWP when evaluating refrigerant choice.

 We are glad to see that you are interested in the topic of refrigerants and their environmental impact.  With that said, we would like to clarify a few points in your article and request that you print a correction to the story.

 You write, “Some HFOs have an impressively low GWP, but they’re toxic…” Regarding toxicity, ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) has classified HFO-1234yf as a “class A” refrigerant, meaning “low toxicity.”

 Also, it is worth noting that HFOs can be blended with HFCs to reduce the overall GWP of a blend, enabling operators to meet environmental regulations while getting more life out of their existing equipment. We view this as a positive development for the industry.

 We hope that you will consider revising your story and will view globalFACT as a resource as you cover related topics in the future.


Martha Walden, Get on Board

Yes, the American Society of  Heating, Refrigerating and Air-Conditioning Engineers has classified 1234-yf, the particular HFO I wrote about in my column, as “lower toxicity,” a relative term. As I noted in my column, manufacturing 1234-yf entails the use of carbon tetrachloride, a known carcinogen that was being phased out until 1234-yf was introduced for automotive AC. Now with ramped up production, carbon tetrachloride has a rosy future. 

Also, 1234-yf degrades into trifluoroacetic acid [TFA], an undeniable toxin, but its association with 1234-yf currently falls within industry standards for what is considered safe for the environment. TFA is a type of PFAS (polyfluoroalkyl substances, also known as “forever chemicals”), the prevalence of which greatly concerns health practitioners and environmentalists alike. 

It’s not surprising that Mr. Smith’s organization, globalFACT, has different standards for acceptable toxicity than I do. It also has different values as he demonstrates with his contention that “there is much more to consider than GWP when evaluating refrigerant choice.” The global warming potential of a refrigerant is absolutely tops in my book. The low GWP of most HFOs is elevated when blended with HFCs, a common industry practice that Mr. Smith seems to regard as pure advantage. 

A little reminder: hydrofluoro-olefins [HFOs] are the latest fix from the chemical companies to deal with the extreme climate threat they made with their hydrofluorocarbons [HFCs], which they introduced to fix the ozone destruction they’d caused with their chlorofluorocarbons [CFCs] and hydrochlorofluorocarbons [HCFCs]. But I guess a high enough profit margin means never having to say you’re sorry.