Greenpeace Germany letter to OEMs: Toxicity of HFO too serious

By team, Jun 05, 2009, 11:56 4 minute reading

In a letter sent to German OEMs on 27 May, Greenpeace Germany is attacking the global car industry for deliberately or recklessly downplaying the formation of highly toxic hydrogen fluoride from HFO-1234yf by several magnitudes. A review of a SAE scientific paper supported by global OEMs revealed that at the correct rate of HF concentration “all passengers would die with close to certainty”.

“It is unknown to us if this is a factual error or if there are manipulative intentions behind this misinformation. Fact is, however, that the (correct) rate of HF concentration from the refrigerant 1234yf in a passenger compartment will not be around 150 ppm (depending on the vehicle) but will be a multitude of that. At these concentrations all passengers will die with close to certainty,” the Greenpeace letter, sent to the boards of all car manufacturers united in the VDA on 27 May, reads.

“As a result, the claim that 1234yf will be an alternative is not only wrong but also life threatening; the legal consequences not calculable,” the letter continues before calling on all carmakers to point out this dangerous misinformation in the automotive industry and correct the calculation.

Greenpeace refers to a peer-reviewed SAE Paper presented by Roberto Monforte, Fiat, at the SAE World Congress in Detroit on 21 April. The paper, obtained by, states that if 0.55 kg of HFO-1234yf are completely released in an accident and exposed to a flame inside the passenger compartment of a Pontiac Grand Prix model the concentration of highly toxic hydrogen fluoride will not surpass 150 ppm (parts per million). HFO-1234yf would therefore not pose a higher risk to the passenger than the currently used refrigerant R134a.

A calculation strongly rejected by Greenpeace and external industry sources, who suggest that this figure might be understating the actual formation of HF by up to 1000 times. If 0.55 kg of 1234yf are burned, 0.39 kg of HF will develop. Calculated on a cabin volume of 3m3 (weight of air 3.6 kg), a concentration of 100,000 ppm would occur, or 10.7%. As opposed to 150 ppm, this 1000 times higher concentration would be enough to kill busloads of humans. Even with varying vehicle types, the HF rate inside the compartment could be hundreds of times higher than that assumed in the SAE paper.

New generation of HFCs “a catastrophic development”

The Greenpeace letter, however, does not only point to the life threatening consequences of HFO-1234yf in case of an accident, but also strongly attacks the argument that the chemical substance proposed as an alternative for Mobile Air Conditioning would be ecological preferable:

“The possible “landslide” of the new HFCs – against any technical, ecological and long term also economic sense – would mean more than only the choice of a refrigerant. It would also mean the introduction of a new generation of fluorochemicals across the board, far beyond the market for MAC, and for unforeseeable periods of time. The consequences of such a misguided development would be additional burdens on the climate and unforeseeable consequences we will probably see only in some years or decades,” the environmental group predicts a “catastrophic development”.

Variety of decomposition products with unknown consequences

While the Global Warming Potential (GWP) of HFO-1234yf would be low enough to comply with an EU Directive prescribing the use of refrigerants with a GWP below 150 in all new cars sold in the EU as from 2011 on, the continued use of yet another generation of HFCs would be “intolerable”, the Greenpeace letter states. Given the past of F-gases, another decision for an HFC as a “solution” would only prove that the car industry “has not learned anything from four consecutive marketing campaigns by the chemical industry, the catastrophic consequences and the tedious process to ban CFCs, HCFCs and HFCs.”

In addition, the number of decomposition products from HFO, among them the herbicide TFA, could be largely underestimated. Tests commissioned by Greenpeace already in 2001 hinted at a multitude of decomposition products with partly high reactivity. That apparently even lubricants (PAG) break down to HF in contact with HFO in a MAC system, is a clear hint at the low stability and therefore high reactivity of this substance, the environmental group concludes.

Why not CO2?

After also attacking the claimed energy efficiency of 1234yf calculated in LCCP tests with “arbitrary and falsifying parameters”, Greenpeace concludes:

“Following all these reasons, we would ask you and urge you to abstain from a refrigerant that is toxic, non-efficient and in the real world climate-damaging; a refrigerant that has the potential to lead to deadly consequences when highly toxic decomposition products form during an accident, and one that will also abet the introduction of new fluorochemicals with unknown consequences. In that sense we call upon you to support the VDA in its two “pro CO2” commitments and against new chemicals, and once and for all clearly decide for natural refrigerants. Urge the manufacturers united in ACEA to follow your choice. Anything else is, given the past of F-gases and also the already know impacts from new HFCs, not to be excused and from our perspective not acceptable.”


By team (@r744)

Jun 05, 2009, 11:56

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