The car air-conditioning refrigerant rejected by Daimler due to safety concerns is safe and thoroughly tested, Honeywell said..
The company has stepped forward to defend its HFO-1234yf product after Daimler declared its decision not to comply with the EU directive, ordering car manufacturers to replace the previously prevailing climate warming coolant HFC-134a with Honewell’s HFO-1234yf, is justified based on the extreme flammability and potential toxicity of the latter.
“Industry safety experts agree that appropriate vehicle design vastly minimizes any refrigerant combustion risks. SAE has concluded that it is 300,000 times more likely that a vehicle would experience a fire for reasons unrelated to the refrigerant than due to its refrigerant – and that there is no significant risk caused by using HFO-1234yf,” Honeywell said.
Last year, while simulating a leak in the air conditioning line of a Mercedes B-Class tourer, Mercedes engineers discovered the new coolant was extremely flammable. They mixed the substance, of which Honeywell is the sole producer and patent owner, with A/C compressor oil and sprayed it across the car’s turbo-charged 1.6 litre engine. Not only did the substance catch fire as soon as it touched the hot surface, the burning process also released the extremely toxic hydrogen fluoride.
However, Honeywell dismissed the findings and, while Mercedes has been defending its decision not to use the coolant despite facing an EU sales ban, has reassured the substance was thoroughly tested.
"Many automakers have engineered their vehicles for HFO-1234yf because they saw it as the safest, most cost-effective and environmentally-friendly solution to comply with the EU Mobile Air Conditioning Directive,” Honeywell's statement said. “Their selection was backed by comprehensive testing conducted over a three-year period under the Cooperative Research Program (CRP) of SAE International, sponsored by 15 global automakers, including all leading German automakers.”
German transport authority KBA backs Daimler in the EU dispute and said the company should be given more time for further testing. "It can't be ruled out that the new coolant ... may endanger vehicle passengers and other road users," the German transport ministry said in a statement. “Available scientific findings do not yet allow for a final risk assessment, it added.
Honeywell further said the previously used coolant, the now banned HFC-134a, also has the ability to ignite and downplayed the risks related to the release of the toxic hydrofluoric acid. “SAE research demonstrated the quantities are well below thresholds that would affect human health and that, again, there is no significant risk caused by using HFO-1234yf.”
When the story first took off, Andreas Kornath, a chemistry professor at the University of Munich, described the fatal properties of the hydrofluoric substances on human organism: “Readily absorbed by the skin, hydrogen fluoride begins attacking the body once it enters the bloodstream by spreading death on a cellular level, a process known as necrosis,” he said, adding that high enough doses can cause the lungs to fill up with fluid, causing a drowning sensation, and to trigger cardiac arrest.