Is it the end of the road for the automotive refrigerant rebels?

Well, after the better part of 18 months of claim and counter-claim between those who believe the HFO refrigerant R1234yf is inherently unsafe and those who don't, we have as close to a definitive decision on the subject as we are probably going to get.

The Joint Research Centre, the European Commission's officially-sanctioned scientific body, has filed its long-awaited report into the risks associated with the refrigerant. It found "no evidence of a serious risk in the use of this refrigerant in MAC [Mobile Air Conditioning] systems under normal and foreseeable conditions of use."

Officially classified as a scientific review of the available evidence, the JRC heard the case from those who have developed the product and those who doubted its safety claims. Part of the JRC review consisted of an examination of the evidence of Germany's KBA, which diplomatically had produced a conclusion from its own testing that could be interpreted as either positive or negative, depending on what position you held.

The JRC took it as positive, saying:

"The review reinforces the conclusions by the German market surveillance authorities the KBA, which stated that there is no sufficient supporting evidence of a serious risk that would entail the intervention of the authorities. The review of the 2013 KBA testing procedures was conducted as a confidence-building measure that the Commission had proposed to the Member States. The Joint Research Centre reviewed the testing procedures and the review was performed by the JRC in an open and transparent way, involving all stakeholders."

The JRC concluded that it "supports the evaluation of the KBA that there were no grounds for the authorities to take measures under the European general product safety legislation. Therefore, according to this legislation, the products tested have to be considered safe products."

This EC-endorsed thumbs-up for R1234yf should now mean that the automotive industry can proceed with installing the low-GWP refrigerant in its new cars.

It should also mean the EC ought to be able to pursue those who had refused to use the refrigerant for flouting the European MAC Directive, which requires the use of refrigerant with a GWP under 150. That group effectively consists of car-maker Daimler with backing from its fellow German car-maker Volkswagen.

Under European rules, the German government would be the subject of "infringement proceedings" for allowing its companies to disobey European regulations. At worst his could amount to a significant fine and further daily penalties until the Directive is complied with.

The assumption of the infringement rules is that this is passed onto the rebel firms, but this doesn't have to be the case, so it remains to be seen whether Daimler actually gets censured for its crime.

Interestingly, the EC has also signaled its willingness to include those countries that simply turned a blind eye to Daimler's rebellion and allowed the registration of Mercedes vehicles containing high-GWP refrigerant, in violation of the Directive. In that camp are the U.K., Belgium and Luxembourg.

Observers believe that the EC will seek to make an example of those who flouted or ignored the MAC Directive, given the law's importance as a flagship environmental policy. However, even though the Commission has accepted the conclusions of the JRC, Daimler could still seek the right of appeal to the European Court of Justice.

But for now, the cooling and automotive industries can go on with business as usual, and the manufacturers of the refrigerant have already signaled their intention to step up production of the HFO in volume. Honeywell said it continues to see strong adoption by global automakers and said the company is "investing in production capacity to ensure adequate supply worldwide."

Honeywell expects a significant plant in Louisiana to be at full production by 2016, and has also announced a joint venture with Japanese manufacturer Asahi Glass Corporation to expand production capacity in Asia by the middle of next year. DuPont meanwhile is increasing production in plants in China and Japan.

The news also means that development can go ahead on the various R1234yf-based blends for the stationary refrigeration industry, currently undergoing a variety of field trials. When the future of the HFO was in the hands of the JRC, there was some tension in the refrigeration sector that the blends touted by the likes of Honeywell and DuPont might not see the light of day.

The two main manufacturers of R1234yf made statements using language that was uncharacteristically direct for global corporations, leaving investors and observers in no doubt as to both the frustration and the relief that the JRC statement brought.

"The JRC's independent and unimpeachable report marks the final word on the safety of this environmentally-friendlier refrigerant, which automakers are using to comply with the EU Mobile Air Conditioning Directive," Honeywell said in a statement. "The commission's work leaves no doubt that R1234yf is safe for automotive applications."

DuPont reinforced the weight of evidence considered: "The JRC met with a range of stakeholders and conducted three public meetings to obtain input on the extensive safety testing that has been conducted on R1234yf for use as an automotive refrigerant. The KBA had concluded that its testing, based on the requirements of German product safety law, produced 'no adequate evidence' of a serious risk related to R1234yf."

Lest anyone might still be thinking of this as a European issue, DuPont also noted the significance for the U.S. industry.

"Automakers are using the refrigerant in cars sold in the European Union today, in compliance with the EU's MAC Directive [but] several automakers also are using the refrigerant for cars sold in the United States to take advantage of credits that encourage the use of products with reduced climate impact," DuPont stated. "We expect to see other automakers move to adopt the product."

The findings of the JRC report will be debated with member states at an EC technical committee April 1, so all eyes will be on whether Germany puts up any further resistance on behalf of Daimler.

And for anyone expecting this saga to end neatly, there is still another twist in the tale. The two manufacturers — Honeywell and DuPont — are expected to have to fight for R1234yf in the European courts in the coming months over an antitrust claim by fellow manufacturers.