The phase-out of the last major ozone-depleting solvent, HCFC-225, finally has been completed. In addition, in many parts of the world, the regulatory pressure on older chlorinated solvents also has increased, so users of nPB, TCE, methylene chloride and other fluids also are migrating to newer, better and safer alternatives.
Mike Jones, MicroCare, New Britain, CT, USA
The good news,” reports David Ferguson, product manager at MicroCare Corp., “is that the industry is meeting the call to develop new cleaning alternatives. In the past two years, we have seen more new chemistries come out of the lab and onto the market than we saw in the entire decade before.” But none of the alternatives are a slam-dunk, according to Barbara Kanegsberg, president of BFK Solutions, a US consulting firm specializing in precision cleaning issues. “Anybody who does not have a cleaning strategy needs to be developing one urgently, and telling his boss to budget for it, right now.”
Life on this planet is protected from dangerous solar radiation by a thin layer of ozone in the upper atmosphere. This layer is constantly in turmoil, with ozone being created and destroyed in relative balance. In the 1970s, it was discovered that synthetic chemicals were depleting this protective barrier faster than nature could restore it. After just a few years of debate, more than 100 nations agreed to the Montreal Protocol1) that set the rules for globally eliminating ozone-depleting substances. The first chemicals banned were the refrigerants, aerosol propellants, blowing agents and precision cleaning solvents called Class I ozone-depleting substances. Now the less damaging Class II solvents have been phased out, and the last among these is HCFC-225.
Thirty-four different HCFCs fluids were developed as interim replacements for the widely popular CFC materials. HCFC-225 was the last of the precision cleaning solvents to be phased-out because it had the lowest projected impact on the ozone layer. This policy was both prudent and practical: HCFC-225 has an ozone-depleting impact approximately only 1/25 of the far more popular CFC-113 fluid. HCFC-225 also is a very good cleaner, nonflammable and fast-drying, VOC-exempt, with a relatively low global warming potential2). Since companies found the transition from CFCs to HCFCs to be relatively painless they made the change fairly quickly, which helped minimize the damage to the ozone layer.
Was the use of HCFCs ever a smart public policy? Many people disagreed with it; Greenpeace describes “the commercial and political influence of the chemical industry” as a major barrier to environmental improvements.3) But Howard Sidebottom and James Franklin in their definitive study wrote that “HCFCs have played an essential role, as interim replacement compounds, in ensuring the speedy elimination of CFCs.”4) So it is a case of the least bad answer, and the EPA (Environment Protection Agency) clearly agreed: one HCFC-225 product received the Best of the Best Stratospheric Ozone Protection Award from them in 1997.5) This pragmatic approach to protecting the environment is the proper path for future efforts, according to MicroCare Corporation’s COO Tom Tattersall. “The teamwork and collaboration behind the Montreal Protocol is the optimal role-model for government-industry co-ordination,” he said.
