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HFCs in Fire Suppression Applications

A recent article that appeared in the October 25, 2011, issue of Asia Fire Protection Magazine, "Skipping to Second Generation of Fire Suppression Agents," by Kurt Werner and George Ip (3M), contains several examples of misinformation related to the use of HFCs in fire suppression applications.

Dr. Mark L. Robin of DuPont Chemicals & Fluoroproducts has prepared a response to this article, citing factual third-party information.

» Read the Original AFP Article
» Read Dr. Robin's Response, below

Response to AFP Article on HFCs

No other issue related to clean agents is perhaps more misunderstood and misrepresented in the marketplace than the issue of environmental impact. This confusion and misinformation includes a lack of understanding of (1) the meaning of GWP values, (2) the impact of HFCs used in fire suppression on climate change, and (3) regulations related to HFCs in fire suppression applications. Unfortunately, the above-referenced article adds to the misinformation already prevalent in the marketplace.

GWP Values. A clear explanation of what GWP values are can be found in Section A.1.6 of the recently published (2012) edition of NFPA 2001 Standard on Clean Agent Fire Extinguishing Systems, which demonstrates the fact that the GWP value considered by itself does not provide an indication of the impact of an agent on climate change: "It is important to understand that the impact of a gas on climate change is a function of both the GWP of the gas and the amount of gas emitted. For example, carbon dioxide (CO2) has one of the lowest GWP values of all GHGs (GWP=1), yet emissions of CO2 account for approximately 85% of the impact of all GHG emissions." The GWP value for a gas simply compares the impact on climate change of the emission of the gas to that of CO2, e.g., a GWP value of 100 indicates that the emission of 1 kg of the gas in question has the same impact on climate change as the emission of 100 kg of CO2.

Impact of HFCs in Fire Suppression Applications on Climate Change. The relative contribution or impact of any GHG gas to climate change is readily found from an examination of the number of "CO2 equivalents" associated with the amount of gas emitted. CO2 equivalents are calculated by multiplying the mass of agent emitted by its GWP value, and are typically expressed in terms of "Tg of CO2 equivalents," calculated by multiplying the mass of emissions (in Tg) by the GWP of the gas in question.

Factual information related to the impact on climate change of HFCs in fire suppression applications is available from several independent sources. Appendix A.1.6 of NFPA 2001 (2012 edition), for example, indicates that, based on US EPA data (US EPA, Inventory of U.S. GHG Emissions and Sinks: 1990-2007), "... the impact (in Tg of CO2 equivalents) of HFC emissions from fire suppression applications represents 100 x (0.7/7150.1) = 0.0098 percent of the total impact of all GHGs; that is, the impact of HFC emissions from fire protection applications represents less than 0.01 percent of the impact of all GHG emissions." Emissions data are also available for EU-15 countries, and as is the case for the US, indicate that the relative contribution of HFCs in fire suppression applications to climate change is miniscule (Annual European Union GHG Inventory 1990-2009 and Inventory Report 2011, 27 May 2011).

Regulation of HFCs in Fire Suppression Applications. With regard to the regulation of any chemical, no one can guarantee a lack of future regulations, and speculation on this point serves only to confuse the industry and drive end users to non-clean alternatives such as sprinklers. No one can guarantee that HFCs in fire suppression applications will never be phased out -- not without being able to divine the future. Can anyone guarantee that perfluoroketones will not be phased out in the future? Unlike other clean agents, perfluoroketones are characterized by high chemical reactivity (e.g., hydrolysis when crossing the lung-air interface, cf. NovecTM 1230 Fire Protection Fluid Safety Assessment, 3M). Even the inert gases have been challenged by acoustic damage, high cylinder pressures, and room over-pressurization. Regulations continuously evolve as new science, information, and issues develop in the marketplace and no product is immune to a changing regulatory future.

It is a fact, however, that with regard to regulations, HFCs in fire suppression applications are being treated differently than HFCs employed in other applications. Emissions of HFCs from fire suppression applications are dwarfed by HFC emissions from other applications such as refrigeration. Regulatory bodies understand this, and to date HFCs in fire suppression applications have been subject to different sets of regulations. A good example is the F-Gas regulation in Europe, which has adopted, supported and regulated good industry practices around system filling, handling, and servicing of fire systems.

It is important when encountered with an assertion of impending legislative or regulatory action related to HFCs in fire suppression applications to always request two items: (1) a copy of the legislation and (2) the location of the text which is specifically related to HFCs in fire suppression applications. This will avoid confusing specific targeted information with broader market relevance, or extrapolating an action in one target sector to another entirely different sector, such as fire suppression. The two following examples from the Article in question exemplify these risks. The devil, as always, is in the detail.

The AFP article indicates that "It has been reported in the National Academy of Sciences that if nothing changes, HFC emissions are likely to be equivalent to between 9 to 19 percent of global greenhouse gas emissions by 2050.” This statement refers to the article, "The Large Contribution of Projected HFC Emissions to Future Climate Forcing," Velders, et. al., Proc. Nat. Acad. Sciences, (106), 27, page 10949, co-authored by DuPont (copy available at www.harc.org/images/PNAS-2009-Velders-0902817106.pdf). The article specifically relates to HFCs used in refrigeration, air conditioning and insulating foam production whose emissions dwarf those of HFCs from fire suppression applications. The report further indicates on page 10950 that HFC-227ea was not even included in the analysis due to its small use and emissions. The article supports the case for the use of alternative technologies and emission reduction schemes for highly emissive HFC uses, but offers no analysis or comment on the use of HFCs with respect to fire suppression.

The AFP article also references a petition to the US EPA to delist acceptable SNAP substitutes: "In May 2010, the US EPA received a petition to selectively remove HFCs from the list of acceptable substitutes under the EPA's Significant New Alternatives Policy Program (SNAP). This move could have a large impact on the fire protection sector …" The US EPA received the petition from the National Resources Defense Council (NRDC) in May of 2010. The petition is a request to remove a single HFC, HFC-134a, from the list of acceptable substitutes for CFC-12 in motor vehicle air conditioning systems maintained under EPA's Significant New Alternatives Policy (SNAP) program, and to remove HFC-134a from such list in any other end-use category (e.g., aerosols, stationary refrigeration) where more benign alternatives are available. Specifically, this was not a petition to "selectively remove HFCs" from the SNAP list, but a petition to remove one, highly emissive compound from specific refrigeration applications, for which the user industry was already moving to adopt a viable alternative. Before addressing the original petition, the EPA required the petition to limit the scope to new mobile air conditioning applications in new passenger cars and light duty vehicles only, and is now just beginning a process to determine whether such a transition can occur. Stakeholder input is currently being assessed and there has to date been no decision as to whether or not such a transition will occur in this specific market sector and application. As such it is puzzling to see it asserted that this petition could in some fashion affect the fire suppression industry.

As a footnote, the LEED program specifies that fire suppression systems not contain ozone depleting substances (ODSs), specifically CFCs, HCFCs or Halons. HFCs, inert gases and FK-5-1-12 are NOT ozone depleting substances and hence LEED credits can be obtained for the use of any of these clean agent systems.

Readers interested in how to obtain copies of any of the cited documents, or of the NRDC petition, can contact Dr. Robin.