EFCTC contributes to ECHA Public Consultation on proposed restriction of PFASs in fire-fighting foams
The documentation for the proposed restriction of PFASs in fire-fighting foams covers a broad range of substances that have never been used in these foams and which do not have the technical properties to be used. The properties and environmental effects of HFCs, HFOs and HCFOs, which have not been used in these foams, are discussed in the documentation consisting of a REACH Annex XV report, annex, and appendix. It is possible that data contained in this fire-fighting foam restriction proposal may be used in the broad PFASs restriction proposal (available on the ECHA website ). Therefore, EFCTC has submitted a contribution to the ECHA Public Consultation to provide additional sources of information about the environmental effects of HFCs, HFOs and HCFOs and some clarifications regarding their global warming potential and degradation.
Some F-gases are used in very specific and limited cases for clean fire-extinguishing and suppression techniques (not foams), which are not in scope of this restriction proposal.
Degradation of HFOs, and HCFOs
Although the F-gases in scope of the proposed restriction, specifically the HFCs, HFOs and HCFOs, are a distinct subset of PFAS, not all of them form TFA on degradation. HFC-125 (pentafluoroethane) degrades completely to HF and CO2 in the atmosphere as only one reaction pathway is available [1].
EFCTC has identified three main issues discussed in the report and annexes and has provided further information.
- TFA yields from the degradation of most HFOs, and HCFOs. The EFCTC analysis Published evidence supports very low yields of TFA from most HFOs and HCFOs - Fluorocarbons concluded that 10% TFA yield in the documentation is a considerable overestimate for HFO-1234ze, HFO-1336mzz and HCFO-1233zd. EFCTC believes that its analysis would contribute to an improved understanding of degradation.
- The possible formation of HFC-23 (fluoroform, CHF3) from some HFOs. The documentation gives undue emphasis to the atmospheric degradation of HFO's as an unrecognised and secondary source of HFC-23. This has been disproved by a 2022 paper, which observed no formation of HFC-23 under any of the experimental conditions.
- Global warming potential of degradation products from HFOs and HCFOs. EFCTC provided authoritative data sources for the HFOs and HCFOs, demonstrating that formation in the atmosphere of degradation intermediates or final products with high GWP is not significant; more information is available here.
EFCTC is ready to further support the authorities in their decision-making exercise regarding fire-fighting foams.
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