Bangkok, Thailand (July 11, 2025) – The 47th meeting of the Open-ended Working Group (OEWG 47) of the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer successfully concluded its week-long session, laying crucial groundwork for the upcoming 37th Meeting of the Parties (MOP 37) in November 2025. Delegates grappled with a range of complex scientific and technical issues, demonstrating the Protocol’s continued commitment to addressing threats to the ozone layer and mitigating climate change, even as new challenges emerge, particularly those related to the pervasive issue of fluorinated gases that are also PFAS.

The Montreal Protocol, a landmark environmental agreement, has for nearly 40 years effectively phased out ozone-depleting substances (ODS) such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). With the 2016 Kigali Amendment, its mandate expanded to include a phase-down schedule for hydrofluorocarbons (HFCs), powerful greenhouse gases introduced as ODS replacements. OEWG 47 underscored the ongoing efforts required to ensure the Protocol’s continued success, now with the added imperative of navigating the risks posed by PFAS.

A significant portion of the discussions at OEWG 47 relied on the insights provided by the Protocol’s Technology and Economic Assessment Panel (TEAP). The TEAP’s 2025 Progress Report informed delegates on critical topics including the replacement of high-global-warming potential (GWP) substances in various sectors like foams, fire suppressants, metered-dose inhalers (MDIs), and refrigeration, air conditioning, and heat pumps. The report also shed light on the remaining uses of methyl bromide for quarantine and pre-shipment (QPS) applications, the use of HCFCs as feedstocks, and the potential impact of policies restricting per- and polyfluoroalkyl substances (PFAS) on the transition away from ODS and HFCs. The TEAP highlighted that broad bans on PFAS could narrow the availability of alternatives for Montreal Protocol-controlled substances and complicate transitions from ODS and HFCs, creating uncertainty and delaying investments in truly sustainable alternatives.

One of the key items on the agenda was the Terms of Reference (ToR) for the study on the 2027-2029 replenishment of the Multilateral Fund (MLF). This fund is crucial for assisting developing countries (Article 5 parties) in meeting their Protocol obligations. Discussions highlighted the urgent need for increased spending on Kigali Amendment implementation and robust support for transitions to energy-efficient technologies. While Canada introduced a new proposal for the ToR, several parties, including Kuwait, China, India, Lebanon, Saudi Arabia, and Argentina, preferred using the previous ToR decision as a starting point. A contact group was established to reconcile these viewpoints, ultimately agreeing to forward a bracketed proposal to MOP 37 for further consideration.

We urge MOP 37 to ensure the ToR explicitly encourages the adoption of natural refrigerants and avoids perpetuating reliance on PFAS-containing alternatives and break the cycle of regretful substitutions.

Life-cycle Refrigerant Management (LRM) also featured prominently, with Nigeria calling for support for the reclamation and destruction of refrigerants in Article 5 countries. Cuba introduced a proposal for studies and strategies to address the accumulation of end-of-life refrigerant gases in Article 5 countries, which gained broad support. The TEAP confirmed the feasibility of preparing a report on used and unwanted refrigerants, and delegates agreed to submit a revised proposal on this matter to MOP 37. For the Coalition, effective LRM must prioritize the responsible disposal of harmful substances and, critically, prevent the continued proliferation of PFAS in the refrigerant lifecycle, as well as phasing out the reliance on PFAS refrigerants in all applications as many alternatives are available in the market.

A significant debate arose concerning halon 1301 and other controlled substances used for fire suppression, particularly in the civil aviation sector. The International Civil Aviation Organization (ICAO) currently mandates that halon 1301 cannot be used in cargo compartments of new aircraft designs after 2024. However, the global civil aviation industry intends to seek an extension to this date due to concerns about potential PFAS regulations applying to alternative fire suppressants like 2-BTP. This issue highlighted the complex interplay between the Montreal Protocol’s goals and emerging concerns around PFAS.

Norway and Switzerland shared concerns about the EEAP’s risk assessment of TFA, referring to newer studies and the precautionary principle regarding the approach to PFAS. This debate strongly underscores our coalition’s message: simply replacing one harmful chemical with another, even if it addresses ozone depletion, is not a sustainable solution.

We must break the cycle of regrettable substitutions.

The increasing emissions from feedstock uses of controlled substances also drew concern. Despite being exempt under the Protocol, these emissions are higher than previously assumed, potentially delaying ozone layer recovery. The EU and Switzerland proposed establishing a contact group to address this, and a proposal on feedstock uses was forwarded to MOP 37. This is another area where a robust commitment to PFAS-free alternatives is essential to prevent unintended consequences.

Enhancing regional atmospheric monitoring of controlled substances was another key discussion point. Updates from the Vienna Convention General Trust Fund (GTF) Advisory Committee and the Secretariat highlighted progress in evaluating suitable monitoring sites, with lessons learned from a pilot project on Bhola Island in Bangladesh. However, concerns were raised about securing adequate funding and expertise to complete the global monitoring network. Accurate monitoring is vital not only for ODS and HFCs but also for tracking the broader environmental burden of PFAS, including those found in HFOs.

Finally, national and regional initiatives to support the implementation of the Kigali Amendment were discussed. Rwanda introduced a proposal for a one-day workshop before MOP 38 in 2026 to share information on regional centers of excellence and explore interlinkages with Kigali Amendment implementation. The proposal also requested a funding window under the MLF for non-manufacturing activities to support these centers. While many supported the initiative, concerns were raised regarding funding and the format of the proposed workshop. The proposal was ultimately forwarded to MOP 37.

Our coalition, the Coalition for PFAS-free Cooling and Heating, actively participated in a side event with ATMOsphere and the EIA on July 10. We highlighted the critical issues surrounding PFAS in HFOs and strongly advocated for the urgent opportunity to leapfrog directly to natural refrigerants. This transition is not just a preferable option but a necessary step to truly fulfil the obligations of the Kigali Amendment and avoid the next generation of environmental contamination.

OEWG 47 showcased the Montreal Protocol’s ability to adapt to evolving scientific and technical landscapes. However, the growing concerns around PFAS, particularly as “alternatives” to controlled substances, introduced a new layer of complexity and shared the need to raise awareness of the true environmental and human impact of PFAS refrigerants and the fact that they affect the whole world.

The collegial atmosphere generally prevailed, reflecting the Protocol’s tradition of focusing on science and technology over politics.

The outcomes of OEWG 47 will now serve as the foundation for critical policy decisions at MOP 37 in Nairobi, Kenya, later this year, where we hope to see a clear commitment to genuinely sustainable, PFAS-free solutions across all sectors.

The video recordings of the plenary sessions can be found here:

All the documents prepared before, during and after the OEWG47 can be found here: https://ozone.unep.org/meetings/47th-meeting-open-ended-working-group-parties

The EIA report on HFOs can be found here: https://eia.org/report/persistent-problems/

ATMOsphere HFOs updated report can be found here: https://atmosphere.cool/hfo-tfa-report-2025/

Photo by Bernd 📷 Dittrich on Unsplash