The UK has approved a tightly scoped extension for halon 1211 in certain aircraft, citing short‑term safety needs while the wider phase‑out continues. Signed by Parliamentary Under Secretary Emma Hardy on 4 December 2025, the Statutory Instrument is laid before Parliament on 8 December and takes effect on 30 December 2025. It lands weeks before the EU’s milestone requiring halon‑free portable extinguishers on aircraft by 31 December 2025, a deadline that continues to shape supply chains across Europe.

What changes on the ground is specific. For portable fire extinguishers protecting cabins and crew compartments, the end date is extended for named UK defence aircraft in two groups: some until 30 June 2027 and another set until 31 December 2040. A separate, shorter extension applies to listed Loganair aircraft until 31 December 2026. The legal basis used is Article 13(4) of the assimilated Ozone‑Depleting Substances Regulation, which can be triggered where no technically and economically feasible alternative is demonstrated.

The move sits within long‑standing ozone rules. UK guidance already restricts ODS use in new equipment and only permits recycled halons for critical uses under strict conditions. The government says these derogations are narrow and time‑limited, with consultation undertaken before the instrument was made.

Why halon 1211 matters is straightforward science. As bromochlorodifluoromethane, it carries bromine to the stratosphere where it destroys ozone very efficiently. The latest WMO/NOAA assessment reports an ozone‑depletion potential of about 7.1, an atmospheric lifetime of roughly 16 years and a 100‑year global warming potential near 1,990-signals that even small releases pack a punch.

Monitoring data show progress but not a free pass. NOAA’s Global Monitoring Laboratory records halon‑1211 in the atmosphere and has documented the long tail of these emissions as stocks are recovered and destroyed or recycled. Decades of controls have slowed growth and then nudged levels down, underscoring the value of sticking to phase‑out dates.

Aviation is now at a pivot point. EU Regulation (EU) 2024/590 and EASA guidance require halon‑free portable extinguishers by 31 December 2025 for EU‑registered operators, with a defined derogation process where safety and feasibility issues persist. That broader framework explains why the UK has carved out only narrow, time‑boxed extensions while signalling the destination remains the same.

Alternatives exist for many aircraft types, though drop‑in swaps are rarely simple. Certification programmes are expanding and supplemental type certificates are being issued to retrofit legacy fleets with approved non‑halon handhelds, an indication that supply and engineering pathways are maturing even as some models still face design and weight constraints.

For operators, the priority now is practical execution. Audit every aircraft location where portable extinguishers are required, secure halon‑free units with the right approvals, and book modification slots early to avoid year‑end bottlenecks. Coordinate with halon banks for responsible recovery and disposal, update maintenance and crew training materials, and re‑check weight and balance data after installations. Keep a close eye on new approvals: EASA and national authorities continue to publish guidance on compliance and on any case‑by‑case derogations.

Defence platforms often face longer certification cycles and mission‑specific constraints; the 2027 and 2040 dates reflect that reality without reopening the door to unrestricted halon use. In parallel, the EU’s updated ozone rules tighten controls across sectors and keep pressure on innovation, ensuring that exemptions remain exceptional, not routine.

The environmental payoff is tangible. UNEP’s Scientific Assessment Panel expects global ozone to recover to around 1980 levels by about 2040 if current policies hold. Staying on schedule-while managing safety in the cabin-keeps that recovery within reach. The UK’s measure is framed as a bridge, not a bypass: a short extension for named fleets while the industry completes the switch to halon‑free handhelds.