Environmental Management · HSSE Watch

Clean Energy Still Needs Leak Control: Hydrogen and SF6 Lessons

Published 28 October 2026

WMO bulletin and press release: 27 October 2026 · Worksite Safety Hub article: 28 October 2026

A low-carbon technology does not guarantee low climate impact if gases escape during manufacture, operation or maintenance. WMO’s latest greenhouse-gas bulletin reports record atmospheric concentrations and highlights two energy-transition integrity challenges: long-lived sulphur hexafluoride and hydrogen leakage.

What WMO reported on 27 October

The World Meteorological Organization release ↗ says globally averaged surface carbon-dioxide concentration reached 426.8 parts per million in 2025, or 153% of the 1750 pre-industrial baseline. Methane reached 1,948 parts per billion and nitrous oxide 339.1 parts per billion—also records.

These figures describe atmospheric concentration, not new annual emissions. WMO reports that average CO2 concentration rose by 2.8 ppm from 2024 to 2025. The report says the CO2 growth rate has tripled from an average 0.8 ppm per year in the 1960s to 2.4 ppm per year during 2011–2020.

WMO also reports a record 2025 increase in sulphur hexafluoride, or SF6. It describes SF6 as having an atmospheric lifetime exceeding 1,000 years and a 100-year global warming potential of about 24,300 times that of CO2. Atmospheric hydrogen concentration increased by 5.3% between 2010 and 2024. Hydrogen is not itself a greenhouse gas, but WMO says leakage can influence atmospheric chemistry and indirectly contribute to warming.

Why this matters to HSSE teams

SF6 is used mainly in parts of the electricity-transmission and distribution system because of its electrical properties. Hydrogen is expanding across production, transport, storage, industrial heat, steelmaking, shipping and long-duration energy storage. Both can deliver important operational benefits, but each needs controls that protect workers, assets and the climate.

The hazards are not interchangeable. Hydrogen is highly flammable and requires process-safety controls for loss of containment, ignition, ventilation and emergency response. SF6 equipment can involve high voltage, pressure and decomposition products as well as climate impact. A climate-leak programme must sit alongside—not replace—the applicable electrical, pressure and process-safety arrangements.

1. Build an equipment-level gas inventory

Identify where hydrogen and SF6 are received, produced, stored, transferred, contained or recovered. Record equipment type, location, capacity, gas quantity, pressure, service, commissioning date, owner and maintenance strategy. Include cylinders, mobile equipment, temporary connections, contractor-held stock and retired assets awaiting disposal.

Reconcile purchasing, charging, recovery and disposal records with physical inventory. A mass balance will not locate every small leak, but unexplained losses should trigger investigation. Keep units, gas grades and reporting boundaries consistent.

2. Design for leak prevention and maintainability

Specify leak-tight equipment, suitable materials, compatible seals, accessible test points and isolation arrangements. Minimise unnecessary joints and temporary hoses. Make future inspection, recovery and repair possible without creating unsafe work or routine venting.

For hydrogen systems, evaluate credible release locations, ventilation, dispersion, ignition control and hazardous-area requirements through competent process-safety design. For SF6 electrical assets, follow the manufacturer, network standards and authorised high-voltage procedures. Do not open or disturb equipment without the required isolation and competence.

3. Verify integrity during commissioning

Use approved inspection, pressure or tightness testing, instrument checks and documentation before introducing gas or energising equipment. Confirm that connections, valves, relief arrangements, detection and ventilation match the as-built system. Resolve construction debris, damaged seals and incorrect torque before startup.

Record the test method, conditions, acceptance criteria, instrument status, results and authorised release. A completed construction checklist is not proof of gas-tight integrity unless the required verification was actually performed and accepted.

4. Detect small losses before they become normal

Select fixed and portable detection for the gas, equipment and operating environment. Establish alarm response, calibration, bump-testing where applicable, inspection frequency and escalation criteria. Trend repeat defects and gas top-ups; do not treat them as routine consumption without investigation.

Use suitable techniques for the specific system, which may include concentration measurement, pressure or inventory trends, leak imaging or local testing. Have competent specialists interpret results. This article does not set detection thresholds or safe-entry criteria.

5. Control maintenance, recovery and contractor interfaces

Plan isolation, depressurisation, purging, recovery, transfer and return to service. Use equipment designed for the gas and pressure. Prevent cross-contamination and confirm cylinder identity, capacity, condition and connection compatibility.

Define who owns recovered gas and how it is reused, reclaimed or disposed of through authorised routes. Verify contractor competence and records rather than assuming a service certificate captures the full mass balance. Include emergency and abnormal work, not only planned maintenance.

6. Connect climate data with process and electrical safety

A hydrogen alarm can signal both a climate loss and an immediate fire or explosion hazard. The first response must protect people through the approved emergency arrangements. Similarly, work on SF6-containing switchgear must respect electrical boundaries, pressure hazards and potential decomposition products.

Integrate environmental, maintenance, engineering, operations and emergency information. Avoid separate dashboards that allow a climate trend to be reviewed without the related defect, or a safety repair to close without updating the gas inventory.

7. Plan alternatives and lifecycle decisions

When replacing or expanding equipment, evaluate lower-impact alternatives, reliability, safety case, training, spare parts and recovery arrangements across the full lifecycle. A lower global-warming-potential medium still needs safe containment and competent maintenance.

Prioritise replacement using condition, leak history, gas quantity, criticality and consequence—not age alone. Define how decommissioned gas and equipment will be recovered, verified and documented.

Leadership and toolbox questions

• Can we reconcile the gas purchased, charged, recovered, stored and disposed of?
• Which asset or connection has the highest credible leakage consequence?
• What evidence shows new equipment was leak-tested before startup?
• Which repeated top-up or alarm is being accepted as normal?
• Do detector calibration and response arrangements match the actual gas?
• Who owns the handover between electrical, process-safety and environmental teams?
• Can contractors demonstrate recovery quantities and authorised disposal?
• Which lifecycle decision would reduce both safety risk and climate impact?

Authoritative WMO video

WMO — Greenhouse gas levels once again reach record high. WMO embedded this directly relevant video with its 27 October 2026 release. It explains the global bulletin; it is not a plant-specific integrity procedure or evidence of leakage at any individual facility. Verify the video on WMO’s official release ↗ · Open the direct video ↗.