The Petroleum and Natural Gas Regulatory Board (PNGRB) has proposed allowing hydrogen blending of up to 5 per cent in domestic piped natural gas (D-PNG) supplies. Under the draft guidelines, commercial supply of hydrogen-blended natural gas (HNG) would not exceed the specified limit and would remain subject to existing city gas distribution (CGD) obligations. The proposed framework preserves requirements covering safety, pipeline and equipment integrity, gas quality, metering, billing, service standards, emergency response and complaint handling. The PNGRB may reduce the permitted concentration, introduce additional controls, suspend HNG supplies or require a return to natural gas if evidence, incidents, complaints, billing errors or uncertainty raise concerns about safety or compliance. Consumers, local authorities and emergency services would have to receive advance information about hydrogen concentration, billing arrangements, appliance guidance, emergency procedures and the rollout schedule. The guidelines would cover the chain from the hydrogen receipt and interface point through the blending facility and downstream commercial deployment area to domestic installations. Hydrogen production, transportation, compression and storage before the interface point, including upstream mobile cascade systems, would fall outside the framework and remain subject to applicable laws and approvals from the relevant authorities. The proposal excludes blending in compressed natural gas (CNG), automotive applications, transmission pipelines, pure hydrogen supply, refuelling, deblending and non-domestic PNG. The draft also sets requirements for gas quality, hydrogen concentration, mixture homogeneity, interchangeability and odourisation. It provides for emergency isolation, suspension of supplies and restoration of natural gas service. The initiative supports the government’s effort to promote cleaner fuels and reduce dependence on imported crude oil and natural gas, while recognising the heightened fire and explosion risks associated with hydrogen’s flammability.