New Delhi, July 19 -- As India prepares to expand hydrogen-based mobility, the Centre is tightening the technical framework for testing the quality of hydrogen used in fuel-cell vehicles, two people said.

The Bureau of Indian Standards (BIS), under the ministry of consumer affairs, has notified an updated Indian Standard laying down laboratory methods to measure impurities in hydrogen supplied to Proton Exchange Membrane (PEM) fuel-cell vehicles.

The move comes as fuel quality faces growing public scrutiny, with questions being raised over the performance and impact of newer fuels and fuel blends, including E20 petrol.

While the standard is voluntary unless mandated by a regulator, it provides a common technical framework for laborator...