Rules to curb tremors from fracking are as strict as banning buses driving past houses or slamming wooden doors, experts claim

The rules governing fracking could safely be relaxed to permit stronger earthquakes caused by drilling for shale gas, a study suggests.

The rules are so tight at present that even tiny earthquakes, which cause no more vibration at the surface than a door being slammed or a bus passing a house, could result in a fracking operation being shut down, its authors say.

The scientists, from the University of Glasgow, recommend that earthquakes deep underground measuring up to 3.6 on the Richter scale should be tolerated, with a compensation scheme for any damage on the surface.

The government banned fracking temporarily in 2011 after Cuadrilla’s exploratory drilling near Blackpool caused two earthquakes, measuring 1.5 and 2.3 each. The ban was lifted 18 months later but