A German woman who feared the Earth would be sucked into oblivion in a black hole has failed in her court bid to stop the work of the world's most powerful atom smasher.

The higher administrative court in Muenster, western Germany, rejected her claims, ruling there was no evidence the work of the European Organisation for Nuclear Research (CERN) posed a danger to public safety.

"The plaintiff ... was worried that the experiments could produce so-called 'black holes' which could eventually lead to the destruction of all life on Earth," the court said.

However, the court noted that the CERN's own safety reports ruled out any danger to life. "Objectively, there is no evidence to doubt the correctness of these safety reports nor was any conclusive evidence presented," it ruled.

The woman had failed in a previous attempt to stop the work of CERN in Switzerland at the Federal Constitutional Court in Karlsruhe.

After a quest spanning nearly half a century, CERN scientists in July said they had found a sub-atomic particle that may be the Higgs boson or "God particle", believed to confer mass on matter.

CERN uses a giant underground laboratory where protons are smashed together at nearly the speed of light in the Large Hadron Collider, yielding sub-atomic debris that is then scrutinised for signs of the fleeting Higgs.

Other opponents have also sought to stop the experiments, fearing either a black hole whose super gravity would swallow the Earth or a theoretical particle called a strangelet that would in turn liquidise the planet.