MEPs have clashed over plans for "stress tests", which are due to be carried out on nuclear facilities in the EU.
There were angry scenes during the Commission statement on 9 June 2011, which caused Energy Commissioner Gunther Oettinger to appeal for calm.
Mr Oettinger was outlining plans for the tests - ordered in the wake of Japan's Fukushima disaster - which are designed to see how Europe's nuclear facilities are able to withstand natural or man-made disasters.
The so-called stress tests will be performed on Europe's 143 working reactors and other atomic installations and will consider a range of factors, including seismic activity, flooding, and power loss at reactors.
But German Green MEP Rebecca Harms dismissed the plans as a "paper check" designed to "downplay the risks of nuclear power".
Ms Harms attacked the voluntary nature of the tests, saying it left the checks "largely in the hands of operators".
Her comments were dismissed by fellow German MEP Herbert Reul, who described Ms Harms' opinion as "naïve".
Mr Reul praised the commissioner, saying that although the plans were "not 100% what we wanted", they would not be improved by other MEPs "complaining and harking on about it".
British conservative Giles Chichester protested about the "internal German discussion", and asked MEPs to focus on "the European issue".
Germany has recently announced that all of its nuclear power plants will be phased out by 2022, becoming the biggest industrial power to give up nuclear energy.
However Germany's nuclear industry has argued that an early shutdown would be hugely damaging to the country's industrial base.
Meanwhile countries including the UK, France and Poland have all announced further development of nuclear energy.
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