Dyson has accused rival vacuum cleaner manufacturers Siemens and Bosch of misleading consumers about the power consumption of their models.
In a development that echoes the recent Volkswagen emissions scandal, Dyson says its competitors’ vacuum cleaners claim to draw just 750W which is only true when there is no dust, as is the case in testing situations.
It claims the Siemens Q8.0 and Bosch GL80/In'Genius ProPerform models use a sensor that sends signals to the motor to increase its power as the machine sucks up dust. This equates to a rating as high as AAAA in test conditions that could drop to an E or F in real-world use.
Dyson said: "Consumers purchasing these machines on the basis of their widely advertised stated AAAA rating are being misled.
"Dyson has issued proceedings against Siemens in Germany and Belgium and Bosch in the Netherlands and France."
Sir James Dyson, owner of the company, said the power systems are implemented in order to cheat the EU energy label and made comparisons to Volkswagen’s attempts to conceal the emissions produced from its diesel vehicles from regulators.
"It seems that industry is rife with manufacturers engineering to find their way around tests, rather than engineering better, more efficient technology,” he said. “This behaviour is seriously misleading customers."
Bosch responded by 'strenuously rejecting' the allegations.
A statement from BSH Home Appliances, on behalf of Bosch and Siemens, said: "All Bosch and Siemens vacuum cleaners are measured in compliance with European energy regulations. Appliance performance at home is consistent with laboratory performance - and any suggestion to the contrary is grossly misleading.
"The purpose of energy labelling is to give consumers a clear and independently-validated indication of energy consumption and broader performance criteria. We have a long and proud tradition of stringent testing.”
This is not the first time that Dyson has publicly clashed with Bosch. In 2012 it accused its German rival of implanting a mole within a high-security research and development department in Wiltshire. The engineer was reportedly handing company secrets to Bosch for a two year period.