Senator Leyonhjelm last week won support from fellow senators to launch a wide-ranging inquiry into the spread of what he terms the "silliness" of government intervention into people's lives from compulsory bike helmets to outdoor alcohol consumption.

"If we don't wind back this nanny state, the next thing you know they'll be introducing rules saying that you'll need to have a fresh hanky and clean underpants," he said on Monday.

Senator Leyonhjelm, though, denied his role in the nanny state committee was at odds with his involvement on an inquiry into complaints by residents living near wind farms that low-frequency noise was making them ill despite the lack of conclusive evidence of a connection between the two.

"That's the exact opposite of a nanny state," he said. "The nanny state is all about the government protecting you against yourself. The liberal principle is all about the government having a role to protect innocent bystanders".

Senator Leyonhjelm's position, though, was queried by Simon Chapman, who appeared as a witness at Monday's Wind Farm Inquiry hearing in Sydney.

The senator "wants rigorous, costly regulation of a non-disease that has never killed anyone, while wanting to loosen regulation of tobacco, which kills 6 million a year, and is predicted to kill a billion this century," said Professor Chapman from the University of Sydney's medical school.

Professor Chapman told the committee  there had been no case studies into so-called "wind-turbine syndrome" published in "any reputable medical journal", nor had any accredited acoustics, medical or environmental association "given any credence to direct harmful effects of wind farms".

Senator Leyonhjelm, who did not query Professor Chapman's evidence during Monday's hearing, defended the inquiry.

"Thousands of people are claiming to be adversely affected by wind farms [and] contrary to what we've been told by some people, these complaints are not confined to English-speaking countries," he said. "Responsible politicians take these sorts of things seriously."

While wind farms are the subject of the inquiry, infrasound from "very large fans in coal mines and power stations" were also "a legitimate area for the committee to inquire", the NSW Liberal Democratic Party senator said.

The Abbott government gave the issue of noise added weight this month by agreeing to appoint a Wind Farm Commissioner to address public worries as part of its deal with the Senate to pass a 20 per cent reduction in the 2020 Renewable Energy Target.

Range of views

The Wind Farm Inquiry, chaired by fellow crossbench senator John Madigan, heard from a range of witnesses on Monday, including Sarah Laurie, of the anti-wind farm Waubra Foundation.

Ms Laurie, an unregistered doctor, said there had been a "systematic failure" by health bodies to investigate illness caused by infrasound emitted by wind farms.

She said she had "personally helped to prevent a number of suicides" but that others had taken their lives as a result of their exposure to turbines.

Ms Laurie said she could not understand why groups such as the Australian Medical Association had failed to take up the issue of wind-farm noise despite the private concerns of some of its members. "It reflects very poorly on the organisation," she said.

"I did write on a number of occasions to the AMA and I'm yet to receive any response from them," Ms Laurie said.

The association said it sticks by its position, dated March 18, 2014, that testing shows "that in rural residences both near to and far away from wind turbines, both indoor and outdoor infrasound levels are well below the perception threshold, and no greater than that experienced in other rural and urban environments".

The association's  position was backed by Peter Dolan, operations director of the Environment Protection Authority South Australia, who said its two-month study of the Waterloo Wind Farm had found residents complained of infrasound noise even when the nearby wind turbines were shut down.

Mr Dolan said the concerns could easily be expanded to other sources of noise such as vehicles. "Many millions of Australians are exposed to infrasound from road traffic," he said.