Enterprise, trade and employment Minister Micheal Martin had promised a range of special measures to prevent the exploitation of the increasing number of domestic workers employed in private houses to cook, clean and look after children.

Among the measures, to be introduced once the new national pay deal is ratified by the unions next month, is an obligation on householders to keep employment records showing that their domestic workers are being paid the legal minimum wage and getting the right amount of leave.

But while the department's labour inspectors can already legally enter workplaces countrywide to check records and enforce worker-protection legislation, there is now considerable doubt over whether they are entitled to do the same in private houses.

"The exercise by inspectors of their powers, insofar as entering private dwellings is concerned, must have regard to both constitutional and legislative provisions, " a department spokeswoman told the Sunday Tribune this weekend. The constitution provides for the protection of the "inviolability of private dwellings", saying they can't be forcibly entered "save in accordance with the law".

Under existing workers' protection legislation, including the national minimum wage and the Protection of Young Persons Act, the department's labour inspectors cannot enter a private house "except by invitation or by a warrant of the District Court", the spokeswoman said.

"Such warrants may only be issued if a judge of the District Court is satisfied on the sworn information of an inspector that there are reasonable grounds for suspecting that information required by an inspector is held on any premises or any part of premises."

It is understood department officials believe a judge would be loath to give the go-ahead to inspectors to enter a private home forcibly. However, other state agencies don't appear to have the same qualms about knocking on hall doors to ensure their various laws and regulations are upheld.

Officers of the Environmental Protection Agency can enter a private house as long as they give the householder 24 hours' notice of their visit, according to an EPA spokeswoman.

While the EPA is mainly concerned with pollution and illegal dumping by large businesses and farms, householders also have obligations and can't, for example, burn certain substances in their back gardens.

And while the EPA rarely visits private dwellings, the 1992 act which set up the agency specifically included a clause allowing home inspections on the basis that the country's 1.5 million homes were a significant source of pollution and needed to be controlled.

Ordinary householders can also be visited by a health and safety inspector if they hire builders. A spokesman for the Health and Safety Authority, which polices the increasing number of safety regulations, confirmed that if a homeowner hires builders, he is then making his house a workplace and is subject to health and safety regulations. "Health and safety inspectors not only have the authority to enter homes that have become a workplace, but they are obliged to do so if they believe the regulations are being broken, " said the HSA spokesman.

Now, even handymen hired by homeowners to trim high hedges or clean windows are subject to new regulations protecting those working at a height. The HSA spokesman said these new regulations would be applied with "common sense".

Meanwhile, an 80-year-old piece of legislation allows ESB workers to enter a private house if they have a reasonable suspicion that a person is stealing electricity. "This was common practice in the early years of the ESB when people bypassed the meter and connected directly onto the mains, " said an ESB spokesman. "It is rare enough today but we have had reason to enter houses recently and we have secured convictions for the theft of electricity."

Householders can relax, however, if they are engaging in smoking or cooking. Both the Office of Tobacco Control and the Food Safety Authority say they have no jurisdiction over private houses.