Hamilton City Council staff will be trained to spot spy cameras in facilities including toilets.

​Hamilton toilets and public changing rooms will be routinely swept for spy cameras.

City council staff and cleaning contractors will be trained on how to spot clandestine cameras in an effort to protect people from peeping toms and online perverts.

It follows similar moves by councils nationwide.

In North Canterbury, council staff check pool-changing rooms every three hours for hidden cameras after concerns were raised about covert filming.

In the past three years, five people have been convicted in the Waikato for making secret recordings, while nationwide, 105 people have been caught spying on unsuspecting victims.

But one security expert said authorities face an uphill battle protecting the public from depraved voyeurs with ready access to a range of spying devices.

Hamilton City Council staffer Mary Birch said no spy cameras had been found in council facilities to date.

Even so, staff at venues such as Waterworld and Hamilton Gardens will be trained on how to find hidden cameras.

"The very design and basic layout of our toilets and changing facilities, particularly at our pools sites, would make it very difficult to install a camera or a recording device," Birch said.

"However, to ensure the safety of our customers and our staff, we will be working closely with staff and cleaning contractors to introduce processes to check for these sort of devices across the facilities.

"We'd like to thank the Waikato Times for raising this with us and will be diligent in our awareness of this possible risk to our customers and visitors."

In 2014, Waimakariri District Council introduced security sweeps of its pool-changing rooms in response to concerns about covert filming.

The council also banned the use of mobile phones in changing rooms.

Most mobile phones can take photos and make video recordings.

Chris Mangan, chief executive of Waikato Security Services, said his company was sometimes asked by corporate organisations to check their premises for secret recording devices.

The requests often followed the discovery of secret recording equipment at public venues.

"That's when you get a business thinking, hell, if it could happen there, how easily could it happen at our business?" he said.

Mangan sympathised with those who want stricter controls around the sale of covert devices, but said such controls would be difficult to enforce.

Retailers such as Jaycar Electronics sell a range of spy cameras, ranging from pen video cameras to spy keyrings and watches.

On Trade Me, users can buy cameras disguised as sunglasses, wall clocks and baseball caps.

"The thing with these devices is they're discreet and can easily be carried across the border without anybody knowing," Mangan said.

"It would be like saying you can't sell blue pens any more. The biggest challenge in detecting these cameras is they can be put into anything, such as smoke detectors or alarm sensors. Listening devices are easier to detect because you can pick up their frequency, but even they are getting more difficult to detect."

If people are concerned about the presence of a spy camera, they should look for something that appears out of place or stands out from its surroundings.

Daniel Toresen, of Auckland private investigations company Thompson & Toresen, has been employed by four organisations in the past six months to check for covert cameras.

In two cases, cameras were found concealed inside the company's premises.

The lens of spy cameras can be as small as a pinhead and are relatively cheap to buy, Toresen said.

Covert cameras disguised as clothes hooks, tissue boxes and mirrors can be purchased from numerous Chinese-based websites.

"You have to ask yourself, what is the purpose of a covert camera in a changing room clothes hook?" Toresen said.

In 2014, a Waikato man set up a camera in an air-freshener container in his bathroom to spy on his daughter and two friends.

People convicted for intimate visual recording offences

2013 2014 2015

Hamilton District Court 1 1 3

Nationally 41 25 39