An Australian rail company has fitted a device that can tell whether graffiti is being sprayed or applied inside train carriages and alert police.
The technology, called Mousetrap, uses chemical sensors to detect the vapour of spray paint and permanent marker and relays the data back in real time to mobile equipment held by rail staff or police, triggering the capture of CCTV images.
Sydney Trains has been testing the technology and its chief executive, Howard Collins, told Guardian Australia the devices could be moved around the network’s 160 operating trains to keep offenders from knowing which trains carried them.
The device had been developed especially for the city’s rail network, and trialled for 18 months on dozens of trains. It has led to the arrest of more than 30 offenders to date.
Collins believed the $500,000 price tag of the new technology has been “value for money” but that it was too early to say if the devices had led to a drop in offences.
Removing graffiti from the Sydney trains network cost $34m in 2014 and trains are defaced with 11,000 graffiti tags each month.
Collins said: “We will look at the return on investment ... and whether all our trains should have this device installed.”
Collins described the device as small, free of external wiring, and hidden from sight.
When asked about the possibility spray can makers could create a product that could not be detected by the device, Collins said the public transport department always tried to ensure it was “one step ahead” of vandals.
“I’ve been around public transport for a long time, and in my early days it was spray paint, then leather dyes, then permanent markers and scratching into windows. The technology moves on, as well as the ingenuity of vandals,” he said.
The trial will continue for another year.
