MONTREAL -- Canadian municipalities have been accelerating the fight against graffiti by requiring new transit vehicles to contain built-in protections to minimize the street art considered an urban scourge by some.

Montreal's new Metro cars and Toronto streetcars -- along with transit vehicles in Vancouver and Edmonton that have been ordered from Bombardier, the world's largest maker of railway transit vehicles -- are delivered installed with some level of protection, ranging from gel coatings that protect panels to plastic films that limit damage to windows.

Transit authorities around the world are increasingly requiring manufacturers to provide designs that tackle the prospect of their vehicles being vandalized, Marc-Andre Lefebvre, spokesman for Bombardier, said in a recent interview.

"It's common all over the world .... Almost all our customers do require a certain level of protection or resistance," he said.

Bombardier says the best exterior protection involves using stainless steel on vehicles like the new Toronto subway cars known as the Toronto Rocket and Montreal suburban AMT trains.

Interior protection depends on how much the customer is willing to spend given their previous experiences with vandalism. But so-called scratchitti, in which vandals uses knives or other tools to carve into windows and panels, is an evolving concern, Lefebvre said.

Bombardier isn't alone. Other large manufacturers also use materials from suppliers including 3M and Dupont to meet customer demand, Lefebvre said.

Montreal's transit authority and the Toronto Transit Commission have also sought help to protect existing vehicles.

Plas-Tech based in Concord, Ont., won a $591,000 contract from Montreal to supply 3M anti-graffiti film. The four-ply ultra-thin material affixed to windows and clear dividers near exits can be peeled off when damaged, and replaced by transit staff.

"It just increases the life of that window that much longer," said Mike Aube, the company's sales manager.

Some studies have suggested graffiti vandalism costs taxpayers around the world billions of dollars a year to clean up.

New York City says it spent about $1 million in 2014 to clean North America's largest subway system, some 25 years after it aimed to become graffiti-free. At the height of the problem, subway cars were so tagged that it was nearly impossible to see out the windows as ridership plunged and crime soared, it said.

Montreal says graffiti removal costs are part of the transit system's overall $20 million per year station maintenance budget.

Like most transit systems, Canada's second-largest says it tries to discourage vandalism by removing graffiti in less than a day. Hate-fuelled tags are also reported to police.

Calgary recently dealt with racist graffiti on property and cars at a LRT station that disparaged and threatened Syrian refugees and Muslims. That was five years after Calgarians listed graffiti vandalism in a police survey as one of the Top 10 safety/crime issues in the city.

Toronto stepped up its efforts to tackle vandalism after its general manager arrived in 1995 after running New York's transit system.

But major incidents in Toronto have been on the rise for most of the decade, peaking at 67 in 2014 from 13 in 2008. They were down slightly to 54 in 2015.

Vancouver's TransLink said it boosted overnight security patrols around train storage depots and quickly removes graffiti from vehicles. It also apples a coating to protect paint on train exteriors and a protective anti-scratch coating on the inside of windows.