Anyone who has ridden an escalator and bothered to pay attention has seen - and likely ignored - little signs suggesting riders hold the grimy handrail.
In Montreal's subway system, the friendly advice seems to have taken on the force of law, backed by a $100 fine.
Bela Kosoian, a 38-year-old mother of two, says when she didn't hold the handrail Wednesday she was cuffed, dragged into a small holding cell and fined.
"It was horrible, disgusting behaviour [by police]" said Ms. Kosoian, a 38-year-old student of international law. "I did nothing wrong. They should go find the guys who stole my tires off the balcony."
Ms. Kosoian, who studies at the Université du Québec à Montreal, was riding an escalator down to catch a 5:30 p.m. subway from the suburb of Laval to an evening class downtown when she started rifling through her backpack looking for a fare.
Ms. Kosoian, who grew up in Georgia when it was still part of the Soviet Union, says she didn't catch the officer's instruction to hold the rail when he first approached.
When he told her again to hang on, she says she replied, "I don't have three hands." Besides, she had been sick and feared catching a new bug.
That's when the officer demanded identification so he could write her ticket, she said.
Ms. Kosoian started arguing. The officers handcuffed her and threw her into a small holding cell. The officers searched her bag and gave her a $100 ticket for failing to hold the banister and another $320 ticket for obstruction.
The handcuffs bruised Ms. Kosoian's wrists and an officer's boot scraped skin off the top of her foot.
She intends to fight the tickets.
Société de transport de Montréal regulations say "it is forbidden for all persons to disobey a directive or a pictogram posted by the Société."
At the top of the escalator in the Montmorency station, a small sign indeed shows a stick man holding a railing with the words, "Hold the handrail."
Montreal's metro system is policed by transit inspectors and local police departments.
Isabelle Tremblay, a spokesperson for the STM, seemed relieved to establish late yesterday that Laval police stopped Ms. Kosoian.
"We were quite surprised to hear about this, we don't give fines for such things," Ms. Tremblay said.
Laval police were unable to provide an explanation yesterday.
As Ms. Kosoian noted, Montreal's subway takes bicycles, strollers and babies but has few elevators, making banister-holding an unlikely juggling act for many.
Transit systems across Canada have struggled with innocent-sounding behaviour that can cause accidents.
A couple years ago, Toronto transit authorities removed signs urging escalator riders to stand on the right, walk on the left, because walking on escalators caused dozens of injuries. Walkers were not fined.
In the Vancouver region, officials will soon launch a campaign to discourage running, sliding down banisters and other risky behaviour.
"We do tend to tear our hair out sometimes at the ways people get hurt," said Drew Snider, a spokesman for the regional transportation authority.
In Montreal, 16 students were injured in 2004 when an escalator suddenly stopped.
As for fears of catching another flu, a leading germ expert says you are more likely to fall down an escalator than catch illness from a handrail.
"No matter how dirty your hands become, all you have to do to avoid getting ill is wash your hands," said Dr. Philip Tierno, the author of The Secret Life of Germs .
"Safety is first. If you break your head or break your neck, you don't have to worry about washing your hands."