Here’s some advice: Don’t climb off a subway platform and onto the tracks.

It would seem to go without saying — like, Don’t stick a barbeque fork in your eye. “But you’d be surprised,” says Kevin Ortiz, a spokesman for New York’s subway system, where 52 people have been struck and killed by trains this year. About half the deaths were accidental, the victims in many cases having scampered down to the tracks to retrieve personal belongings they dropped. “You spend a couple of hundred bucks for an iPhone,” Ortiz says, “you see it lying there, it’s important to you …”

And thus is born a dumb idea.

The continuing fatalities (there were 55 in 2012) prompted New York’s Metropolitan Transportation Authority to produce a fairly harrowing, minute-long public-service video that was posted last week on the MTA’s YouTube channel, starring Ortiz in an understated (that is, wordless) performance as a subway patron who’s a bit too fond of his mobile device.

So, did the not-very-agile Kevin manage to save himself and get on with his day? “Oh, he made it,” says Ortiz, tongue planted firmly in his New Yorker cheek. “He did one of those last-minute back flips you see in ‘The Matrix’ — landed on the platform just in time.”

With about 1.6 billion passenger-trips annually, New York’s subway is by far the nation’s busiest. In addition to the 52 people fatally hit by trains this year, Ortiz says, more than 90 rail patrons have been injured, some of whom were standing too close to the edges of platforms as trains rumbled into stations.

Metrorail, with well more than 200 million passenger trips annually, is typically America’s second busiest subway. This year, eight people have been hit by trains in suicide attempts, three of them fatally, according to a Metro spokesman. In a ninth incident, in August, a 21-year-old George Mason University student walking in darkness along outdoor Orange Line tracks was accidentally struck and killed by a train near the East Falls Church station.

And, last year, there was the woman featured in this video — a 37-year-old newcomer to the United States who got a little mixed up at Metro Center. Looking for a Glenmont-bound Red Line train and realizing she was on the wrong side of the station, she decided to take a shortcut across the tracks, eventually alighting on a catwalk, which she mistook for a platform.