NEW YORK (CBSNewYork) — The New York City Department of Transportation has unveiled its new 25 mph speed limit signs, and the new speed limit is law effective Friday.

Mayor Bill de Blasio last month signed a measure reducing the city’s speed limit from 30 mph to 25 mph. The City Council passed the measure as part of the mayor’s “Vision Zero” plan to reduce traffic deaths.

“I think there’s a real consensus in this town that we need to have people drive more carefully, more safely, and slower for the protection of our kids, our seniors,” the mayor said.

As CBS2’s Matt Kozar reported, the idea behind the law is to reduce traffic fatalities, but some New Yorkers weren’t happy with the new law.

“I think it’s just a catch 22 to make some more money for the city,” Alberto Rodriguez said.

Others applauded the move.

“They’re really fast out here, and they don’t pay attention. It’s kind of dangerous,” Kassandra Ramirez said.

Cabbie Ruval Ahmed said that if he drives too slow his customers will get mad, but if he drives too fast he’ll get a ticket.

“Police always follow the cab drivers,” he said.

DOT Commissioner Polly Trottenberg said the new speed limit is more about saving lives and not handing out tickets.

“We’re not trying to engage in a game of ‘gotcha’ here, so we really make sure we do a public education campaign,” she told reporters, including WCBS 880’s Marla Diamond. “We’re going to seek to put signs in key corridors and in areas where particularly there has been a high rate of crashes or a lot of speeding. So we really want to do our best to educate people.”

The new default speed limit, which goes into effect Friday, will apply to all streets where no other limit is posted. Highways and parkways will still have higher limits, and school zones will have lower limits.

“When you lower the speed limit from 30 to 25, if there’s a collision, you cut in half the chances it will result in a fatality,” Trottenberg said.

Trottenberg said 89 signs will be going up along the city’s borders as well as bridges, highway ramps and other “key gateways to the city.”

“We’re also going to be putting them, for example, to remind people where you would get a rental car at the airport,” she said. “Make sure people coming into the city know what the speed limit is.”

Trottenberg admitted it may take time to change drivers’ behaviors.

“You will get where you’re going,” she said. “Traffic will continue to flow in New York, we believe that. Most of what actually slows you down in this city is, as you know, when you’re at a light or when there’s double parking. The speed limit is often not the determining factor.”

The DOT commissioner noted that the city’s speed limit was 25 mph until the state Legislature increased it 50 years ago.

The city will also be recalibrating its thousands of traffic signals.

For more information about the new speed limit, click here.

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