One specific kind of turn is being blamed to have caused the death of many, a road safety policy in San Francisco, Vision Zero, which aims to stop the city’s traffic casualties, said in a report.

“40% of traffic deaths in San Francisco in 2019 were caused when drivers made left turns and didn’t see the person in the crosswalk… until it was too late,” its new report, which used the San Francisco Department of Public Health data, said, as reported by SFGATE.

Thirty-one percent of the pedestrians of old age are killed in left-turn circumstances, the report added.

Each year, more than 300 people using the crosswalks sustain injuries because of drivers making a left turn at intersections.

“Left turn collisions are an intersection design problem, but they are also a driver decision-making problem. So solutions will also need to be multifaceted,” according to the report.

The Safer Intersections Project was unveiled by the San Francisco Municipal Transportation Agency (SFMTA) in a bid to use new ways to the city’s intersection design. The said project was done following a five-year analysis of data that cited the problem on the left turn in 2018.

“Drivers need to judge many factors simultaneously when making a left turn. Given the complex decisions that have to be quickly made in a stressful environment, we can’t assume drivers will always make rational decisions when making a left turn,” part of the report from Vision Zero said. “Some may drive too fast and cut corners too closely.”

Last fall, vertical delineator posts that are waist-high were installed at seven intersections as part of the left turn traffic-calming engineering project.

Added to this, the center of the roadway close to the crosswalks was equipped with small rubber speed bumps for enhancement. The paint was also applied to prevent sharp left turns that can push the cars early into the crosswalks.

The approach became effective as there was a 17 percent drop in average car speed and a 71 percent decrease in the chances of vehicles making a left turn at over 15 mph. Similar methods are being planned by the SFMTA to be done in 35 more intersections in the city.