King County Metro and Community Transit will beta-test alarms that flash when people approach the driver’s blind spots. Metro has averaged 24 bus-pedestrian crashes a year over the last decade.

Share story

In an experiment to reduce lethal crashes involving pedestrians, Washington state transit agencies have equipped 38 buses with dashboard alarms that flash when people are walking in the driver’s blind spots.

Window frames and mirrors can hide as many as a dozen people as a bus turns left through a crosswalk.

The risks are compounded by distracted pedestrians in the streets, as well as traffic stress on bus drivers, who fall behind schedule and angle for passages.

The study begins this month at King County Metro Transit, Community Transit, Pierce Transit, Kitsap Transit, Intercity Transit in Olympia, C-Tran in Vancouver, Ben Franklin Transit in the Tri-Cities and Spokane Transit.

When a bus is within three seconds of possibly hitting someone, a yellow human-shaped icon will flash on the left, center or right dashboard. At one second, the icon turns red, and an alarm sounds.

Funding for the $225,000 project includes $100,000 from the National Academy of Sciences and $80,000 from the Washington State Transit Insurance Pool.

Five months of data will be analyzed by University of Washington professor Yinhai Wang, who said Minnesota is working on a similar test. California and Ohio are also considering these systems, said Jerry Spears, the insurance pool’s deputy director.

Washington’s study comes two months after a left-turning bus struck and fatally injured a 94-year-old woman next to the Northgate Transit Center. The accident investigation hasn’t been completed, said Kevin Desmond, King County Metro general manager.

Metro alone has averaged 24 bus-pedestrian crashes per year, of all types, over the last decade.

“It is the text message, the page I do not want to get — pedestrian accident,” Desmond said. “Without hesitation, I see that as the safety issue above all others, and I know we can prevent some of them.”

Worldwide, some 600,000 cyclists and pedestrians are killed by large vehicles yearly, says Mobileye, which along with Rosco Vision Systems is developing the technology.

Besides casualties to pedestrians, and psychological trauma to bus drivers, these collisions have brought insurance losses of up to $5 million, the insurance pool says.

Last fall, Metro paid a $2 million after mediation, to a man who was hit by a right-turning bus and suffered many broken bones, Jan. 3, 2014, on Fourth Avenue South in Sodo. Metro in 2014 also instituted yearly pedestrian safety training for drivers.

The Mobileye technology costs $3,500 per vehicle during the pilot project, including cameras outside the bus to detect people and distances.

Other dashboard displays flash when a bus exceeds speed limits by 5 mph, or follows a vehicle too closely.

“There’s no doubt these technologies will be very helpful for improved transportation safety,” Wang said.

He foresees two challenges in the test. If alarms flash constantly, in busy areas such as Seattle’s Pike-Pine and Rainier Beach neighborhoods or in Tukwila, drivers may become annoyed. Or there could be false negatives, for instance if a skateboarder appears too suddenly to trigger the initial three-second warning. Wang hopes brake or G-force sensors can record emergency stops even if alarms didn’t flash.

Brian Sherlock, safety researcher for the national Amalgamated Transit Union, says he thinks the alarms will be ineffective, because people can step off a curb into the path of a bus in an instant.

Unlike some car-safety systems, these alarms won’t slow or stop the bus.

And by the time the red icon shows up, it’s too late — unless the bus is coasting at 5 mph or less, a Community Transit training video says.

Driver skill is vital.

Transit operators are taught to “rock and roll,” leaning in their seat to see past the vehicle’s A pillars, which frame the windshield on the left and right corners. They should avoid what Desmond calls the “lazy left turn.” Whenever a bus makes a 90-degree turn, the driver experiences fewer blind spots, he said, compared to a banana-shaped turn.

Among other ideas, Metro equipped buses with exterior speakers that featured a female voice, saying, “Caution, bus is turning.” Results from that one-month experiment will be issued next year with the bus-alarm findings, Desmond said.

Also, Metro’s new trolley buses position the right mirror high, and the left mirror below shoulder level, to avoid obscuring pedestrians. The transit union is lobbying for thinner or reshaped A pillars. Even if manufacturers agree, it takes 13 to 17 years to retire and replace an urban bus fleet.

For that reason, the transit-insurance execs are more enthusiastic about high-tech alarms.

They’re just around the corner.