A piece of overhead equipment on a Muni bus malfunctioned Thursday evening, turning it into a dangerous projectile that shattered the window of a business in the city's Financial District and nearly struck an employee sitting inside.
The incident occurred around 6:15 p.m. Thursday at 1 Bush St., Muni spokesman Paul Rose said Friday.
A bus was traveling nearby when a "shoe," the piece of equipment that connects the vehicle to overhead wires, got caught in a guide wire, creating a spring action that sent the equipment flying into the building, Rose said.
The equipment shattered a window on the third floor of 1 Bush St. and narrowly missed an employee sitting at a desk in the office of the architecture firm HOK, according to employees at the company.
"This rarely happens," Rose said.
He said the last time the agency was aware of a similar incident in the city was three years ago.
"These types of things are inspected every single day before the vehicle starts down on their run," he said. "Following this incident, we're going to review our maintenance procedures and operations procedures."
Rose said Muni officials are working with building management to replace the window. Officials at Tishman Speyer, the company that manages the property, were not immediately available.