Worker crushed to death dismantling BottleRock structure

Promotion volleyballs bounce above the crowd during a performance at the BottleRock 2016 festival in Napa. A worker was crushed to death while dismantling the VIP lounge on Tuesday. Promotion volleyballs bounce above the crowd during a performance at the BottleRock 2016 festival in Napa. A worker was crushed to death while dismantling the VIP lounge on Tuesday. Photo: Michael Noble / The Chronicle Photo: Michael Noble / The Chronicle Image 1 of / 90 Caption Close Worker crushed to death dismantling BottleRock structure 1 / 90 Back to Gallery

A 36-year-old construction worker dismantling a structure at the BottleRock festival in Napa died after being crushed by a metal beam, firefighters said.

The man, identified as Sonoma resident Mateo Zavaleta Zarate, was breaking down an A-frame tent over the festival’s VIP lounge at Napa Valley Expo when he was hit by a metal arch around 5 p.m. Tuesday, officials with the Napa Fire Department said. The popular music festival ended Sunday.

Fellow workers with Top Productions in Richmond, including Zarate’s brother, ran to the victim’s aid before paramedics rushed him to Queen of the Valley Medical Center in Napa, where he was pronounced dead at 5:41 p.m. Tuesday, officials said.

Investigators from Cal/OSHA, the state’s workplace safety agency, will be looking into the accident to see if any regulations were violated.

Evan Sernoffsky is a San Francisco Chronicle staff writer. Email: esernoffsky@sfchronicle.com Twitter: EvanSernoffsky