A Vallejo man working at a St. Helena winery died after falling 16 feet through a roof, according to the Napa County sheriff’s office.

Daniel Mario Colombo, 56, of Vallejo was a pipefitter and welder working Thursday at the Sutter Home Winery on Main Street. He was making repairs on the refrigeration system and was on the roof, according to Napa Sheriff’s Capt. Steve Blower.

Colombo wasn’t wearing a safety harness when he fell through a fiberglass light panel. He died at 12:40 p.m., Blower said.

The industrial death was being investigating by Napa County District Attorney’s Office and Cal-OSHA.

You can reach Staff Writer Randi Rossmann at 707‑521-5412 or randi.rossmann@pressdemocrat.com. On Twitter@rossmannreport.