Mountain View firefighters posted photos and a tribute to Desimone on the fire department's Facebook page, thanking him for his help with the annual pancake breakfast.
"Josef believed in giving back to the community and was an integral part of our annual Pancake Breakfast team. We will miss Josef's big smile, larger than life personality, and commitment to giving back to the community," the post said.
Zuckerberg described "Chef Josef," who worked for the Menlo Park company since 2008, as a "Facebook legend and institution." Off the job, he exemplified a commitment to "giving back more in life than he took," Zuckerberg wrote. "Almost every weekend he was volunteering with veterans' organizations, hosting firefighter breakfasts or supporting some other valuable cause."
A Facebook post by the company's chief operating officer, Sheryl Sandberg, described Desimone as "a dedicated colleague who cared deeply about all of those around him, a perfectionist who worked hard each day to give his very best to his community, and an inspiration."
Details of the accident were unavailable as of Tuesday morning, July 23.