Chief Bigelow began his CAL FIRE career in 2004 as a Fire Fighter I at the Ahwahnee station in MMU, where he spent five seasons as a nine-month seasonal. In 2009, he promoted to a Fire Apparatus Engineer at the Coarsegold station also in MMU. In 2013, Frank promoted to LT Fire Captain at the Columbia Air Attack Base in TCU working as the Air Tanker Base Manager. At the end of the 2013 fire season, he accepted a permanent Fire Captain position in MMU as the Pre-Fire Engineer. In 2017, he promoted to Battalion Chief as the Southern Region Pre-Fire Coordinator. Frank then promoted to the Deputy Chief, of the then called, Wildfire Prevention Engineering in the Office of the State Fire Marshal in 2020, where he oversaw five statewide programs. In 2021 he accepted a Staff Chief position in the newly created Community Wildfire Preparedness & Mitigation Division overseeing eight statewide programs.

In 2023 Frank accepted the assignment as Acting Deputy Director of Community Wildfire Preparedness & Mitigation.