The board at its first meeting, and thereafter annually at the first meeting in January, shall elect a vice chair who shall preside in the absence of the chair. In the event of the absence or inability to act by the chair or vice chair, the chair pro tempore shall preside.
Source:
Section 120100, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=PUC§ionNum=120100..