Flagger training and certification requirements
From California MUTCD, Section 6E.01 Qualifications for Flaggers:
“02 Flaggers shall be trained in the proper fundamentals of flagging moving traffic before being assigned as flaggers.
03 Documentation of the training shall be maintained as required by Injury Illness and Prevention Program of the General Industry Safety Order in the California Code of Regulations (Title 8, Division 1, Chapter 4, Subchapter 7, Section 3203).
04 Flaggers shall be trained by persons with the qualifications and experience necessary to effectively instruct the employee in the proper fundamentals of flagging moving traffic.”