Under Gov. Code 11507 and 8 Cal. Cod. Regs. 371.2, Cal. OSHA may amend its accusation against an employer for safety violations before or during the administrative hearing so long as the employer is not prejudiced by the amendment.  This decision affirms the Cal. OSHA Appeals Board’s decision that the amendment of the accusation to allege a violation of a different statutory section arising from the same basic facts did not prejudice the employer.  So long as the facts remain the same, a change in legal theory is not prejudicial.  Here, the accusation charged a fall from an unguarded stairway landing whereas the amendment charged a fall from an unguarded floor opening.