To obtain review of an OSHA Appeals Bd. decision, the aggrieved party must petition the Appeals Bd. for reconsideration of the underlying decision (whether of an ALJ or the Appeals Bd.), but this decision holds, there can be no second petition for reconsideration unless (a) on the first reconsideration the Appeals Bd. reverses the underlying decision, thus creating a new aggrieved party, (b) on the first reconsideration, the Appeals Bd. hears new evidence on which it bases its decision on reconsideration, or (c) the decision on reconsideration goes outside the issues framed by the parties. Here, none of those exceptions applied, the Appeals Bd. affirmed the ALJ’s decision based on the evidence before the ALJ. So the employer’s second petition for reconsideration was a nullity and didn’t extend the 30-day deadline for filing a petition for writ of administrative mandate under Lab. Code 6627, which governs review of OSHA Appeals Bd. decisions. However, the 30-day filing deadline is subject to equitable tolling under the rule announced in St. Francis Memorial Hospital v. State Dept. of Public Health (2020) 9 Cal.5th 710, so the trial court should have granted the petitioning employer leave to amend its petition to invoke that doctrine if it can.