The Eleventh Circuit denied consolidated petitions for review filed by various railroads and industry associations challenging the Federal Railroad Administration’s (FRA) “Crew Size Rule,” which generally requires freight trains to operate with a minimum of two crewmembers. The court held that the FRA acted within its statutory authority under the Federal Railroad Safety Act of 1970, rejecting the argument that the phrase “as necessary” in 49 U.S.C. § 20103(a) imposes an evidentiary bar requiring proof that a rule is essential to safety; instead, the court interpreted the phrase as granting the agency discretion to regulate when reasonably related to railroad safety. Applying the Administrative Procedure Act’s arbitrary and capricious standard, the court found the FRA’s decision reasonable based on its consideration of public comments regarding human error and fatigue, research on cognitive demands, trends in increasing train lengths, and uncertainties surrounding Positive Train Control technology. The court further ruled that the 2019 Withdrawal Order did not constitute a binding prior policy triggering a heightened change-in-position doctrine because it had been vacated by the Ninth Circuit, and even if it did, the FRA provided a reasoned explanation for its reversal based on reassessed safety concerns. Additionally, the court determined that *Michigan v. EPA* did not compel a formal cost-benefit analysis requiring the inclusion of foregone labor savings, and found no conflict between the Crew Size Rule and the Rail Safety Improvement Act’s risk reduction program. Finally, the court held that the FRA’s failure to finalize the rule within the statutory 12-month deadline did not warrant vacatur, as the statute lacked a specified consequence for noncompliance. The petitions were denied, leaving the Crew Size Rule in effect.