US lawFederal (United States)RegulationsTitle 49 CFR — TransportationChapter VIII — NATIONAL TRANSPORTATION SAFETY BOARDPart 821 — RULES OF PRACTICE IN AIR SAFETY PROCEEDINGSSubpart B — General Rules Applicable to Petitions for Review, Appeals to the Board, and Appeals From Law Judges Initial Decisions and Appealable Orders821.2149 C.F.R. § 821.21Official notice.Last amended: 2016Year: 2026Length: 42 wordsOfficial source Cite as 49 C.F.R. § 821.21 (2026)Where a law judge or the Board intends to take official notice of a material fact not appearing in the evidence in the record, notice shall be given to all parties, who may within 10 days file a petition disputing that fact.Previous49 C.F.R. § 821.20