49 CFR 220.29
§ 220.29 Statement of letters and numbers in radio communications.
United States · 49 CFR — Transportation · Status: effective
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- Citation
- 49 CFR 220.29, § 220.29 Statement of letters and numbers in radio communications, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/258256
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Full text
(a) If necessary for clarity, a phonetic alphabet shall be used to pronounce any letter used as an initial, except initial letters of railroads. See appendix A of this part for the recommended phonetic alphabet.
(b) A word which needs to be spelled for clarity, such as a station name, shall first be pronounced, and then spelled. If necessary, the word shall be spelled again, using a phonetic alphabet.
(c) Numbers shall be spoken by digit, except that exact multiples of hundreds and thousands may be stated as such. A decimal point shall be indicated by the words “decimal,” “dot,” or “point.” (See appendix B to this part, for a recommended guide to the pronunciation of numbers.)
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.