StacksVerified U.S. regulatory reference

49 CFR Part 220, Appendix B

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov

To distinguish numbers from similar sounding words, the word “figures”should be used preceding such numbers. Numbers should be pronounced as follows:

NumberSpoken
0ZERO.
1WUN.
2TOO.
3THUH-REE-.
4FO-WER.
5FI-YIV.
6SIX.
7SEVEN.
8ATE.
9NINER.

(The figure ZERO should be written as “0” to distinguish it from the letter “O”. The figure ONE should be underlined to distinguish it from the letter “I”. When railroad rules require that numbers be spelled, these principles do not apply.)

The following examples illustrate the recommended pronunciation of numerals:

NumberSpoken
44FO-WER FO-WER.
500FI-YIV HUNDRED.
1000WUN THOUSAND.
1600WUN SIX HUNDRED.
14899WUN FO-WER ATENINER NINER.
20.3TOO ZERO DECIMALTHUH-REE.