REPORT ON THE CURRENT STATUS OF
UNITED NATIONS ROMANIZATION SYSTEMS FOR GEOGRAPHICAL NAMES
Compiled by the UNGEGN Working Group on Romanization Systems
Version 2.2c, May 2004
The United Nations recommended system was first approved in 1967 (resolution I/14), based on the modified general system of the Royal Institute of Thailand. The table and notes on its application were published in vol. II of the conference reports (United Nations Conference on the Standardization of Geographical Names. Geneva, 4-22 September 1967. Vol. II. Proceedings of the Conference and technical papers, pp. 122-123). A revised version of the system was officially endorsed by the government of Thailand in 2000. This was approved at the Eighth United Nations Conference for the Standardization of Geographical Names in Berlin, 2002, based on a document submitted by Thailand (Principles of Romanization for Thai Script by Transcription Method. Eighth United Nations Conference on the Standardization of Geographical Names. Berlin, 27 August – 5 September 2002. Document E/CONF.94/INF.41).
Thai uses an alphasyllabic script. In Thai writing word division is not ordinarily indicated which may complicate the romanization. The romanization system is not reversible to its original script form.
Thai characters are romanized in two ways depending on whether they denote syllable-initials or syllable-finals. The romanization of syllable-finals is indicated in parentheses.
Vocalic nuclei and special characters (ก stands for any consonant character)
Notes (Notes 1-5 have been adapted from Principles of Romanization for Thai Script by Transcription Method. Eighth United Nations Conference on the Standardization of Geographical Names. Berlin, 27 August – 5 September 2002. Document E/CONF.94/INF.41.)
The transliteration of Thai in the standard ISO 11940:1998 (This is a modification of a document presented in 1992: Romanized Transliteration of Thai. Sixth United Nations Conference on the Standardization of Geographical Names. Vol. II. Technical papers. New York, 25 August - 3 September 1992, pp. 369-379. Some consonants have been given revised equivalents in the ISO standard) gives each Thai character a unique equivalent in the Roman script (a single letter or a combination of a letter plus a "modifier letter"). The Thai characters are transliterated strictly in the order they are written, diacritical marks accompanying a consonant are transliterated starting by the uppermost mark and finishing with the subscript mark. As an example, here are some transliteration equivalents: ก k, ข k̄h, ฃ ḳ̄h, ค kh, ฅ k’h, ฆ ḳh, ง ng; ะ a, ั ạ, า ā, ำ å, เ e, แ æ, etc.