ISO 259-2 simplifies the diacritical signs for vowels of ISO 259, and is designed for Modern Hebrew.
ISO 259-3 is Uzzi Ornan's romanization, which reached the stage of an ISO Final Draft (FDIS) but not of a published International Standard (IS). It is designed to deliver the common structure of the Hebrew word throughout the different dialects or pronunciation styles of Hebrew, in a way that it can be reconstructed into the original Hebrew characters by both man and machine.
It is neither a character-by-character transliteration nor a phonetic transcription of one pronunciation style of Hebrew, but is instead phonemic from the view point that all the different dialects and pronunciations of Hebrew through the generations can be regarded as different realizations of the same structure, and by predefined reading rules every pronunciation style can be directly derived from it.
Each consonant character in the Hebrew script is converted into its unique Latin character. ISO 259-3 has five vowel characters, corresponding to the five vowel phonemes of Modern Hebrew: a, e, i, o, u. In addition there is a sixth sign for denoting the vowel /ej/ or /e/ that is written followed by ⟨י⟩ in common Hebrew spelling: ei.