7.1.4 Standard Characters
The standard-chars element type form declares the names of characters in the character repertoire which correspond to characters defined in ISO/IEC 10646-1 or ISO/IEC 6429. A character in ISO/IEC 10646-1 or ISO/IEC 6429 is identified by its code in the corresponding character set, called its universal code.
The content of the element shall be a list of pairs of character names and numbers expressed in decimal.  It declares that each character name corresponds to the character with the universal code specified by the following number.
A process specification shall declare character names for each of the following character numbers in ISO/IEC 10646-1: 32 (space), 34 (quotation mark), 35 (number sign), 39 (apostrophe), 40 (left parenthesis), 41 (right parenthesis), 42 (asterisk), 43 (plus sign), 45 (hyphen-minus), 46 (full stop), 47 (solidus), 48 to 57 (digit zero to digit nine), 58 (colon), 59 (semicolon), 60 (less-than sign), 61 (equals sign), 62 (greater-than sign), 63 (question mark), 65 to 90 (Latin capital letter A to Latin capital letter Z), 92 (reverse solidus), and 97 to 122 (Latin small letter a to Latin small letter z). It shall also declare character names for each of the following character numbers in ISO/IEC 6429: 10 (line feed), and 13 (carriage return).
It shall be an error for a single character name to occur more than once in the standard-chars elements in a single part.  The declaration for a character name in one part in the standard-chars element type form takes precedence over any declaration for that character name in any later parts.
A system may inherently know for a base character set identified by a public identifier with an ISO owner identifier how bit combinations in that character set correspond to universal codes.  Thus, if a base character set has a formal public identifier that includes an ISO owner identifier, and, for each character used by the document character set from that base character set, exactly one character name is declared using the standard-chars element type form, then no baseset-encoding element type form is required for that base character set.