If an HL7 message contains one of the special delimiter characters as part of its message content, you can use a special escape sequence to specify the delimiter character. This ensures that any application that processes HL7 messages can always distinguish between a delimiter character and a character that is part of the message text.
Each delimiter character has its own escape sequence. This escape sequence consists of the \ character followed by a unique capital letter, followed by \. The following table lists the delimiter characters and their equivalent escape sequences:
|Hexadecimal character xx
In the \Xxx\ escape sequence, xx is a two-digit hexadecimal number representing the ASCII value of a character.
Note that the \ escape character has its own escape sequence.
In addition to the above escape sequences, some additional special escape sequences are defined. These escape sequences are left unchanged.
|Formatting Sequences (starting with a period)
|Character Set Codes
These escape sequences enable you to include formatting information as part of a segment composite.