Example Segment: N1


N1 is the most commonly used segment in the referenced transaction sets. N1 is used to identify a party by type of organization, name, and code.  The bold N1 in the upper-left corner of the segment table is the name of the segment. This is the label referred to in the SEG. ID column of the Transaction Set Table.

Next to segment identification is the name of the segment and a brief description.

Underneath is a line that says Transaction Sets Used In. This table lists all the transaction sets that can use that particular segment. For N1, this is most of the defined EDI transaction sets.

The REF column is used by the ANSI X12 committee and can usually be ignored when developing an EDI system.

The ELE ID (Element Identification) column lists the identifier for each data element that makes up the segment. To look up details for a particular data element, turn to the Data Element Dictionary tab of your ANSI X12 documentation and look up the element with that number.

The Name column is the name of the data element.

Attributes

The attributes for the data element are listed in a table.

In the first column, M means Mandatory, O means Optional, and X means Conditional. When two elements are conditional, they are related to each other. You use either one or another, but never both. Refer to the Syntax Notes to determine the condition and which element to use depending on the various conditions. In older documentation, instead of the letter X, they use a C to stand for Conditional.

Next column tells what kind of data that goes into that particular element.

The last column is the minimum and maximum number of characters. So if you see 2/20, it says the minimum number of characters for the data element is 2 and the maximum number is 20.