Introduction
The Interchange Control Header (ISA) segment is a critical component of the EDI X12 standard, serving as the envelope that initiates and identifies an interchange of one or more functional groups and interchange-related control segments. Accurate configuration of the ISA segment ensures seamless communication between trading partners and compliance with industry standards.
ISA Segment Overview
The ISA segment is a fixed-length record consisting of 16 data elements, each with specific formatting requirements. Below is a detailed breakdown of each element:
| Element | Size | Name | Description | Notes |
|---|---|---|---|---|
| ISA01 | 2 | Authorization Information Qualifier | 00 | Indicates no authorization information present. |
| ISA02 | 10 | Authorization Information | Ten spaces | Blank if ISA01 is ’00’. |
| ISA03 | 2 | Security Information Qualifier | 00 | Indicates no security information present. |
| ISA04 | 10 | Security Information | Ten spaces | Blank if ISA03 is ’00’. |
| ISA05 | 2 | Interchange ID Qualifier (Sender) | ZZ | Mutually defined; commonly used for custom identifiers. |
| ISA06 | 15 | Interchange Sender ID | Sender’s unique ID | Left-justified and space-filled. |
| ISA07 | 2 | Interchange ID Qualifier (Receiver) | ZZ | Mutually defined; commonly used for custom identifiers. |
| ISA08 | 15 | Interchange Receiver ID | Receiver’s unique ID | Left-justified and space-filled. |
| ISA09 | 6 | Interchange Date | YYMMDD | Date of the interchange. |
| ISA10 | 4 | Interchange Time | HHMM | Time of the interchange. |
| ISA11 | 1 | Repetition Separator | ^ | Must be unique and not used elsewhere in the segment. |
| ISA12 | 5 | Interchange Control Version Number | 00501 | Indicates the version of the EDI standard. |
| ISA13 | 9 | Interchange Control Number | Unique number | Must match the control number in the IEA segment. |
| ISA14 | 1 | Acknowledgment Requested | 0 or 1 | ‘1’ indicates acknowledgment requested. |
| ISA15 | 1 | Usage Indicator | P or T | ‘P’ for production data; ‘T’ for test data. |
| ISA16 | 1 | Component Element Separator | : | Must be unique and not used elsewhere in the segment. |
Best Practices for ISA Segment Configuration
- Unique Identifiers: Ensure that both the sender and receiver IDs (ISA06 and ISA08) are unique and agreed upon by trading partners.
- Control Numbers: Maintain sequential control numbers in ISA13 to track interchanges effectively.
- Delimiters: Choose delimiters (ISA11 and ISA16) that do not conflict with data content.
- Testing: Use ‘T’ in ISA15 during testing phases and switch to ‘P’ for production environments.