837 EDI Structure – ISA (Interchange Control Header)
837 EDI general envelope structure is described in the previous post. Below find the exact description of the Interchange Control Header (ISA). It is depicted a structural part of an envelope.
This is the beginning segment of almost all 837 EDI documents. This is the outermost envelope. All of the 837 EDI data is placed within this layer. The purpose of this segment is to identify the sender and receiver. Also it identifies date, time and control number information. This segment of 837 EDI transaction must match the IEA trailer segment.
ISA*00* *00* *12*8586755250 *01*807685339 *120101*0742*^*00501*000001899*0*P*>
ISA-01 through ISA-04: In the example above, ISA-01 through ISA-04 are not being used. These elements are hardly ever being used anymore. That is why they are 00 and null. They served authorization and security password purposes in the past.
ISA-05 and ISA-06: These segments represent the sender qualifier and the sender ID. In the example above ISA-05 has a qualifier of 12. This qualifier means the phone number. ISA-06 has the actual phone number.
ISA-07 and ISA-08: These segments represent the receiver qualifier and the receiver ID. In the example above ISA-07 has a qualifier of 01. This qualifier means the duns number and ISA-08 has the duns number.
ISA-09 and ISA-10: ISA-09 is the interchange date in YYMMDD format. ISA-10 is the time in HHMM format. This transmission was sent on January, 1st 2012 at 07:42
ISA-11: For 837 EDI Versions (see ISA-12) 00402 and greater this will serve as a repetition separator. It is used to separate repeated occurrences of a simple data element or a composite data structure. For example, a pipe character (I) or a carrot (“^”) (like in our example above) can be used in this field. For EDI versions 00401 or less this will always be a single character code value “U”. This code meaning – “U.S. EDI Community of ASC X12, TDCC, and UCS”.
ISA-12: This is the EDI standard published version number. In the example above it is 00501; 00501 Standards Approved for Publication by ASC X12 Procedures Review Board through October 2003.
ISA-13: This is a 9 digit control number used for tracking purposes. This number must match IEA-02 (Interchange Envelope Trailer). This number should be unique. The number should not be re-used for at least 3 years.
ISA-14: This is hardly ever used part. It should not be confused with the 997 acknowledgement document. This is the acknowledgement request indicator for the TA1 transaction. It used mainly for reporting the status of processing a received interchange header and trailer or the non-delivery by a network provider. Usually this will be set to ‘0’ value. However, some payers send these back as part of their acknowledgement process. The payers companion guide will indicate if the TA1 is being used or not.
ISA-15: This indicates whether data enclosed by this interchange envelope is test ‘T’, production ‘P’ or information ‘I’. In the example above it is ‘P’
ISA-16: This field provides the delimiter. It is used to separate component data elements within a composite data structure. The value must be different than the data element separator and the segment terminator. In the example above the value is the “colon” (:). However, it can also be any valid ASCII special character. This is also referred to as the Sub-Element Separator.