This standard establishes the format of information on 19-mm type ID-1 instrumentation digital cassettes. It specifies the dimensions and locations of the helical data, control, time code, and annotation tracks. It defines the format and recoding requirements of the data block s forming the helical data record containing digital instrumentation and other associated data, and specifies the content, format, and recording method for the control record. This standard also specifies the recording requirements for longitudinal records contained in the annotation and the time-code tracks. The annotation and time-code record formats are not defined. The physical requirements, magnetic requirements, and test methods for the magnetic tape and tape cassette are not specified in this standard, but can be found in the references or in the technical literature. No licenses for patented or copyrighted features are required to implement compliance with this standard. All dimensions given are metric.