All DICOM files and all data that comprise the ISO 9660 file system of the DICOM CD-R disc shall be stored either:
within Mode 1 sectors, or
within Mode 2, Form 1 sectors with CD-ROM-XA File Number = 0, Channel Number = 0 and Coding Information Byte = 0.
Notes: 1.The physical storage capacity of a CD-R disc can be 74 minutes (630 MB) or 80 minutes (700 MB) when using the Mode 1 or Mode 2 Form 1 format. The capacity is fixed by the pregrooved spiral track present on a blank CD-R. Some older CD players will not be able to read the 80 min capacity CD-R discs.
2. The DICOM standard prohibits the use of Mode 2 Form 2 sectors. This format is used to record data on CD-Rs that exceed 74 minute capacity and can also be used for smaller capacity CD-Rs. CD-ROM-XA Mode 2 Form 2 sectors do not have sector level error correction. This significantly decreases the reliability of the media and significantly increases the likelihood of data corruption.