ISO/IEC 29642:2009规定了容量为8.55 GB和17.1 GB的120 mm可重写光盘的机械、物理和光学特性。它规定了记录和未记录信号的质量、数据的格式和记录方法，从而允许通过这种盘进行信息交换。使用相变方法可以多次写入、读取和重写数据。这些磁盘被标识为+RW DL。 ISO/IEC 29642:2009还规定了容量为2.66 GB和5.32 GB的80 mm磁盘。这些圆盘具有与120 mm圆盘相同的特性，除了一些与较小尺寸相关的参数。附录中规定了80 mm椎间盘特有的所有参数。 ISO/IEC 29642:2009规定了以下内容:该磁盘的两种相关但不同类型； 符合性的条件； 测试、操作和存储磁盘的环境； 盘的机械、物理和尺寸特性，以便在数据处理系统之间提供机械互换； 盘上信息的格式，包括磁道和扇区的物理配置、纠错码和编码方法； 记录在磁盘上的信号的特性，从而使数据处理系统能够从磁盘上读取数据。 ISO/IEC 29642:2009规定了光盘驱动器之间的磁盘互换。与卷和文件结构的标准一起，它提供了数据处理系统之间的完全数据交换。

ISO/IEC 29642:2009 specifies the mechanical, physical and optical characteristics of 120 mm rewritable optical disks with capacities of 8,55 Gbytes and 17,1 Gbytes. It specifies the quality of the recorded and unrecorded signals, the format of the data and the recording method, thereby allowing for information interchange by means of such disks. The data can be written, read and overwritten many times using the phase change method. These disks are identified as +RW DL. ISO/IEC 29642:2009 also specifies 80 mm disks with capacities of 2,66 Gbytes and 5,32 Gbytes. These disks have the same characteristics as the 120 mm disks, except for some parameters related to the smaller dimensions. All parameters unique for the 80 mm disks are specified in an annex. ISO/IEC 29642:2009 specifies the following:

• two related but different types of this disk;
• the conditions for conformance;
• the environments in which the disk is to be tested, operated and stored;
• the mechanical, physical and dimensional characteristics of the disk, so as to provide mechanical interchange between data processing systems;
• the format of the information on the disk, including the physical disposition of the tracks and sectors, the error correcting codes and the coding method;
• the characteristics of the signals recorded on the disk, thus enabling data processing systems to read the data from the disk.

ISO/IEC 29642:2009 provides for the interchange of disks between optical disk drives. Together with a standard for volume and file structure, it provides for full data interchange between data processing systems.