This part of ISO 19973 provides test procedures for determining reliability of pneumatic cylinders with piston rod by testing and the methods of reporting the results of testing. The general test conditions and the calculation method provided in Part 1 of ISO 19973 apply to the first failure without repairs, but exclude outliers. The lifetime of pneumatic cylinders is usually given in number of cycles or in kilometres. Therefore, whenever the term “time” is used in this part of ISO 19973, this variable is to be understood as cycles or kilometres. This part of ISO 19973 also specifies test equipment and threshold levels for tests to determine the reliability of pneumatic cylinders with piston rods, both single-acting and double-acting. This part of ISO 19973 is intended to be applied to pneumatic piston rod cylinders that conform to ISO 6430, ISO 6432, ISO 15552 and ISO 21287; however, pneumatic piston rod cylinders that do not conform to these International Standards but are used in the same range of operating conditions can be tested in accordance with one of the classes defined in Tables 1 and 2 of this part of ISO 19973. It is necessary that any deviation from this part of ISO 19973 be documented in the test report.