Temperature—Choose a suitable temperature
and time for the compression set, depending upon the
conditions of the expected service. In comparative tests, use
identical temperature and test periods. It is suggested that the
test temperature be chosen from those listed in Practice
D 1349. Suggested test periods are 22 h and 70 h. The test
specimen shall be at room temperature when inserted in the
compression device. Place the assembled compression device
in the oven within 2 h after completion of the assembly and
allow it to remain there for the required test period in dry air at
the test temperature selected. At the end of the test period, take
the device from the oven and remove the test specimen
immediately and allow them to cool.